Class 7 Geography

WBBSE Chapter 10 Map Pointing

Question 1. On an outline map of Africa, point the following-

1. Atlantic Ocean
2. Indian Ocean,
3. Mediterranean Sea,
4. Red Sea,
5. Strait of Gibraltar,
6. The Equator,
7. Tropic of Cancer,
8. Tropic of Capricorn,
9. Prime Meridian,
10. Atlas Mountains,
11. Drakensberg Mountains,
12. Sahara Desert
13. Ahaggar and Tibesti Plateaus,
14. Nile Basin,
15. Mount Kilimanjaro,
16. Kalahari and Namib Desert

Answer:

Question 2. On an outline map of Africa, point the following-

1. River Niger,
2. River Nile,
3. Lake Victoria,
4. Blue Nile,
5. River Congo
6. Lake Chad,
7. Strait of Mozambique,
8. Lake Tanganyika,
9. Mt. Taubkal,
10. River Limpopo,
11. Madagascar Island,
12. Somali peninsula
13. Khartoum
14. Alexandria
15. Cairo

Read And Learn Also WBBSE Solutions For Class 7 Geography

Answer:

Understanding Map Skills

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

Chapter 10 Map Pointing At A Glance

 

 

 

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation Long Question And Answers

Question 1. Describe the geographical significance of Africa.
Answer:

Geographical significance of Africa:

The geographical significance of Africa are as follows-

1. Enormous size:

• With an area of 30.3 million sq km, Africa is the second largest continent by area and by population count.
• It almost covers 20% of the entire land area of the Earth.

2. Important latitudes and longitudes:

• The Equator passes halfway through Africa, whereas, the Tropic of Cancer passes through the northern part and the Tropic of Capricorn through the southern part of Africa. The Prime Meridian also passes through the western part of the continent.
• So, Africa is a unique continent with parts in the northern and southern hemispheres and also in the eastern and western hemispheres.

3. Landform:

This continent is mostly flanked by a plateau. Apart from this the northern part contains the enormous hot desert of the Sahara and the east of the continent is flanked by the Great African Rift Valley.

Read And Learn Also WBBSE Solutions For Class 7 Geography

4. Ancient plateau:

A major part of Africa is a part of the ancient Gondwanaland. Only the delta region observes the accumulation of the new alluvial soil.

5. Climate:

• As the Equator passes through the middle of Africa, the major portion of Africa receives the vertical rays of the Sun and experiences a hot summer climate throughout the year.
• The northern and southern parts of Africa remain under the influence of the Tropic of Cancer and the Tropic of Capricorn.
• So the northern and the southern part of Africa remain in the temperate zone and experience moderate climate.

6. Rivers:

The longest river of the world, the Nile, flows through this continent. Apart from this, several other voluminous rivers such as Congo, Niger, and Zambezi also flow through Africa.

7. Mineral resources:

• Africa leads in the production of diamonds in the entire world.
• Other than this, Africa deserves a special mention for the production of mineral resources like gold, coal, mineral oil, natural gas and others.

8. Historical significance:

• One of the earliest civilizations of the world evolved from the eastern part of Africa.
• Apart from this, one of the most important nations in the history of the world Egypt is also located here.

Understanding Africa’s Natural Vegetation

Question 2. Describe the physical features of Africa.
Answer:

Physical features of Africa:

Africa is mostly a vast eroded plateau region. Based on its variation in physical features, Africa can be delineated in the following divisions-

1. North-west mountainous region:

• The Atlas Range stretches over the northwestern part of Africa. It is a fold mountain with an extension of 2500 km.
• It comprises three parallel ranges. Mt. Taubkal (4165 m) is the highest point of the Atlas Range.

2. Desert plateau region:

The northern part of Africa that was originally a part of the ancient Gondwanaland is currently a worn-out low plateau.

• The east-west extension of the desert plateau is between the Atlantic Ocean in the west to the Nile River Basin in the east.
• Two important lakes of this region are the Volta and the Chad.
• The two great plateaus of this region are the Fouta Djallon and Adamawa.
• Ahaggar Plateau and the Tibesti Plateau of Chad require a special mention.

 

3. High plateau region:

The most noteworthy part of the eastern plateaus is marked by depressions, popularly known as the Great African Rift Valley.

• Stretching for more than 6,400 km from the Red Sea in the north to Mozambique in the south, this is the world’s longest rift valley region.
• Several lakes are found in this rift valley region that mark the source of water for the local inhabitants.
• Some important lakes of this region are Turkana, Albert, Edward, Nyasa, Tanganyika and Kivu.

4. Coastal plain region:

Coastal Africa has a few natural harbours. Along the coast lies a thin strip of coastal plain.

• This coastal plain rises to the plateau.
• Only the coastal plains near the Mediterranean Sea in the north and the Atlantic Ocean in the west are relatively broader.
• Apart from this, the delta region of Congo, Niger and Orange Rivers are also quite wide.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. Discuss the characteristic features of the rivers of Africa.
Answer:

Characteristic features of the rivers of Africa:

The characteristic features of the rivers of Africa are as follows-

1. Versatile usage:

The rivers are fast-flowing and are generally of perennial type and so, are useful for both irrigation and hydel power generation.

2. Fast-flowing and develops waterfalls:

As Africa is mostly a shield region, the rivers are generally fast-flowing. For instance, from Khartoum to the Aswan High Dam, the Nile witnesses 6 cataracts Victoria Waterfall is an example of such a waterfall that is formed on the River Zambezi.

3. Formation of large delta:

The mouths of the rivers Congo, Niger, and Orange witness large deltaic plains. Nile fans out into seven delta distributaries. The Nile Delta, the epitome of all deltas, comprises a gulf of the prehistoric Mediterranean Sea and is composed of silt, brought mainly from the Ethiopian Plateau.

4. Rivers are long but only small parts are navigable:

The rivers of Africa are long but most parts of them are not navigable. For instance, out of 6650 km of length, only 1500 km of the River Nile is navigable.

Question 4. Describe the reasons for the variation of climate in Africa.
Answer:

Reasons for variation of climate in Africa: The followings are the reasons for the variation of climate in Africa-

1. Latitudinal location:

• From north to south Africa extends from almost 38°N to 35°S and so, the Equator passes almost through the middle of Africa, diving it into two almost equal parts.
• So, Africa is a part of both hemispheres.
• When the sun’s rays fall vertically on the northern hemisphere and obliquely on the southern hemisphere, it is summer in the northern part of Africa and winter in the southern part of Africa and vice versa.

2. Distance from the sea:

• The length and breadth of Africa is spread over a vast expanse.
• For this reason, the regions that lie in the interior do not experience much influence of the sea, and deserts have developed in the northern and the central parts of the country.
• On the other hand, regions near the coast experience a much more equable type of climate.

3. Ocean current:

• The coasts of Africa that face the cold currents generally experience a cold dry climate.
• For instance, the north-western coast of Africa is influenced by the cold Canary Current and subsequently, the western part of the Sahara Desert has developed.
• Similarly, the Kalahari and Namib Deserts have developed because of the influence of the Benguela Current along the southwestern coast.
• Moreover, with the influence of the warm current of Guinea and Mozambique, Guinea and the East African coast receive heavy rainfall.

4. Altitude:

• The temperature always falls with the increasing altitude.
• This is why Mt. Kilimanjaro with a height of 5,895 m is snow-capped even if it is located in the equatorial region.

Question 5. Describe the characteristics of the various climatic zones of Africa.
Answer:

Characteristics of the various climatic zones of Africa:

The characteristics of the various climatic zones of Africa are as follows-

Question 6. Describe the variance in the natural vegetation due to variations in climate in Africa. Or, Mention the relationship between the climate and natural vegetation of Africa.
Answer:

Variance in the natural vegetation due to variation in climate in Africa: Variance in the natural vegetation is noticed due to variation in climate in Africa. They are as follows-

 

Question 7. Why is Egypt known as the ‘Gift of Nile’?
Answer:

Reasons why Egypt is known as the ‘Gift of Nile’:

The Nile flows through the Sahara Desert of northern Africa. The reasons why Egypt has been aptly called the ‘Gift of Nile’, by the Greek historian Herodotus, is discussed below-

1. Formation of floodplains:

• The average annual rainfall in Egypt is less than 25 cm. But as the source region of the Nile receives heavy rainfall, Egypt experiences floods.
• As a result, the arid regions of Egypt also get covered by silts, and agriculture becomes possible.

2. Agriculture:

• Agriculture in Egypt has become one of the main sources of livelihood.
• The major reason is the fertile silt, deposited by the Nile and the irrigation facility, that is available along the course of the river.
• As a result, high-quality cotton, wheat, banana, tobacco, millet, almond and such other crops grow here.

3. Animal rearing:

Large-scale grazing is done on the widespread grassland that stretches over the Nile Basin.

4. Transportation:

• The Nile is navigable and so, transportation facilities and trading become possible.
• The 1500 km stretch from Egypt to its mouth in the Mediterranean is navigable and this has helped trade through the waterways.

5. Generation of hydro-electricity:

The high dam on the course of the River Nile generates huge quantity of hydel power to meet the needs of industries and agriculture of Egypt.

6. Industrialisation:

The region sees the development of industries like textile, tobacco, processing of fruits, leather and such others.

Question 8. Briefly describe the geographical location of Africa.
Answer:

Geographical location of Africa:

Extending for 3,02,21,532 sq km of area, Africa is the second largest continent only after Asia

• This triangle-shaped continent is located to the south of Europe and southwest to Asia.
• Africa is bounded by the Red Sea and the Indian Ocean to its east, the Atlantic Ocean to the west, the Mediterranean Sea and the Strait of Gibraltar to the north and the confluence of the Indian Ocean and the Atlantic Ocean to the south.

 

Question 9. Write a short note on River Orange.
Answer:

River Orange:

• Orange (2,200 km) is one of the longest rivers in southern Africa and the fifth longest river of Africa. It rises from the Drakensberg Mountain and drains into Alexander Bay in the Atlantic Ocean.
• River Orange travels through the South African Velds.
• The Orange River Project and the Lesotho Highland Project have been planned to sustain the water demand for irrigation, urbanisation, and economic development in the central industrial areas of South Africa.
• A number of hydel power stations have been developed on this river. 29 reservoirs have been constructed on this river for irrigation.

 

Question 10. Write a short note on tropical grassland (Savanna).
Answer:

Tropical grassland:

The African Savanna is a tropical grassland. It covers Guinea, Sierra Leone, Liberia, Cote d’Ivoire, Ghana, Togo, Benin, Nigeria, Cameroon, Central African Republic, Chad, Sudan, Ethiopia, Somalia, the Democratic Republic of the Congo, Angola, Uganda, Rwanda, Burundi, Kenya, Tanzania, Malawi, Zambia, Zimbabwe, Mozambique, Botswana and the Republic of South Africa.

• Rainfall gradually decreases to the north and the south of the Equator. The summer season is longer and annual rainfall is around 150cm. Near the deserts, the annual rainfall decreases to about 25 cm.
• Grasses of a height of 4m-5m are found here. In between the widespread grassland trees like Baobab are noticed. The characteristics of the trees found here are-

1. The plants that are found in this region, develop thorns that are modified from the leaves, to prevent the excess transpiration.
2. They have a waxy coat on their stems.
3. These trees and plants have long roots, that develop to collect water from deeper underground.
4. Herbivorous animals like giraffes and carnivorous animals like leopards, lions, and hyenas are abundant in this region.
5. Due to low rainfall, the number of tall trees is less. Instead, extensive stretches of long grasses are found.

Question 11. Write a brief note or on the Mediterranean vegetation of Africa.
Answer:

Mediterranean vegetation of Africa:

• The coastal regions along the Mediterranean Sea and its southwestern part of Africa see coverage of the Mediterranean vegetation. The summers are rainless, rainfall is prevalent during winters.
• Annual rainfall is about 5 cm-100 cm. Cork, oak, birch, olive, walnut, fig, and other plants grow in this region. This region is popular for the variety of fruits that grow here. Trees like myrtle, oleander, lavender, and rosemary are also found in this region.

The characteristics of the trees found here are-

1. Woody, evergreen shrubs or small trees prevail in this region.
2. These trees have thick barks.
3. They generally have long roots.
4. Various fruit-bearing trees grow in this region.
5. The leaves of the trees are covered with a wax-like substance.

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation Short Question And Answers

Question 1. Africa was known as the ‘Dark Continent’ Why?
Answer:

The reasons why Africa was known as the ‘Dark Continent’ are discussed below-

1. The central part of Africa is covered with a dense forest, that is home to various fierce animals, poisonous snakes and insects.
2. A major portion of Africa faces a humid and unhealthy climate or a dry arid climate.
3. Several parts of Africa are still inaccessible because of lack of transportation facilities.
4. Many parts of Africa are the abodes of the Aboriginals. The development of human resources is not up to the desired level till date.
5. The economic and cultural development of Africa is still in a budding stage.

Question 2. Briefly describe the Atlas Mountain Range of Africa.
Answer:

The Atlas Mountain Range of Africa:

• Running from the south-west to the northeast in the north-western Africa, the Atlas Mountain Range (2000 km) forms the geologic backbone of Africa.
• This is a fold mountain that is fundamentally an isolated part of the European Alps.
• The Atlas Range is constituted of the Tell Atlas, the High Atlas, the Aures Mountains and the Saharan Atlas. Mt. Taubkal (4165 m) is the highest peak.

Question 3. Describe the desert plateau region of Africa.
Answer:

The desert plateau region of Africa:

• The northern part of Africa that was originally a part of the ancient Gondwanaland is currently a worn-out low plateau.
• This plateau gradually merges with the southern high plateau region and extends between the Atlantic Ocean in the west to the Nile River basin in the east.
• The world’s largest desert, the Sahara extends over the countries of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Tunisia and Sudan.
• The dry stony Hamada, shifting sand dunes-Aerg, and the oasis are all typical features of this desert plateau region. Two important lakes of this region are the Volta and the Chad.

Question 4. Write a brief account on the Great African Rift Valley.
Answer:

Great African Rift Valley:

• The most noteworthy part of East Africa is marked by the depressions of the plateaus, popularly known as the Great African Rift Valley.
• Stretching about 6000 km, from the Red Sea in the north to Mozambique in the south, this is the world’s longest rift valley region. Several lakes are found in this rift valley region that marks the source of water for the local inhabitants.
• A few of the most important lakes of this region are Turkana, Albert, Edward, Nyasa, Tanganyika and Kivu.

Question 5. Describe the high plateau region of Africa.
Answer:

High plateau region of Africa:

• Africa has high plateaus to its east and south. These rise approximately 1006m above sea level with a minimum rise of 610m.
• The entire country of the Republic of South Africa is a plateau, with higher elevation towards the northern border.
• South of the South African plateau, three parallel steps form the rim, each separated by a strip of level ground between them. The Great Karoo makes up the largest of these gaps between steps.
• The East African Plateau is higher than the South African Plateau. To the east, Mount Kilimanjaro stands tall, forming almost the unconquerable highest point of Africa.
• Another significant plateau region is the Ethiopian Highlands. This is Africa’s largest continuous plateau.

Question 6. Why is Africa said to be a ‘Plateau Continent’?
Answer:

• Africa is made up of raised highlands, leaving behind only a narrow strip of coastline. Africa is a part of the ancient eroded Gondwanaland. The Sahara Desert covers northern and central Africa.
• In the southern part of Sahara lies two great plateaus-Fouta Djallon and Adamawa.
• The higher region in south-east Africa is formed by the Ethiopian Highlands, a rugged mass of mountains forming the largest continuous area of its altitude in the whole continent.
• The abundance of highlands and plateaus across the continent earns Africa the nomenclature of the ‘Plateau Continent’.

Question 7. Why is the dense forest region of the Congo River Basin evergreen?
Answer:

The Congo River Basin extends up to 10° latitude on either side of the Equator. The reasons why the dense forest of this region remains evergreen are-

1. The Congo River Basin experiences verticle rays of the Sun and thus the temperature remains high throughout the year.
2. The volume of water of the Congo River Basin is high. It adds excessive humidity in the air, thus convectional rainfall occurs every evening.
3. Due to high temperatures and excessive rainfall, dense forests remain evergreen in this region.

Question 8. What is the reason for the formation of so many rivers and lakes in Africa?
Answer:

• The East African Rift is an active continental rift zone in eastern Africa that developed almost 22 million years ago. These rifts are the outcome of the actions of numerous normal faults.
• This region experiences heavy rainfall as it is influenced by both equatorial and monsoon climates. As a result, numerous lakes like Victoria, Turkana and Albert have formed as water accumulates in the depressed regions.
• Apart from this, the excess rainfall flows down the slope to form major rivers that originate from this region. A few of the important rivers that originate from this region are Congo, Zaire, Shebelle and Jubba.

Question 9. Describe the lakes of Africa.
Answer:

lakes of Africa:

There are many lakes in Africa. These lakes can be divided into three sub-groups. They are. as follows-

1. Freshwater lakes of the mountainous regions:

• Lake Tana, Abaya, Chamo, Shala, and Langano are some of the important lakes that are found in the Ethiopian Highlands.
• Victoria, the largest lake of Africa and the second largest freshwater lake of the world, is located towards the south near the Equator.

2. Freshwater lakes of the African Rift:

Large lakes are present in the East African Rift area. They are Lake Tanganyika, Kyoga, Kivu, Malawi, Albert, Edward and such others.

3. Saltwater lakes of the deserts:

Chad Lake lies to the south of the Sahara Desert. Apart from this, there are Chottor Shott. These are the saltwater lakes in the Atlas Mountain regions.

Question 10. Name the important cities on the course of the River Nile and the River Congo.
Answer:

The important cities on the course of the River Nile and the River Congo are listed below-

 

Question 11. Write a short note on River Congo.
Answer:

River Congo:

• Congo (formerly known as the Zaire River), the second longest river of Africa, rises in the northernmost part of Zambia and flows towards the west.
• The river originates from the wettest area of Africa.
• With a length of 4,700 km, the volume of discharge is more than the Nile. River Congo forms deep valleys in different places along its course and flows into the Atlantic Ocean.
• The entire course of the river mostly passes through the equatorial region. Along with its many tributaries, the Congo River forms the continent’s largest system of navigable waterways.
• Boyoma and Livingstone Falls have developed on the course of this river. The important cities developed on the course of this river are Kisangani, Kinshasa, Brazzaville, Bandaka, etc.

Question 12. Write a short note on River Niger.
Answer:

River Niger:

• Niger, the principal river of West Africa and the third-longest river (4180 km) of Africa, rises from Guinea Highlands.
• The river flows towards the Sahara Desert and is opposite to the Atlantic Ocean.
• The river flows northward up to Timbuktu then turns south and enters Nigeria. It forms a delta at its mouth which is highly populated.
• Cultivation and livestock rearing are major sources of livelihood here. Migratory birds flock the marshy lands of this delta every year.

Question 13. How do the latitudes influence the climate of Africa? Or, What would be the effect of latitude on the climate of Africa?
Answer:

The major portion of Africa comes under the influence of the hot torrid zone as the latitudinal extension of Africa ranges from almost 38°N to 35°S.

• As the Equator passes through the middle of Africa, the major portion of Africa receives the vertical rays of the Sun and experiences a hot summer climate throughout the year.
• The northern and southern parts of Africa remain under the influence of the Tropic of Cancer and the Tropic of Capricorn.
• So we see that the northern and southern part of Africa remain in the temperate zone and experience a moderate climate and the middle-most part of Africa remains in the torrid zone and experience hot and humid climate.

Question 14. What would be the effect of seas or oceans on the climate of coastal areas and the places away from the coasts?
Answer:

• The location of the Red Sea and the Indian Ocean to the east of Africa, the Atlantic Ocean of its west, the Mediterranean Sea to the north and the Indian Ocean to the south influences the coastal climate of Africa.
• The entire coastal region enjoys a maritime climate.
• On the other hand, the highland regions of Africa being away from the coastline experiences an extreme type of climate.

Question 15. How do ocean currents influence the climate of Africa? Or, What is the effect of ocean currents on the climate of the coastal region?
Answer:

Ocean currents influence the climate of a place, especially the coastal regions. This is also true in the case of Africa.

1. The coasts of Africa that experience the flow of cold ocean currents, experience a dry climate, resulting in the formation of deserts. For example, the Sahara Desert has formed as the cold Canary Current flows along the northwest coast of Africa.
2. Similarly, the Kalahari and the Namib Deserts have formed because the cold Benguela Current flows along the south- west coast of Africa.
3. On the other hand, under the influence of the warm Guinea Current and the Mozambique Current, heavy rainfall is received by the Guinea coast and the east coast of Africa respectively.

As a result of the unbroken coast, the ocean current is unable to influence the interiors of Africa.

Question 16. What is the reason for the variance in temperature across Africa?
Answer:

Following are the reasons for the variance in temperature across Africa-

1. Northern Africa experiences a hot summer season during the months of June and July. During this period the Sahara Desert region experiences temperatures of even upto 58°C.
2. At the same time, the southern part of Africa experiences winter. So, the temperature in the Drakensberg Mountain in the south-eastern stretches of Africa falls down to 4°C.
3. The months of December and January witness summer in the southern part and winter in the northern part of Africa.
4. Africa experiences both summer and winter twice, as the northern part of Africa is in the northern hemisphere and the southern part is in the southern hemisphere.

Question 17. What is the reason for the variance in rainfall patterns across Africa?
Answer:

Followings are the reasons for the variance in rainfall patterns across Africa-

1. The middle part of Africa lies under the equatorial region and so, experiences heavy convectional rainfall. The average annual rainfall is more than 150 cm.
2. As we move away to the north and the south from the equatorial region, the amount of rainfall decreases gradually. The desert regions of Sahara and Kalahari receive an average annual rainfall of 15 cm or less.
3. Few of the places here even do not receive rainfall at all for 2-3 consecutive years.
4. The eastern coast of Africa receives heavy monsoon rainfall during the summer seasons.

Conceptual Questions on Desertification in Africa

Question 18. Describe the characteristics of the regions in the equatorial climate.=
Answer:

The equatorial climate is prevalent up to 10° north and south of the Equator, under which the Congo River Basin and the coast of the Gulf of Guinea fall.

The characteristic of the regions in the equatorial climate are as follows:

1. Throughout the year, this region experiences high temperatures (average annual temperature is 27°C) and heavy convectional rainfall (average annual rainfall between 200 cm-250 cm).
2. There is heavy rainfall almost every afternoon so, it is known as the 4 o’clock rain.
3. Not much seasonal variation is observed in these regions.
4. All through the year, the weather remains hot and humid-which is very uncomfortable and quite unhealthy.

Question 19. Write a note on an equatorial evergreen forest of Africa.
Answer:

Equatorial evergreen forest of Africa:

• The equatorial evergreen forest of Africa stretches from the central Congo Basin and the coast of Guinea over the countries of the Republic of Congo, Cameroon, southern Nigeria, Cote d’Ivoire, Liberia, Togo, and eastern Madagascar.
• The high temperature of about 27°C and annual rainfall of about 200 cm-250 cm is prevalent in this region.
• Ebony, Mahogany, Palm, Camphor, and such other species of trees are found here.

The characteristics of the trees found here are-

1. The range of trees in the forests encompasses very tall trees to dense undergrowth.
2. Trees are evergreen in nature-the leaves are green throughout the year.
3. The forest sees stratified vegetation-
   1. The highest strata (30-45 m),
   2. The middle strata (13-30m) and
   3. The lower strata (0-15m).
4. The trees are broad-leaved and form a canopy.
5. The forest is almost impenetrable by sunlight.

Question 20. Describe the characteristics of the regions in the hot desert-type climate.
Answer:

The characteristics of the regions in the hot desert-type climate are as follows-

1. The desert regions of the Sahara in the north of Africa and Kalahari, and Namib in the south of Africa experience very dry and extreme type of climates.
2. Sand-covered or rocky landforms, cloudless sky, and dry climate of the desert region result in extremely hot days and extremely cold nights.
3. The annual range of temperature is also very high.
4. During summers the temperature goes up to almost 55°C.
5. These regions experience very less rainfall, sometimes even lower than 25cm. Sometimes the regions in the hot desert-type climate do not experience rainfall for 3 to 4 years.

Question 21. Write a short note on the desert vegetation of Africa.
Answer:

Desert vegetation of Africa:

• The northern and the south-western dry and arid regions come under the coverage of the desert vegetation of Africa. Rainfall is almost absent over here. Day temperatures are very high and night temperatures are very low.
• Small shrubs are generally sparsely located in this region. In several regions, smaller plants like Cactus, Acacia, thorny bushes and even taller trees like dates are found around oases.

Characteristics of the trees found here are-

1. Leaves on trees are very less because of the arid conditions.
2. These trees have long roots and thick stems.
3. These trees generally have fleshy and swollen stems, covered by modified thorns and hair.
4. The regions that have underground water storage see more assemblage of trees.
5. Oases can be observed in these regions.

Question 22. Write a brief note on the mountain vegetation of Africa.
Answer:

Mountain vegetation of Africa:

• The East African Highlands and the mountainous regions of South Africa witness an assemblage of softwood forests that come under the mountain vegetation of Africa.
• Pine, Fir, and such other trees are found here. This vegetation mostly comes under the coniferous type of forest and certain other portions of the forest come under the temperate deciduous type of forest.

The characteristics of the trees found here are-

1. Mostly coniferous trees grow here and in certain regions, grasslands are also found because of the presence of a cool climate.
2. The trees are mostly cone-shaped.
3. The vegetation comprises softwood trees.

Question 23. Discuss the reasons for the development of dense forests in the Congo River Basin.
Answer:

• The Congo River flows through the equatorial climatic region and so, receives vertical sun rays all through the year. As a result. all around the year, the river basin experiences only a hot humid summer season.
• The average temperature generally varies between 25°C – 27°C. Apart from this, these regions also receive daily afternoon rainfall that generally amounts to 200 cm-250 cm or more annually.
• This creates an ideal scenario for the growth of dense vegetation. So, an assemblage of dense, stratified evergreen. the forest is seen in the Congo River Basin.

Question 24. Briefly describe the monsoon deciduous forests of Africa.
Answer:

The monsoon deciduous forests of Africa:

In eastern Africa, the coasts of Mozambique, Tanzania, Kenya, and Somalia are covered by monsoon deciduous forests. The regions with less rainfall see an assemblage of Teak, Sal, Gamhar, Chaplas, Sandals,s and others. On the other hand, in the regions with more rainfall, trees like Rosewood, Mahogany, Ironwood, Neem, Bamboo, and Cane are found. The monsoon deciduous forests of Africa show the following characteristic-

1. The trees shed their leaves in the winter.
2. The wood from these trees is used for making furniture.
3. The forest is not very dense but relatively sparse.
4. Large coverage of forest sees similar types of trees.
5. The forest is easily penetrable as there is very less or no undergrowth.

Question 25. List the variance in the natural vegetation due to variations in climate in Africa.
Answer:

Due to variances in climate, an evident variation in the natural vegetation can be noticed everywhere, and Africa is not an exception.

Question 26. Describe the location of the important latitudes and longitudes of Africa.
Answer:

• The Equator passes halfway through Africa and the Prime Meridian passes through the western part of Africa.
• From west to east Africa extends from 17°33’W to 51°24’E longitude and from north to south it extends from 37°20’N to 34°52’S.
• Even the Tropic of Cancer and the Tropic of Capricorn both pass through Africa.

Question 27. Why has the rift valley formed in East Africa?

Answer:

• Due to tectonic movements, faults have formed on the surface in East Africa. The land between the two faults has subsided to form a rift valley.
• A number of lakes have been formed in the rift valley region. These lakes are large and deep.

Question 28. What are the physiographic divisions of Africa?
Answer:

Physiographic divisions of Africa:

Though the major portion of Africa comes under a residual plateau region, but still Africa can be divided into four physiographic divisions. They are as follows-

1. North-west mountainous region,
2. Desert plateau region,
3. High plateau region and
4. Coastal plain region.

Question 29. Write about the coastal plain region of Africa.
Answer:

Coastal plain region of Africa:

• Coastal Africa is very even with few natural harbors. Along the coast, there is a thin strip of coastal plain. This rapidly rises to the plateau.
• Only the coastal plains near the Mediterranean Sea in the north and the Atlantic Ocean in the west are relatively broader. Apart from this, the delta regions of Congo, Niger, and Orange Rivers are also quite wide.

Question 30. Describe the course of River Zambezi.
Answer:

The course of River Zambezi:

• Zambezi (2574 km) is the fourth longest river of Africa. The river originates in the Central African Plateau and flows eastwards into the Indian Ocean.
• On its course, it crosses the boundaries of six countries-Angola, Zambia, Namibia, Botswana, Zimbabwe Mozambique. Victoria and Chavuma are important falls that develop on the course of River Zambezi.
• Two major hydel power stations have also been built upon this river.

Real-Life Scenarios Involving Ecosystems in Africa

Question 31. What is 4 ‘o’clock rain?
Answer:

4 ‘o’clock rain:

• The Congo River Basin and the banks of the Gulf of Guinea near the Equator receives very heavy convectional rainfall. A main characteristic of this convectional rainfall is that, it occurs almost every day in the afternoon at around 4 o’clock.
• This is the reason why this rainfall is known as the 4 o’clock rain.

Question 32. Why is it winter in the south of Africa when it is summer in the north of Africa? Or, Why is the climate not similar at same time of the year in the northern and the southern part of Africa?
Answer:

• From north to south, Africa extends from almost 38°N to 35°S and so, the Equator passes almost through the middle of Africa, dividing it into two almost equal parts. So, Africa is a part of both hemispheres.
• When the sun rays fall vertically on the northern hemisphere and obliquely on the southern hemisphere, it is summer in the northern part of Africa and winter in the southern part of Africa and vice versa.

Question 33. Why is the peak of Mt. Kilimanjaro permanently snow-clad in spite of being situated in the equatorial region?
Answer:

• Though Africa is mostly part of the torrid zone, but the southeastern part of Africa falls under a cooler temperate climate, mostly because of the altitude.
• We know, that the normal lapse rate is 6.5°C. per 1000 m. So, Mount Kilimanjaro (5895 m) remains snow-capped all through the year.

Question 34. Why is the weather in central Africa different from the weather in the northern and southern parts at the same time?
Answer:

• The Equator passes halfway through Africa, whereas the Tropic of Cancer passes through the northern part and the Tropic of Capricorn through its southern part.
• Thus the central part of Africa experiences vertical sun rays and falls under the torrid zone. On the other hand, the northern and southern parts of Africa come under the temperate zones.

Question 35. Write about the influence of the ocean on the climate of Africa.
Answer:

The influence of the ocean on the climate of Africa:

• Africa is bounded by the Red Sea and the Indian Ocean to its east, the Atlantic Ocean to the west, the Mediterranean Sea and the Strait of Gibraltar to the north, and the confluence of the Indian Ocean and the Atlantic Ocean to the south.
• So, an equable climate is experienced in the coastal regions of Africa. However, the influence of the oceans gradually decreases to the interiors and thus extreme types of climate can be observed in interiors.

Question 36. Name the various climatic zones of Africa.
Answer:

Africa can be delineated into seven climatic zones based on the diversity in the weather conditions ranging from temperature, rainfall, air pressure and wind currents. They are-

1. Region of equatorial climate,
2. Region of savanna climate,
3. Region of monsoon climate,
4. Region of hot desert-type climate,
5. Region of temperate climate,
6. Region of Mediterranean climate and
7. The eastern coastal region of warm temperate climate

Question 37. Briefly describe the temperate grassland or Veld.
Answer:

The temperate grassland or Veld:

• The temperate grassland or Veld spreads over the plateau region of South Africa. Red Alfalfa are some of the most important species of grass, Ear grass, Meadow grass, Esparto, and of grasses.
• Trees like Poplar and Willow grow above the hill slopes. Plains are covered with small and rough grasses. The winter temperature of this region is low, the summers are moderate and the seasonal range of temperature is high.
• The amount of rainfall is more than the desert region.

Question 38. Write any three characteristics of the Veld.
Answer:

Three characteristics of the Veld:

The temperate grassland or Veld spreads over the plateau region of South Africa. The followings are some important characteristics of the Veld-

1. The climate of the Veld is rather variable. It experiences a high seasonal range of temperature due to its location away from the coast.
2. Most of the grasses (like Ear grass, Meadow grass, Esparto, and Alfalfa) here are small and rough. Thus, this region is used for animal gazing.

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation Very Short Question And Answers

Question 1. Name the second-largest continent of the world.
Answer: Africa.

Question 2. Which sea divides Africa from Asia?
Answer: Red Sea.

Question 3. Name the strait that separates Africa from Europe.
Answer: Strait of Gibraltar.

Question 4. What was Africa earlier called due to its inaccessibility?
Answer: Dark Continent.

Question 5. Name the sea situated to the north of Africa.
Answer: Mediterranean Sea.

Question 6. Name the gulf situated to the west of Africa.
Answer: Gulf of Guinea.

Question 7. Name the mountain range that runs across the northwest stretch of Africa.
Answer: Atlas Mountains.

Question 8. Which is the highest peak in High Atlas?
Answer: Mount Taubkal.

Question 9. Name the lake to the south of the Sahara Desert.
Answer: Chad Lake.

Question 10. Name the largest fault region in the world.
Answer: Great African Rift Valley.

Question 11. Name the highest peak in Africa.
Answer: Mount Kilimanjaro.

Question 12. What are the salt lakes, located between the Tell Atlas and the Saharan Atlas, known as?
Answer: Chott or, Shott.

Question 13. Name a significant island near Africa.
Answer: Madagascar.

Question 14. Name an important lake of the Great Rift Valley region.
Answer:  Lake Tanganyika.

Question 15. Name two deserts of South Africa.
Answer: Kalahari Desert and Namib Desert.

Question 16. Name the largest island in the continent of Africa.
Answer: Madagascar.

Question 17. What is the length of the longest river of Africa?
Answer: River Nile-6650 km.

Question 18. Name the largest city on the bank of the River Congo.
Answer: Kinshasa.

Question 19. Which peninsula connects Africa to Asia?
Answer: Sinai.

Question 20. Name an important river that flows through the southwestern part of the Sahara Desert.
Answer: River Niger.

Question 21. Name the dam that is constructed on the Zambezi River Basin between Zambia and Zimbabwe.
Answer: Kariba Dam.

Question 22. Name the second-longest river of Africa.
Answer: River Congo.

Question 23. Name the river that flows through the Veld grassland in Africa.
Answer: River Orange.

Question 24. Which is the largest freshwater lake in Africa?
Answer: Lake Victoria.

Question 25. Name the fifth-longest river of South Africa.
Answer: River Orange.

Question 26. Which river of Africa is known as the Oil River?
Answer: River Niger.

Question 27. Name two countries that are located on the bank of the Mediterranean Sea.
Answer: Libya and Algeria.

Question 28. Which part of Africa witnesses the low-lying landform covered with grassland interrupted by rift valleys and scattered lakes?
Answer: Eastern part of Africa.

Question 29. Which forest showcases stratified growth of trees along with baboon and chimpanzee-like animals?
Answer: Equatorial rainforest.

Question 30. Name the tropical grassland of Africa.
Answer: Savanna.

Question 31. Where in Africa can lions and zebra be seen?
Answer: Savanna Grassland

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation Fill In The Blanks

Question 1. Africa is the world’s _________ largest continent.
Answer: Second

Question 2. Suez Canal and the _________ divide Africa from Asia.
Answer: Red Sea

Question 3. _________ Canal divides Africa from Asia.
Answer: Suez

Question 4. Africa is bounded by _________ Ocean to its west.
Answer: Atlantic

Question 5. Africa is connected to Asia by the landbridge called _________ Peninsula.
Answer: Sinai

Question 6. The continent of Africa is _________shaped.
Answer: Triangle

Question 7. The Strait of _________ is located in northern Africa.
Answer: Gibraltar

Question 8. The highest peak of Atlas Mountain is _________.
Answer: Mt. Taubkal

Question 9. The Strait of _________ separates Africa from Europe.
Answer: Gibraltar

Question 10. _________ is the highest peak of Africa.
Answer: Mt. Kilimanjaro

Question 11. _________ mountain is a range across the northwestern stretch of Africa.
Answer: Atlas

Question 12. The hot desert located in the southern part of Africa is known as _________.
Answer: Kalahari

Question 13. _________ is the longest river of the world.
Answer: Nile

Question 14. Namib is a coastal desert in the _________ part of Africa.
Answer: Southern

Question 15. The second oldest freshwater lake of the world, _________ is located in the continent of Africa.
Answer: Tanganyika

Question 16. _________ is the main mountain range of the eastern part of Southern Africa.
Answer: Drakensberg

Question 17. The Ahaggar Mountains are located amidst of _________.
Answer: Sahara

Question 18. The port of Alexandria is a _________ port.
Answer: Sea

Question 19. The largest island in the continent of Africa is the _________.
Answer: Madagascar

Question 20. The _________ Waterfall is located on the course of River Zambezi.
Answer: Victoria

Question 21. River _________ of Africa forms a large delta at its mouth.
Answer: Nile

Question 22. River _________ is the main river of the western Africa.
Answer: Niger

Question 23. The Zambezi river has its mouth in the _________ Ocean.
Answer: Indian

Question 24. Cap _________ is located to the south of Madagascar.
Answer: St. Mary

Question 25. Cape Town of South Africa experiences _________ type of climate.
Answer: Mediterranean

Question 26. The _________ delta region of Nile experiences _________ climate.
Answer: Mediterranean

Question 27. The _________ River Basin of Africa experiences an equatorial type of climate.
Answer: Congo

Question 28. Sunlight hardly penetrates to the forest- floor of the _________.
Answer: Equatorial

Question 29. Alfalfa grass grows in the _________ grassland of South Africa.
Answer: Veld

Question 30. The regions with a Mediterranean type of climate experience rainfall in the _________ season.
Answer: Winter

Question 31. _________ trees grow in the continental desert region of Africa.
Answer: Date Palm

Question 32. Chlorophyll is found in the _________ leafless vegetation of the hot desert regions.
Answer: Stems

Question 33. Grapes: Mediterranean climate:: Cactus: _______.
Answer: Desert climate

Question 34. River Congo: West flowing:: _______: East flowing.
Answer: River Zambezi

Question 35. Tropical grassland: Savanna:: Temperate grassland: _______.
Answer: Veld

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation True Or False

Question 1. Mount Kilimanjaro is snow-capped even though it is situated in the equatorial region.
Answer: True

Question 2. The continent of Africa experiences both summer and winter twice a year.
Answer: True

Question 3. The middle portion of Africa comes under the influence of the sub-tropical high-pressure zone, whereas the northern and southern parts come under the influence of the equatorial low-pressure zone.
Answer: False

Question 4. The northeast trade winds blow over the northern parts of Africa.
Answer: True

Question 5. The temperate grassland of Veld is situated in central Africa.
Answer: False

Question 6. The Mediterranean Sea is located in the southern part of the continent of Africa.
Answer: False

Question 7. The temperature of the equatorial climatic region is very low.
Answer: False

Question 8. Monsoon climate can be observed in the northern parts of Africa.
Answer: False

Question 9. The trees of the Mediterranean forest have small and thick leaves with waxy cuticles.
Answer: True

Question 10. Congo is the only river in Africa that crosses the Equator twice during its course.
Answer: True

Question 11. The Strait of Gibraltar is located to the north-western part of Africa.
Answer: True

Question 12. The Persian Gulf separates Africa from Asia.
Answer: False

Question 13. The Drakensberg Mountain Range lies in the south of Africa.
Answer: True

Question 14. The baobab tree can be mostly seen in the Savanna grassland area.
Answer: True

Question 15. Most region of Africa falls under the torrid zone.
Answer: True

Question 16. The Atlas Mountain Range lies to the south of the Sahara Desert.
Answer: False

Question 17. The grassland to the north of Africa is known as the Veld.
Answer: False

Question 18. The hydel power project on Victoria Waterfall is located in Cameroon.
Answer: False

Question 19. One of the most important examples of a navigable river of Africa is River Orange.
Answer: False

Question 20. River Volga flows through the continent of Africa.
Answer: False

Question 21. Victoria Waterfall is formed on the course of River Orange.
Answer: False

WBBSE Chapter 10 Continent Of Africa Topic A Physiography Drainage And Natural Vegetation Match The Columns

1.

Answer: 1. G, 2. A, 3. C, 4. E, 5. D, 6. F, 7. B, 8. H

2.

Answer: 1. E, 2. C, 3. D, 4. B, 5. F, 6. A

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Long Question And Answers

Question 1. Write about the oil-producing countries of South-West Asia.
Answer:

Oil-producing countries of south-west Asia:

The oil-producing countries of South-West Asia are-

1. Saudi Arabia
2. Iran
3. Iraq
4. Kuwait
5. Oman
6. Qatar
7. United Arab Emirates
8. Syria, etc.

The discussion on the oilfields of these oil-producing countries is as follows-

Read And Learn Also WBBSE Solutions For Class 7 Geography

1. Saudi Arabia:

Saudi Arabia is the most important petroleum-producing country of South-West Asia. It has 26% of the world’s petroleum reserves. The oilfields of this country are-

1. Ghawar (largest oilfield in the world),
2. Abqaiq
3. Ain Dar
4. Dhahran
5. Safaniya
6. Manifa.

2. Iran: The noteworthy oilfields of Iran are-

1. Masjid-i-Sulaiman
2. Shahr (Naft-i-Shah)
3. Aghajari
4. Haft kol
5. Gachsaran
6. Lali

3. Iraq: The noteworthy oilfields of Iraq are-

1. Kirkuk
2. Mosul.

4. Kuwait: The oilfields of Kuwait are-

1. Burgan
2. Aaljara
3. Magwa-All Hamadi.

5. Qatar: The oilfields of this country are-

1. Jebel Dukhan
2. Id-al-Sharqi.

6. United Arab Emirates: The oilfields of this country are-

1. Murban
2. Amirshahi

 

 

7. Oman: The noteworthy oilfield of Oman is-

1. Natin.

8. Syria: The oilfields of Syria are-

1. Omar
2. Al-jab.

 

Question 2. Name the petroleum-producing countries of South-West Asia.
Answer:

The petroleum-producing countries of South-West Asia:

South-West Asia comprises of the world’s best petroleum-rich countries.

1. The main petroleum producing countries are-Saudi Arabia,
2. Iran,
3. Kuwait,
4. Qatar,
5. United Arab Emirates,
6. Oman,
7. Bahrain,
8. Iraq,
9. Syria, etc.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. Write a short note on OPEC. Or, What is OPEC?
Answer:

OPEC:

The full form of OPEC is ‘The organisation of the Petroleum Exporting Countries’. OPEC was founded by 5 petroleum-producing countries in 1960. Its headquarter is located in Vienna (the capital of Austria). At present, the organisation has 13 members.

They are-

1. Saudi Arabia
2. Kuwait
3. Iran
4. United Arab Emirates
5. The Republic of the Congo
6. Libya
7. Nigeria
8. Algeria
9. Angola
10. Iraq
11. Venezuela
12. Gabon and
13. Equatorial Guinea.

Its main objectives are-

1. To coordinate and unify petroleum policies among member countries,
2. To keep a regular, efficient and economic supply of petroleum to all-consuming nations,
3. To secure a fair return on capital to those investing in the industry,
4. To secure fair and stable prices for petroleum producers.

Question 4. Which regions are included in the petroleum production belt in Saudi Arabia?
Answer:

Regions are included in the petroleum production belt in Saudi Arabia:

The world’s second-largest petroleum-producing country is Saudi Arabia. The petroleum-producing regions in Saudi Arabia are located in the interior of the country and the continental shelf of its neighbouring Persian Gulf.

Out of these, the maximum production of petroleum comes from the eastern part i.e. the Hasa region. The onshore petroleum mining regions are-

1. Ghawar
2. Abqaiq
3. Ain Dar
4. Abu Hadriyah
5. Khursani yah
6. Dammam
7. Qatif
8. Dhahran, etc.

Among the offshore petroleum fields in the continental shelf region of the Persian Gulf,

1. Safaniya,
2. Abu Safah and
3. Manifa are worth mentioning.

Question 5. Name the oil mines of Iran.
Answer:

Oil mines of Iran:

According to the latest data, Iran ranks fourth in the world in petroleum production. Most of the petroleum mines in Iran are located in the southwestern part of the country i.e. in the region of Khuzestan.

The centres of oil production are-

1. Masjid-i-Sulaiman,
2. Aghajari,
3. Gachsaran,
4. Haft Kol,
5. Lali,
6. Ahvaz,
7. Naft Shahr (Naft-i-shah),
8. Maidan-i-Naftun, etc.

Oil is also mined in the Qom or Qum region in Southern Tehran.

Question 6. What are the petroleum-producing regions of the United Arab Emirates?
Answer:

The petroleum-producing regions of the United Arab Emirates:

The world’s seventh-largest petroleum-producing country is the United Arab Emirates. Among the states in United Arab Emirates, Abu Dhabi and Sharjah are famous for petroleum production.

The important producing regions here are-

1. Zakum,
2. Asab,
3. Murban,
4. Bu Hasa,
5. Huwaila,
6. Amirshahi.

Question 7. Write a short note on Ghawar.
Answer:

Ghawar:

Ghawar is located in the eastern part of Saudi Arabia, a little away from the coasts of the Persian Gulf. The region is very important as-

1. It is very rich in petroleum resources. The length of the petroleum field located here is more than 220 kilometres.
2. This is the world’s largest petroleum mining area. Petroleum reserves in Ghawar are equal to the total petroleum reserves in the entire United States of America.
3. The petroleum produced here is exported to different countries in Europe, North America and Asia.
4. An average of 50 lakh barrels of petroleum is produced here every day.

Question 8. Write a short note on Safaniya.
Answer:

Safaniya:

Safaniya, located in the eastern part of Saudi Arabia is at a distance of 265 km north of Dhahran (located on the coast of the Persian Gulf). Safaniya is an important petroleum mine as-

1. It is the largest offshore oil mine in the world.
2. It has a reserve of about 37 billion barrels of petroleum and 5360 billion cubic feet of natural gas.
3. The petroleum produced here is exported to different countries in Europe, North America and Asia.
4. An average of 12 lakh barrels of petroleum is produced here every day.

Question 9. Show the mountains radiating from the Armenian Knot.

Answers:

1. Pontic
2. Taurus
3. Elburz
4. Zagros

Question 10. Show the mountains radiating from the Pamir Knot.

Answers:

1. Hindu Kush
2. Suleiman
3. Tien Shan
4. Altyn Tagh
5. Kunlun
6. Karakoram
7. Himalayas

Question 11.

 

Down:

1. Highest mountain range in the world.
2. The Indus Valley Civilisation centred around this river.
3. Sorrow of China. 5. This plateau is known as the “Roof of the World”.

Across:

4. Largest lake in the world.
6. A junction of numerous mountain ranges.

Answers:

Down: 1. HIMALAYA, 2. INDUS, 3. HWANG HO, 5. PAMIR
Across: 4. CASPIAN SEA, 6. KNOT

Question 12.

 

Down:

2. This river along with the Euphrates was the cradle of Mesopotamian Civilisation.
4. Largest coniferous forest in the world.

Across:

1. Longest river in Asia.
3. The longest river in southwest Asia.
5. Yellow River.

Answers:

Down: 2. TIGRIS, 4. TAIGA
Across: 1. YANGTZE KIANG 3. EUPHRATES 5. HWANG HO

Question 13. The climate of southwest Asian countries is very hot and dry. But, huge metropolitan cities have developed here. Compose a paragraph on how it has been possible.
Answer:

The development of huge metropolitan cities is the countries of south-west Asia:

• The climate of southwest Asian countries is very hot and dry. Vegetation is almost non-existent. Only deserts exist. Agricultural activity is almost non-existent in this region.
• In such a hostile environment, human settlement was very negligible. Petroleum reserves were discovered here in the beginning of the last century.
• After the discovery of huge reserves of petroleum, there has been a drastic change in the economy in this region. There is a huge reserve of oil in Saudi Arabia, Iran, Iraq, Kuwait, UAE, etc.
• Saudi Arabia alone contains 15.7% of the world’s crude oil reserves. There is a low demand of oil in this region due to the low population. That is why most of the mineral oil is exported abroad.

For this reason, the countries of southwest Asia earn a lot of money from trade. So, people here live a very luxurious life. As a result, Huge cities have sprung up in the vicinity of the oilfields.

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Short Question And Answers

Question 1. What are the uses of petroleum?
Answer:

The various uses of petroleum in various sectors are-

1. Industry: Petroleum is used as fuel and lubricant in industries.
2. Transport: Petroleum by-products like diesel, petrol, and gasoline is used in all types of transport.
3. Agriculture: Petroleum is indispensable in operating tractors, harvesters, reapers, and pump machines.
4. Production of thermal electricity: Petroleum is used in the production of thermal electricity.
5. Petrochemical industry: The petrochemical industry uses various by-products of petroleum.
6. Household: Petroleum as a fuel is used in many household activities, such as cooking.

Question 2. Why is most of the oil produced in South-West Asia exported?
Answer:

Most of the oil produced in South-West Asia exported:

South-West Asia is not much densely populated. Thus, the demand for mineral oil in this region is not high. Thus, the maximum amount of the oil produced in this region is exported.

Question 3. Fill up the knowledge hive information on OPEC.

Answers:

1. OPEC was formed in September 1960.
2. At present OAPEC has 13 countries as its members.
3. These countries export about 77% of petroleum in the world.
4. The chief administrative centre of OPEC is situated in Vienna in Austria.
5. The organisation determines the price of petroleum in the world market.

Question 4. Which region is called the ‘Heart of Asia’ and why?
Answer:

The Central Highlands of Asia is called the ‘Heart of Asia’. The region is called so because of the following reasons-It constitutes 40% of the total area of Asia.

1. It extends from the Mediterranean Coast in the west to the coastal plains of the East China Sea in the east and from the Himalayas in the south to Yablonoi and Stanovoy Mountains in the north.
2. Most of the mountains and mountain ranges, and ancient plateaus of Asia originate from here.
3. Most of the chief rivers of Asia originate from this region.

Question 5. “Continent of Asia: Cradle of Civilisation”-Explain.
Answer:

• Asia is one of the diverse continents with respect to races, religions, castes, cultures and livelihoods. Riverine civilisations had developed in this continent about 3500-5000 years before the birth of Christ.
• These include Harappa, Mohenjodaro and the Indus Valley Civilisation. The Mesopotamian civilisation along the Tigris and Euphrates rivers is also notable. The Hwang Ho River Valley was the foundation of Chinese Civilisation.
• Thus the continent of Asia is called the ‘cradle of civilisation’ or the birthplace of civilisation.

Question 6. State the importance of the South- west Asian countries in petroleum production.
Answer:

The importance of the South- west Asian countries in petroleum production:

• South-West Asia is the world’s largest petroleum-rich region. These countries have great importance in the global trade.
• The eight countries of southwest Asia constitute about 60% of the world’s total petroleum reserve and produce about 30% of the world’s total petroleum. As these countries have very less populations, their internal demand is also less.
• The primary member countries of the petroleum export trade controlling organisations i.e. OPEC and OAPEC are the South-West Asian countries.

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Very Short Question And Answers

Question 1. Which is the second largest oil-producing country in the world?
Answer: Saudi Arabia.

Question 2. Give the abbreviation for the organization named ‘Organisation of the Petroleum Exporting Countries.
Answer: OPEC.

Question 3. What is the total number of members of OPEC at present?
Answer: 13.

Question 4. Where is the headquarter of OPEC situated?
Answer: Vienna, Austria.

Question 5. Which is the largest oilfield of Iraq?
Answer: Rumaila oilfield.

Question 6. Which is the world’s largest onshore oil mining region?
Answer: Ghawar.

Question 7. Which is the largest offshore oilfield in the world?
Answer: Safaniya oilfield.

Question 8. Which is the largest oil refinery in Iran?
Answer: Abadan Refinery.

Question 9. In which country of the middle east is the world’s largest oil refinery situated?
Answer: Kuwait.

Question 10. I am a large continental landmass formed by combining the landmasses of Europe and Asia. Who am I?
Answer: Eurasia

Question 11. I am a plateau located approximately in the middle of the continent of Asia. I am also known as ‘Roof of the World’. Who am I?
Answer: Pamir Plateau

Question 12. The Pontic, Taurus, Elburz, and Zagros Mountain Ranges have radiated from me. Who am I?
Answer: Armenian Knot

Question 13. I am a remnant of an ancient plateau lying across the Arabian Peninsula. Who am I?
Answer: Arabian Plateau

Question 14. I am the lowest place on Earth. I am also called the Salt Sea. Who am I?
Answer: Dead Sea

Question 15. Floods were frequent in China due to me. I am known as the ‘Sorrow of China’. Who am 1?
Answer: Hwang Ho River

Question 16. Heavy convectional rainfall occurs every afternoon in me. Which region am I?
Answer: Equatorial region

Question 17. I am the longest river in Asia and the third longest in the world. Who am I?
Answer: Yangtze Kiang

Question 18. I am the principal centre of the cotton textile industry in China. Who am I?
Answer: Shanghai

Question 20. My river basin has fertile soil and a large variety of crops are grown abundantly. I am the ‘Granary of China’. Who am I?
Answer: Middle Yangtze Basin

Question 21. I am known as the ‘Holland of China’. Who am I?
Answer: Yangtze Kiang River Delta

Question 22. I am the longest man-made canal in the world. I am situated in China. Who am I?
Answer: Grand Canal

Question 23. I am the capital of Japan. I am not only the largest city in Japan but also in the world in terms of population. Who am I?
Answer: Tokyo

Question 24. I have been selected as an ideal eco-friendly city by the Japanese Government. Who am I?
Answer: Yokohama

Question 25. I am the world’s largest onshore oil field, located on the Persian Gulf. Who am I?
Answer: Ghawar

Question 26. I am the world’s largest offshore oil field. Who am I?
Answer: Safaniya

Question 27. I was formed with 12 countries from South- west Asia. My role is to fix the price of petroleum and ascertain its supply in the world market. Who am I?
Answer: OPEC

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Find The Odd One Out

Question 1. Indus civilisation Egyptian civilisation: Sumerian civilisation: Chinese civilisation
Answer: Egyptian civilisation (not a civilisation of Asia)

Question 2. Indian Ocean: Pacific Ocean: Arctic Ocean: Atlantic Ocean
Answer: Atlantic Ocean (not an ocean that bounds Asia)

Question 3. Arabian Plateau: Brazilian Plateau: Deccan Plateau Indo-China Plateau
Answer: Brazilian Plateau (not a plateau of Asia)

Question 4. Yangtze Kiang Si Kiang: Hwang Ho : Amu Darya
Answer: Amu Darya (not a river of China).

Question 5. Mahogany: Rosewood: Olive: Rubber
Answer: Olive (not a free of the equatorial climatic region)

Question 6. Tokyo: Yokohoma: Chiba : Shanghai
Answer: Shanghai (not a city of Japan)

Question 7. India Saudi Arabia: Iran Iraq
Answer: India (not a country of South- west Asia)

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Correct The Following

Question 1. The largest forest in the world is the Selva forest.
Answer: Taiga

Question 2. Tibet is called the ‘Roof of the World’.
Answer: Pamir

Question 3. Lake Superior is the largest lake in the world.
Answer: Caspian Sea

Question 4. Pontic Mountain radiates from the Pamir Knot.
Answer: Armenian Knot

Question 5. Hwang Ho is the longest river in Asia.
Answer: Yangtze Kiang

Question 6. The climate of Singapore is of Mediterranean-type.
Answer: Equatorial

Question 7. Ichang province is called the ‘Granary of China.
Answer: Hunan

Question 8. Safaniya is the world’s largest oilfield.
Answer: Ghawar

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Fill In The Blanks

Question 1. The headquarter of OPEC is located in ________.
Answer: Vienna

Question 2. The world’s second-largest oil-producing country is ________.
Answer: Saudi Arabia

Question 3. The world’s largest oil-producing centre is at ________ in Saudi Arabia.
Answer: Ghawar

Question 4. Lali oilfield is located in ________.
Answer: Iran

Question 5. The world’s largest onshore oil mine is at ________.
Answer: Ghawar

Question 6. The world’s largest offshore oilfield is at ________.
Answer: Safaniya

Question 7. Most of the oil mines of south-west Asia are located on the banks of the ________.
Answer: Persian Gulf

Question 8. The capital of Iraq is ________.
Answer: Baghdad

Question 9. The capital of Iraq is situated on the banks of river ________.
Answer: Tigris

Question 10. The first oil-producing centre in Saudi Arabia is ________.
Answer: Dammam

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia True Or False

Question 1. The world’s largest oil mine is Ghawar.
Answer: True

Question 2. The largest country by area in southwest Asia is Saudi Arabia.
Answer: True

Question 3. The largest petroleum-producing field in Iran is at Abadan.
Answer: False

Question 4 Basrah is an important petroleum-producing region in Iraq.
Answer: True

Question 5. The most petroleum-rich country of South- west Asia is Kuwait.
Answer: False

Question 6. The Persian Gulf and its coastal areas are the world’s largest source of oil.
Answer: True

Question 7. Ghawar in Saudi Arabia is the world’s largest offshore oilfield.
Answer: False

Question 8. Bahregan is an important oilfield in Iran.
Answer: True

Question 9. Abu Safah is an important offshore oilfield in Saudi Arabia.
Answer: True

Question 10. Al Ahmadi is the largest oil field in Iraq.
Answer: False

Question 11. 30% of the world’s total petroleum production comes from southwest Asia.
Answer: True

Question 12. OPEC control’s the price of petroleum in the of river world market.
Answer: True

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Scrambled Words

1. HOANGHW
2. UNKUNL
3. AISHGHAN
4. MAHAYOKO
5. YASANIFA
6. UIKOKSH
7. BIGO
8. DAARYAMU
9. ATAIG

Answers:

1. HWANG HO
2. KUNLUN
3. SHANGHAI
4. YOKOHAMA
5. SAFANIYA
6. SHIKOKU
7. GOBI
8. AMU DARYA
9. TAIGA

WBBSE Chapter 9 Continent Of Asia Topic D Oil Field Of South West Asia Match The Columns

Question 1.

Answer: 1. D, 2. E, 3. A, 4. C, 5. F, 6. B

WBBSE Chapter 9 Map Pointing

 

Question 1. On an outline map of Asia locate the following-

1. Caspian Sea
2. Yangtze Kiang Basin
3. Oil-belt of South-West Asia
4. Tropical deciduous forest
5. Pamir Knot
6. Tundra climatic region
7. Honshu
8. Dasht-e-Lut
9. Hindu Kush Range
10. Arabian Plateau
11. Ob River
12. Lake Baikal
13. Tokyo city
14. Gulf of Martaban
15. Bering Strait
16. Black Sea

Answer:

 

 

 

Question 2. On an outline map of Asia locate the following

1. Aral Sea
2. Coastal plains of India
3. Armenian Knot
4. Tokyo-Yokohama Industrial region
5. Manchurian climatic region
6. Saudi Arabia
7. River Tigris
8. Equatorial evergreen forest and Equatorial climatic region
9. Ural mountains
10. Islands of Japan

Answer:

 

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan Long Question And Answers

Question 1. What are the reasons for the growth of the Tokyo-Yokohama or Keihin industrial region?
Answer:

The reasons for the growth of the Tokyo-Yokohama or Keihin industrial region:

The Tokyo-Yokohama industrial region is situated on the eastern Pacific coast of Honshu, the largest island of Japan. The main reasons for the growth of this largest and most important industrial region of Japan are as follows-

1. Physical features:

The Tokyo-Yokohama region has developed on the wide Kanto Plain of Japan. So there are great facilities for the establishment of industries and transport.

2. Ports:

Both Tokyo and Yokohama are large ports. Since Yokohama is the largest port in Japan it is quite convenient to import raw materials like iron ore and cotton from foreign countries and to export finished products.

Read And Learn Also WBBSE Solutions For Class 7 Geography

3. Abundance of minerals:

Though there is a scarcity of coal, this region is an important centre of hydropower and nuclear power production. So there is an abundant supply of power.

4. Chief administrative centre:

Since Tokyo, the capital of Japan is centrally situated in this industrial region, administrative and governmental facilities are also easily available.

5. Skilled labour:

The density of the population is quite high and all labourers are highly skilled.

6. Developed transport and communication:

Tokyo and Yokohama are important international airports and seaports. Moreover, there is a dense network of railways and roadways. All these contribute to the industrialisation process.

 

Question 2. What are the problems faced by an industrial region?
Answer:

Problems faced by an industrial region:

• The problems faced by an industrial region are-
• Scarcity of land: Scarcity of land increases with the increase in industrial development. The availability of land for the establishment of new factories is a huge problem.
• High population density: High population density increases several problems in the industrial regions.
• Transport problem: High population density and scarcity of land pose a hindrance to the development of transport networks. A less developed transport network poses a problem to the export and import of goods and to from the region.
• Pollution: Industrial development increases the problem of industrial pollution.
•  High labour cost: Cheap labour is no longer available in an industrial region. Labour becomes expensive with an increase in demand.
• High import cost: If the industrial regions lack mineral deposits, then exporting them from elsewhere becomes expensive.
• Financial problems: The problem of approval of bank loans, and ill-developed trade and commerce also pose a hindrance to industrial development.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. How can the problems of an industrial region be solved?
Answer:

Necessary steps to solve the problems of an industrial region:

First, we have to determine the problem faced in the industrial region. Then, we have to take the necessary steps to solve the problem. They are-

• Import raw materials: If there is a lack of raw materials, then we have to make provisions for importing raw materials from other places at a feasible price or find some alternate raw materials.
• Provide training: If the productivity of workers is low, then proper training should be provided to them.
• Improve transport: In case of inconvenience in transport, new roads must be constructed. If necessary, new modes of transport should also be introduced.
• Sufficient capital: In case of lack of capital, arrangement of sufficient capital must be done from various government and non-governmental organisations.
•  Arrangement of land: For establishing new industries or for the expansion of old industries, land is required. In that case, the required amount of land must be arranged for at low prices.

Question 4. How did industries develop in Japan, in spite of deficiency in raw materials (iron ore and coal for the iron and steel industry, and raw cotton for the textile industry)?
Answer:

The reasons for the development of industries in Japan in spite of the deficiency in raw materials are as follows-

1. Unimaginable development in technology.
2. Easy availability of hydroelectricity.
3. Presence of nuclear energy as an alternative source of energy.
4. The convenience of transport.
5. High demand in the internal market.
6. Skilled labour.
7. The abundance of capital.
8. The abundance of raw materials in its neighbouring countries. All these favourable conditions combinedly helped the industrial development in Japan.

Question 5. What are the reasons for the development of the Tokyo-Yokohama industrial region?
Answer:

The reasons for the development of the Tokyo-Yokohama industrial region:

Tokyo-Yokohama industrial region is located in the eastern coast of Honshu Island, on the coastal plains of Tokyo Bay. This is the largest industrial region in Japan. The reasons for the development of this region are-

1. Presence of extensive plain land in the Kanto province of Japan (which is primarily a mountainous country). The Kanto Plain consists of 40% of the total area in Japan.
2. Japan being a country with advanced production of nuclear resources.
3. The transport and communication system within the industrial region is well developed.
4. Accessibility to two of the largest seaports-Tokyo and Yokohama.
5. Availability of cheap and skilled labour.
6. Presence of local water resources and hydroelectricity.
7. Tokyo is the capital of the country and the main administrative centre.

Question 6. What are the chief industries of Tokyo- Yokohama industrial region?
Answer:

The chief industries that have developed in the Tokyo-Yokohama industrial region are

1. Iron and steel industry,
2. Shipbuilding industry,
3. The cotton textile industry,
4. Electrical machines and electronics industry,
5. The woollen textile industry,
6. Silk textile industry,
7. Chemical industry,
8. Automobile industry,
9. The paper industry, etc.

Question 7. Write a short note on problems faced by the Tokyo industrial region and its solutions.
Answer:

Problems faced by the Tokyo industrial region and its solutions:

Tokyo industrial region is the most important industrial region in Japan. At present, this region is facing a few problems. They are-

1. High population density,
2. Very dense settlement resulting in lack of vacant land area,
3. The transportation system is bound within a limited area and,
4. High environmental pollution due to the presence of industries.
5. In the absence of reserves of high-quality coal and coke in Japan, the country has to import these for industrial purposes, making the process of manufacturing expensive.
6. The production process has become expensive with the increase in wages of labourers. To eradicate these problems, the Government of Japan has shifted the heavy industries from this industrial region of Tokyo to other prefectures like Chiba and Ibaraki.

Question 8. Why has Yokohama been selected as an “environmentally friendly model city”?
Answer:

Yokohama been selected as an “environmentally friendly model city”:

In the year 2008, Japan government selected Yokohama as an ‘environmentally friendly model city’. The reasons for this are-

1. The prevention measures for controlling industrial pollution have been successfully made effective in this region.
2. Management and recycling of waste materials in this industrial region is properly done.
3. Equal importance is given to agriculture besides industry in this region and,
4. special emphasis is given on the reclamation of fallow land and the rearrangement of the same.

Question 9. What are the causes behind the emergence of the Kihin or Tokyo- Yokohama Industrial Region as one of the best and most significant industrial regions of the world?
Answer:

The causes behind the emergence of the Kihin or Tokyo:

The reasons for the Tokyo-Yokohama Industrial Region being mentioned worthy compared to the other industrial regions of the world are-

1. Several steps have been taken to mitigate the problem of industrial pollution in this industrial region.
2. Importance has been given to the reclamation and reorientation of barren land to solve the problem of land scarcity.
3. Agriculture has been given equal and parallel importance as industries in the village areas. Thus, agriculture and industries both have equally developed.
4. Importance has been given to proper treatment and reuse of wastes.
5. The city of Yokohama has been declared as an ideal eco-friendly city by the government of Japan in the year 2008. [6] This city has been a worldwide trendsetter regarding urban planning.

Question 10. Write a short note on Tokyo.
Answer:

Tokyo:

• Tokyo, located in the Kanto Plain is the capital of Japan. It is the largest metropolitan city in Japan and also in the world, in terms of population. The population of Tokyo at present is about 1.4 crores (2021).
• In this metropolitan city, various industries like iron and steel, chemicals, machines, food products, etc. have developed. Tokyo is one of the most important industrial and commercial centres.

Conceptual Questions on Urbanization and Industry in Tokyo-Yokohama

Question 11. Write a short note on the city of Yokohama.
Answer:

City of Yokohama:

• Located on the eastern coast of Honshu Island along Tokyo Bay, about 20km south of Tokyo is Japan’s second-largest city, Yokohama. At present the population of Yokohama is about 3.7 million (2021).
• As the depth of sea is comparatively less near the port of Tokyo, Yokohama functions as the largest seaport of Japan. This city also has great importance as an industrial and commercial centre.
• Some of the important industries in this city are iron and steel industry, shipbuilding industry, electrical goods and electronics industry, food processing industry, etc.

Question 12. What is the importance of Tokyo-Yokohama Industrial Region in the industrial sector of Japan?
Answer:

Importance of Tokyo-Yokohama Industrial Region in the industrial sector of Japan:

The best and the largest industrial region which has developed around the cities of Tokyo and Yokohama in the Kanto Plain of Japan is known as the Tokyo-Yokohama Industrial Region.

It has tremendous importance in the industrial sector of Japan. The various reasons of its importance are as follows:

1. At present it is the largest industrial region in Japan. About 25% of the total industrial production in Japan is from here.
2. The main industries of this region are iron and steel, ship-building, engineering instruments, oil refinery, chemical products, silk, fur and cotton textile, electronic products, paper, food processing, biotechnology, etc.
3. Since the cities of Tokyo and Yokohama are located on the Gulf of Tokyo, advanced sea ports have developed on both.
4. Tokyo is the largest city of Japan and an educational and cultural hub. Yokohama is the second-largest city of Japan. Thus, the importance of the industrial region centred around these cities is prime.

 

 

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan Short Question And Answer

Question 1. Name the regional divisions or prefectures of the Kanto Plain.
Answer:

Seven regional divisions or prefectures are included in the Kanto Plain.

They are-

1. Gouma,
2. Tochigi,
3. Ibaraki,
4. Saitama,
5. Chiba,
6. Tokyo,
7. Kanagawa.

Question 2. Name the industrial centres of the Tokyo- Yokohama Industrial Region.
Answer:

The industrial centres of the Tokyo- Yokohama Industrial Region are-

1. Tokyo,
2. Yokohama,
3. Kawasaki and
4. Chiba.

Question 3. Name the important industries of the Tokyo-Yokohama Industrial Region.
Answer:

The important industries of the Tokyo- Yokohama Industrial Region are

1. Cotton textile,
2. Wool,
3. Paper,
4. Food processing,
5. Biotechnology,
6. Iron steel, electronics,
7. Automobile,
8. Aviation,
9. Information
10. Technology.

Question 4. Mention two problems of the city of Tokyo.
Answer:

The current problems of the city of Tokyo are-

1. Scarcity of land due to overpopulation,
2. The problem of environmental pollution is due to ever-increasing industrial pollution.

Question 5. Write two special features of the Yokohama Industrial Region.
Answer:

Two special features of the Yokohama Industrial Region are-

1. This city has been declared as an eco-friendly city by the Japanese Govt. (2008).
2. Agriculture has been considered to be as important as industries.

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan Very Short Question And Answers

Question 1. Among the four main islands of Japan, which one is the largest?
Answer: Honshu Island.

Question 2. At which part of Honshu is the Kanto Plain situated?
Answer: Eastern part.

Question 3. Which is the largest industrial region in Japan?
Answer: Tokyo-Yokohama Industrial Region.

Question 4. Which is the largest metropolitan city in Japan as well as in the world?
Answer: Tokyo.

Question 5. In which year, did the Japan Govt. declare Yokohama as an ideal eco-friendly city?
Answer: 2008.

Question 6. Name one of the major silk-producing regions in Japan.
Answer: Kanto Plain.

Question 7. Why Yokohama plays the role of the largest external port of Japan?
Answer:

The large ships cannot enter the port of Tokyo, as the gulf is shallow there. So, Yokohama plays the role of the largest external port of Japan.

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan Fill In The Blanks

Question 1. The Tokyo-Yokohama Industrial Region is located on the __________ Island.
Answer: Honshu

Question 2. The main city in the Tokyo-Yokohama industrial region is __________.
Answer: Tokyo

Question 3. About ¾ rd of the total population of Japan lives in __________.
Answer: Kanto Plain region

Question 4. Chiba is an important __________ producing centre in Japan.
Answer: Iron and steel

Question 5. __________ is the world’s most populous city.
Answer: Tokyo

Question 6. Yokohama is located at about __________ km away from Tokyo.
Answer: 30

Question 7. __________ is the second largest city of Japan.
Answer: Yokohama

Question 8. The Yokohama Port of Japan acts as an __________ port.
Answer: External

Question 9. __________ prefecture is one of the important paper production centres of Japan.
Answer: Shizuoka

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan True Or False

Question 1. The principal port of the Tokyo-Yokohama Industrial Region is Osaka.
Answer: False

Question 2. Tokyo-Yokohama is the second largest industrial centre in Japan.
Answer: False

Question 3. Kanto Plain is one of the major silk-producing regions in Japan.
Answer: True

Question 4. Japan imports iron ore from India as raw material for its iron and steel industry.
Answer: True

Question 5. The Tokyo-Yokohama Industrial Region has developed to the west of Honshu Island.
Answer: False

Question 6. The aerospace industry was initiated in Japan with the establishment of the National Space Development Agency.
Answer: True

Question 7. The silk textile industry in Japan operates with the help of imported silk from Australia.
Answer: True

Question 8. The Kanto Plain in Japan covers an area of about 30% of the country’s total land.
Answer: True

Question 9. 70% of the total population of Japan is employed in the industrial sector.
Answer: False

Question 10. Yokohama is situated at a distance of about 30 km from Tokyo.
Answer: True

Question 11. The largest seaport in Japan is Tokyo.
Answer: False

Question 12. The Tokyo-Yokohama Industrial Region is also known as Keihin Industrial Region.
Answer: True

Question 13. The largest island of Japan is Honshu.
Answer: True

WBBSE Chapter 9 Continent Of Asia Topic C Tokyo Yokohama Industrial Region Of Japan Match The Columns

Question 1.

Answer: 1. C, 2. D, 3. E, 4. B, 5. A

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China Long Question And Answers

Question 1. Discuss the geographical environment of the Yangtze Kiang Basin.
Answer:

Geographical environment of the Yangtze Kiang Basin:

The Yangtze Kiang Basin can be divided into the following regions from its source to mouth-

Szechuan Basin:

• This basin extends from the source of the River Yangtze, Ichang and is surrounded by Szechuan Alps, Tibetan Plateau and Yunnan Plateau. In the Tertiary Age there was a lake here which got filled up and gave rise to this lowland.
• This part of the basin is also called the Red Basin due to the presence of red sandstone. The climate of this region is pleasant, it is densely populated and prospers in agriculture.

Read And Learn Also WBBSE Solutions For Class 7 Geography

Middle Yangtze Basin:

• This part of the basin extends from Ichang to Hunan. It consists of a large plain, innumerable lakes and low hills. As this region is composed of new alluvium it is highly suitable for agriculture and is known as the ‘Granary of China’.
• Hunan is also called the ‘Rice Bowl of China’ for its considerable production of paddy cultivation. Other crops produced are wheat, cotton, sugarcane, oilseeds etc.

Delta region:

• The Yangtze Kiang Delta region extends from Hunan to the China Sea. It is a plain area and intensive agriculture produces loads of crops here.
• The river forms a huge delta and divides itself into a number of distributaries before draining into the China Sea.
• Many places have been reclaimed from the sea and so this delta region is also called the ‘Holland of China’.
• The Grand Canal which is located here is the longest canal in the world.

Shanghai, the largest city and port of China, is located in this region. This city is known as the ‘Manchester of China’ due to advancement in the textile industry.

 

Question 2. List the reasons for economic development in the Yangtze Kiang Basin.
Answer:

Reasons for economic development in the Yangtze Kiang Basin:

On the basis of the economy, the most developed region in China is the Yangtze Kiang River Basin. The reasons for the development of this region are-

1. The favourable climate, fertile soil and developed irrigation system help in the production of all types of crops in this region. 75% of the country’s paddy production comes from this region, along with 50% production of the other crops. Thus, this region is known as the ‘Granary of China’. The use of modern means of technology and agricultural implements can be noticed here.
2. The Yangtze Kiang Basin is one of the most mineral-rich regions in China.
3. Different types of industries have grown in this region namely cotton textile, shipbuilding, iron and steel, silk textile, cement, paper, etc.
4. Along with the inland waterways rail and road transport is also very developed. Thus import and export of materials through this developed transport network has enhanced the economic development of the region.
5. As the Yangtze Kiang Valley is the most densely populated region in China, cheap labour and the market is easily available.
6. This region is one of the main tourist areas in China.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. What are the reasons for the development of agriculture in the Yangtze Klang Basin?
Answer:

The reasons for the development of agriculture in the Yangtze Klang Basin:

The Yangtze Kiang Basin is one of the most agriculturally developed regions in China. The reasons for the development of agriculture in this region are-

1. Plain land formed by the rivers.
2. Highly fertile soil
3. Favourable climate for cultivation
4. Availability of sufficient cheap and skilled labour
5. High demand of agricultural products
6. Government aids.

Apart from these, high yielding variety of seeds, excellent fertilisers, modern tools and equipment for cultivation, provisions for modern agricultural training, etc are the main reasons for the development of agriculture in the region. The Yangtze Kiang River basin is the most agriculturally rich region in China. Out of the total agricultural production of China, 70% of wheat and more than 50% of the other crops is produced in this region.

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China Short Question And Answers

Question 1. Describe the environmental conditions of the Szechuan Basin.
Answer:

The environmental conditions of the Szechuan Basin:

• The Szechuan Basin constitutes the upper course of the Yangtze River which passes through the Szechuan Province. It extends from the source of the Yangtze River to Ichang.
• It is mainly a lowland bound by different plateaus and mountains on all sides and has been. formed by the depositions brought down by the four tributaries of the Yangtze River.
• The rivers which flow over this basin are Yalung Jiang, Min Jiang, Tuo Jiang, Jialing Jiang, Jinsha Jiang, etc. The climate prevailing over this region is pleasant and due to the predominance of red soil in the region, it is also called Red Basin.
• This region prospers in agriculture and is densely populated.

Understanding Yangtze River Basin

Question 2. Which region is called ‘The Granary of China’ and why? Or, Why is the Hunan Province known as the ‘Rice Bowl of China’?
Answer:

The Granary of China:

• The Middle Yangtze Kiang Basin in general or the Hunan Province in particular, the most agriculturally rich region in China, is also the largest geographical region in China.
• Favourable topography, moderate temperature and rainfall, fertile soil, dense population and government aid help in the abundant production of different types of crops (wheat, paddy, sugarcane, cotton, pulses, tobacco, oilseeds, etc.) across the river basin.
• Out of the total crop productivity in China, 70% is of paddy and more than 50% is of wheat. Apart from these, a huge number of mulberry trees are grown for the breeding of silkworms.
• Thus, this agriculturally rich Central or Middle Yangtze Kiang Basin is also known as the ‘Granary of China’.

Question 3. Which region is called ‘The Holland of China’ and why?
Answer:

The Holland of China:

• The delta region of the Yangtze Kiang is called the ‘Holland of China’, because, like the northwestern part of Holland (now the Netherlands), the Yangtze Kiang delta region is also a low flat plain and there are a number of polders (tracts of lowlands reclaimed from the sea) in this region.
• A large number of canals have been dug out for convenience in irrigation and cheap means of water transport similar to that in Holland.
• Although the region is not rich in minerals like that of Holland, it is rich in agriculture and industry and is densely populated.

Question 4. What are the divisions of the Yangtze Kiang Basin?
Answer:

The divisions of the Yangtze Kiang Basin:

The Yangtze Kiang Basin in China is generally divided into three sub-regions.

They are-

1. The Sichuan Basin comprises the upper course of the Yangtze Kiang, under the Sichuan province.
2. The Middle Yangtze Basin forming the middle course of the river, from Ichang to Hunan and
3. From Hunan to the coast of the China Sea lies the deltaic region formed by the lower course of the Yangtze Kiang.

Question 5. Give an account of the climate and soil of the Sichuan Basin.
Answer:

The climate and soil of the Sichuan Basin:

• The climate of the Sichuan Basin is pleasant.
• The average temperature during summer is between 27°C-32°C and the average temperature during winter season ranges between 10°C -15°C.
• It rains more during the summer season (average rainfall ranges between 100 cm-150 cm). Snowfall occurs occasionally during winter.
• The colour of the soil in this region is red, so, this region is also known as Red Basin.

Question 6. Which region is called the Rice Bowl of China and why?
Answer:

Rice Bowl of China:

• The Central Basin of the Yangtze Kiang is very fertile and the topmost crop-producing region in China.
• Due to the prevalence of comparatively hot and wet climate in the Hunan province of the Central Yangtze Basin, large quantities of rice is produced and so the Human province is called the ‘Rice Bowl of China’.
• Other than rice, the chief agricultural crops produced in this region are wheat, cotton, mustard, tung oil and tea.

Question 7. Which region is called the wetland of China?
Answer:

The wetland of China:

• The Yangtze Kiang River divides itself into a number of distributaries in its delta region and all of them drain into the China Sea.
• There are also a number of lakes and lagoons. So this delta region is referred to as the wetland of China.

Question 8. Name three abundant mineral resources of the Yangtze River Basin.
Answer:

Three abundant mineral resources of the Yangtze River Basin are-

1. Coal,
2. Iron ore,
3. Copper.

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China Very Short Question And Answers

Question 1. Which is the longest river in Asia?
Answer: Yangtze.

Question 2. River Yangtze originates from which mountain?
Answer: Kunlun.

Question 3. Which river of Asia is known as ‘The River of Golden Sands’?
Answer: Yangtze Kiang.

Question 4. What name is given to the upper reach of the Yangtze River (Szechuan Basin) because of the red-coloured sandstones found in this region?
Answer: Red Basin.

Question 5. Which place is known as the ‘Rice Bowl of China’?
Answer: Hunan province.

Question 6. Which place is called the ‘Holland of China’?
Answer: Yangtze Kiang Delta Region.

Question 7. Name the principal centre of China’s cotton textile industry.
Answer: Shanghai.

Question 8. Which is the longest man-made canal in the world?
Answer: Grand Canal (China).

Question 9. Why is Shanghai called the ‘Manchester of China’?
Answer:

Manchester of China:

Sanghai is an important city located in the deltaic region of Yangtze Kiang. It is an important centre for the cotton textile industry. just like Manchester of England. Thus, Shanghai is known as the ‘Manchester of China’.

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China Fill In The Blanks

Question 1. The Yangtze Kiang of China flows into the _______.
Answer: China Sea

Question 2. The Red Basin extends from the source of the Yangtze to _______.
Answer: Ichang

Question 3. The upper reaches of the Yangtze River Basin is referred to as _______ because of the red colour of its rocks and soil.
Answer: Red Basin

Question 4. The Middle Yangtze Basin region prospers in agriculture due to _______.
Answer: New alluvium

Question 5. The _______ region is known as the Granary of China.
Answer: Middle Yangtze Basin

Question 6. The _______ River Valley is called the cradle of the Chinese civilisation.
Answer: Hwang Ho

Question 7. The largest city of China is _______.
Answer: Shanghai

Question 8. _______ is the prime port of China.
Answer: Shanghai

Question 9. The _______ River Basin is known to produce the world’s best tungsten.
Answer: Yangtze

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China True Or False

Question 1. The Yangtze Kiang Basin has been divided into four parts.
Answer: False

Question 2. The capital of China is Shanghai.
Answer: False

Question 3. The Hunan province of China is known as its Granary.
Answer: True

Question 4. The Yangtze Kiang flows into the Sea of Japan.
Answer: False

Question 5. The upper reaches of the Yangtze Kiang Basin is famous as the ‘Holland of China’.
Answer: False

Question 6. The principal port of the Yangtze Kiang basin is Shanghai.
Answer: True

Question 7. Yangtze Kiang is also known as the ‘Golden Sanded River’.
Answer: True

Question 8. Yangtze Kiang is not only the longest river in China but also in Asia.
Answer: True

Question 9. The Yangtze Kiang is known as Chang-Jiang near its place of origin.
Answer: False

Question 10. Beijing, the capital of China, is situated near the mouth of the Yangtze Kiang.
Answer: False

Question 11. Wuchang is a big city and centre of commerce situated on the Yangtze Kiang Delta.
Answer: False

Question 12. The Yangtze Kiang is the best inland waterway in China.
Answer: True

Question 13. Shanghai is called the ‘Manchester of China’.
Answer: True

WBBSE Chapter 9 Continent Of Asia Topic B Yangtze River Basin Of China Match The Columns

Question 1.

Answer: 1. D, 2. E, 3. B, 4. A, 5. C

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth Long Question And Answers

Question 1. Why is Asia called ‘The land of extreme diversities’? or, State the geographical importance of Asia.
Answer:

Asia-‘The land of extreme diversities’:

Asia is called ‘The land of extreme diversities’ because of the following reasons-

1. Geological diversity:

The continent of Asia bears evidence of different geological ages. It contains parts of the two oldest landmasses-Angaraland and Gondwana- land as well as the newly formed Himalayan Ranges and most recently formed Sunderbans.

2. Geographical diversity:

Mt. Everest, the highest peak of the world as well as the Dead Sea, the lowest part on the landmass of the Earth are both located in Asia.

Read And Learn Also WBBSE Solutions For Class 7 Geography

3. Climatic diversity:

Jacobabad (summer temperature 52°C) is the hottest place in Asia. On the other hand, Oymyakon (temperature -71.2°C), the coldest place in the world lies here. Again, Mawsynram (average annual rainfall 1392 cm), the wettest place in the world lies in Asia.

4. Diversity in drainage:

There are big snow-fed rivers as well as small rain-fed rivers in this continent. Caspian Sea, the largest lake. in the world and Baikal, the deepest lake are both located in Asia.

5. Diversity in vegetation:

This continent has the extensive Taiga region in the north as well as xerophytic vegetation in the desert region.

Question 2. Describe the physiography of Asia.
Answer:

Physiography of Asia:

Asia has diverse physical features. Asia can be divided into the following six divisions on the basis of its physical features-

The Northern Plains:

The Northern Plains extend from the Caspian Sea in the west to Bering Strait in the east and from the Central Mountains in the south to the Arctic Ocean in the north. This region can be divided into three parts-

1. Turan Lowlands liying between the Caspian Sea and the Aral Sea.
2. Siberian Plain and
3. Eastern Uplands or Shield Region.

 

The central mountainous region:

In this part of the continent, a number of mountains radiate from the Pamir Knot and Armenian Knot.

1. The Himalayas, Karakoram, Kunlun, Tien Shan, Hindu Kush, Suleiman, Altyn Tagh, Altai, Sayan, etc. radiate from the Pamir Knot.
2. Elburz, Pontic and Taurus mountains radiate from the Armenian Knot. A number of intermontane plateaus are also found in this region.  Tibet Plateau lies in between the Himalayan and Kunlun Mountain Ranges, Iranian Plateau lies in between the Hindu Kush and Sulaiman Ranges, Anatolia Plateau lies in between the Pontic and Tauras Mountain Ranges, etc.

Low dissected plateaus of the south:

There are three ancient landmasses in the southern part of Asia-

1. Arabian Plateau,
2. Deccan Plateau,
3. Indo-China Plateau.

The course of the river explains the region’s slopes from west to east.

Riverine plains:

Rivers like Ob, Yenisei, Lena, Amu, Yangtze Kiang, Irrawaddy, Mekong, Ganga, Brahmaputra, Tigris and Euphrates have formed fertile plains along their basins. These plains are agriculturally prosperous as well as highly populated.

Coastal plains:

Asia is bounded on three sides by seas except on the west. Some parts of the coast are narrow while some are broad.

Island groups or archipelago:

There are innumerable volcanic, depositional and coral islands found in the Pacific and Indian Oceans.

For example- the Islands of Japan, the Indonesian Islands, the Kuril Islands, Islands of the Philippines, etc. Many islands are also found in the Arctic Ocean and the Mediterranean Sea.

For example, Greenland, Monumental Island in the Arctic Ocean and Ibiza, Majorca Island in the Mediterranean Sea.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. Describe the Northern Plains of Asia.
Answer:

The Northern Plains of Asia:

The Northern Plains of Asia extend from the Caspian Sea in the west to Bering Strait in the east and from Central Mountains in the south to the Arctic Ocean in the north. This plain covers about 20% of the landmass of Asia.

These plains have been divided into three parts according to their origin, structure and nature. They are-

1. Turan Lowlands:

Location:

The Turan Lowlands are located between the Caspian Sea and the Aral Sea.

Formation:

This part was originally formed by the upliftment of the sea floor and later deposition of sand from the Arctic Ocean separated it from the sea. This part is about 3m- 10m below sea level.

The scarcity of rainfall has led to the formation of two deserts-Karakum and Kyzylkum.

Important Definitions Related to Earth’s Revolution

2. Siberian Plains:

Location:

These plains extend from Ural Mountain in the west to Yenisei River Valley in the east.

Formation:

This region is formed by the sediments of Ob, Yenisei, and Lena and their distributaries. Glacial action has also been instrumental in the formation of this plain.

3. Eastern Uplands or Shield Region:

Location:

The Eastern Uplands extend from the Yenisei Valley in the west to Bering Strait in the east.

Formation:

Geologists think that the Shield Region was formed about 100 billion years ago. Later on, these lands became so consolidated that no terrestrial movement could disturb it.

However, the height of the shield has been reduced by rivers, glaciers and other weathering agents.

Question 4. Based on the direction of flow list the length, source, mouth and a few tributaries of some important rivers of Asia.
Answer:

List of some important rivers of Asia: Some important rivers of Asia are-

 

 

 

Question 5. Differentiate between north-flowing rivers and south-flowing rivers of Asia.
Answer:

Differences between north-flowing and south-flowing rivers of Asia:

The main differences between the north-flowing rivers and the south-flowing rivers of Asia are as follows-

 

Question 6. Why does Asia have a diverse climate?
Answer:

Reasons for the diverse climate of Asia:

There are some reasons for diversity in the climate of Asia-

Latitude:

The continent of Asia extends from 10°S to 82°N. So its southern part lies in the torrid zone, the central part lies in the temperate zone and the northern part lies in the frigid zone.

Distance from the sea:

The continental climate is found in regions which are located at a distance of 2000 km-2500 km from the sea coast. In Tibet the summer temperature can reach as much as 40°C while in winter it can go much below the freezing point.

The parallelly maritime climate is experienced around the sea coasts.

Altitude:

Temperature decreases with altitude. So the temperature remains low in the mountainous regions throughout the year. The central mountainous region of Asia which has an average elevation of 4000m, experiences a cold climate.

Physiography:

Since there are high mountains extending from west to east in the central part of Asia, the cold winds from the north cannot enter the southern part. Similarly, the south-west monsoon winds coming from the south are unable to cross over to the north.

Question 7. Describe the features of any two types of climate found in Asia and show how they influence the natural vegetation.
Answer:

Any two types of climate found in Asia and their influence on natural vegetation: Two climatic regions of Asia are-

Equatorial climatic region:

Location:

This type of climate can be found in places located 10°N and S of the Equator in the countries of Indonesia, southern Malaysia, Sri Lanka, Maldives, Singapore, etc.

Features of climate:

1. As the sun’s rays fall perpendicularly over here, the temperature remains high throughout the year. The average annual temperature is 25°C-30°C.
2. Rainfall occurs throughout the year (200 cm-250 cm annually).
3. In this region, only one season prevails i.e. summer.

Natural vegetation:

Features:

1. This region has evergreen vegetation i.e. the trees do not shed their leaves altogether during any season.
2. The trees are tall with stout trunks.
3. A number of trees belonging to the same species grow together and several types of parasitic creepers, ferns and orchids grow around them.

Trees:

Rubber, mahogany, ironwood, rosewood and varieties of palms grow here.

Mediterranean climatic region:

Location:

This type of climate is found along the Mediterranean Coast of Asia in the countries of Turkey, Lebanon, Israel and Syria.

Features of climate:

1. The coastal regions have a comparatively moist climate.
2. Rainfall occurs in winter under the influence of westerly winds.
3. Summer temperature is moderate (21°C-27°C).
4. The average annual rainfall is 35 cm-75 cm.

Natural vegetation:

Features:

1. The leaves are thick and covered with a waxy substance for protection from evaporation during the dry summer.
2. Some trees have thick barks and juicy fruits.
3. The roots are long and deep.

Trees: Cork, oak, pine, fir, olive and grapes.

Question 8. Discuss the relationship between the climate and natural vegetation of Asia.
Answer:

 

Relationship between climate and natural vegetation of Asia:

An intimate relationship exists between climate and natural vegetation. The nature and distribution of natural vegetation on the Earth’s surface depends on the elements of weather and climate like temperature, rainfall, humidity, etc.

The following table shows the distribution of natural vegetation on the basis of climate.

 

 

Question 9. Describe the location of the climatic regions of Asia.
Answer:

Location of the climatic regions of Asia:

On the basis of climatic characteristics, Asia can be divided into different climatic regions. Their locations are-

• Equatorial climatic region: This region extends on both sides of the Equator from 10°N to 10°S encompassing the countries of Indonesia and Malaysia in the north and Sri Lanka, Maldives, Singapore, etc. in the south.
• Monsoon climatic region: This region extends from 10°N to 30°N encompassing the countries of India, Bangladesh, Pakistan, the southern part of China, Thailand, Vietnam, etc.
•  China-type climatic region: In the central and northern parts of China, South Korea and in certain parts of Japan, the existence of this climatic region can be seen.
•  Manchurian climatic region: In the Manchuria region of China, the northern part of North and South Korea, etc. the existence of this climatic region can be seen.
• Mediterranean climatic region: Countries like Syria, Lebanon, Turkey, Israel, Jordan, etc. lying between 30°N-35°N along the coast of the Mediterranean Sea fall under this climatic region.
• Hot desert climatic region: The Arabian Desert, Thar Desert of India and Pakistan, Iraq, Iran, Kuwait, etc. experience this type of climate.
• Steppe climatic region: The southwestern region of Siberia and the Mongolia Plateau fall under this climatic region.
• Siberian climatic region: The Siberian region of Russia and a few areas of Sakhalin Islands fall under this climatic region.
• Tundra climatic region: The Arctic Circle region of the continent experiences this climate.
• Mid-latitude continental climatic region: The mountainous region of Central Asia falls under this climatic region.

 

Question 10. Give the location and extent of the continent of Asia.
Answer:

The location and extent of the continent of Asia:

Asia, the largest continent in the world is located due east of the continents of Europe and Africa.

It extends from Cape Piai, Malaysia in the south (1°16′ S) to Cape Chelyuskin, Russia in the north (77°44’N) and from Cape Dezhnev, Russia in the east (169°40’W) to Cape Baba, Turkey (26°4’E) in the west.

 

 

Due to its large east-west extension, when the sun rises in the western region, it is noon in the middle part and dusk in the extreme east of Asia.

Question 11. Write a brief note on the Pamir Knot.
Answer:

Pamir Knot:

• Pamir Knot is the nodal point from which almost all the mountain ranges of Asia radiate in different directions. The mountain ranges radiating from Pamir Knot are Hindu Kush and Sulaiman to the west.
• The Hindu Kush Range extends westwards as the Elbruz Mountain Range while the Sulaiman Range runs westwards first as Kirthar Range and then as the Zagros Mountains.
• To the east of the Pamir Knot lies the Himalayan, Karakoram, Kunlun, Altyn Tagh and Tien Shan Ranges.

 

Question 12. Describe the central mountains of Asia.
Answer:

The central mountains of Asia:

Almost all the mountain ranges of Asia radiate mainly from two nodal points or knots.

These two knots are-

1. Pamir Knot and
2. Armenian Knot.

Mountain ranges radiating from Pamir Knot are-

 

Mountain ranges radiating from Armenian Knot are-

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth Short Question And Answers

Question 1. Mention the area and boundaries of the continent of Asia.
Answer:

The area and boundaries of the continent of Asia

• Among the seven continents in the world, Asia ranks first according to area.
• It covers an area of about 4,45,79,000 sq.km i.e. 8.7% of the earth’s total surface area and comprises 30% of the land area.
• To the north of this continent is the Arctic Ocean and to its south is the Indian Ocean.
• It is further bounded by the Pacific Ocean and Bering Strait in the east. Red Sea, Gulf of Aden, Africa, Mediterranean Sea, Europe, Ural River and Ural Mountains, Suez Canal in the west.

Question 2. Give an account of the southern plateaus of Asia.
Answer:

Southern plateaus of Asia:

There are three vast plateaus located in the southern part of Asia. These are-

• Arabian Plateau: Located to the southwest of Asia. The general slope of the plateau is from southwest to north-east.
• Deccan Plateau: Located in the southern part of India. To its west lies the Western Ghats or Sahyadri Range and to its east lie the Eastern Ghats. The slope of the plateau is from west to east.
•  Indo-China Plateau and Yunnan Plateau: Both are parts of the same plateau lying in the southeastern part of Asia.

Question 3. Describe the Northern Plains of Asia.
Answer:

Northern Plains of Asia:

• There is an extensive plain in the northern part of Asia which extends from the Caspian Sea in the west to the Bering Strait in the east and from the Central Mountain Belt in the South to the Arctic Ocean in the north.
• This plain gently slopes from southeast to north-west. So, the rivers like Ob, Yenisei and Lena flow over this plain from south to north and flow into the Arctic Ocean.

On the basis of the variation in physiography at different places the Northern Plains of Asia can be divided into three parts-

1. A Lowland of Turan,
2. Siberian Plain,
3. Eastern Uplands or Shield Plateau.

Question 4. What do you know about the Siberian Plain?
Answer:

Siberian Plain:

The largest lowland in the world is the Siberian Plain. It extends from the Yenisei River Valley in the east to the western boundary of the Asian continent in the west.

• It has been formed by the depositional action of Ob, Yenisei, and Lena Rivers and glacial action.
• Its mean elevation is 200 meters. It is wide near the Ural Mountains and gradually becomes narrow near the Yablonoi or Yablonovy and Stanovoy Mountains.
• Due to the extremely cold temperature in the Arctic region, the rivers in their lower course i.e. in the northern part get frozen.
• As the waters in the upper course of the rivers are unable to reach the sea, every year severe floods occur in this region, making it swampy and marshy.

Question 5. Name a few alluvial plains of Asia.
Answer:

Alluvial plains of Asia:

In several parts of Asia, especially in the southeastern parts, many alluvial plains have formed.

Example

1. The area of the Tigris- Euphrates river system or Mesopotamian Plain in Iraq.
2. The Indus-Ganga-Brahmaputra Plain extends over India, Pakistan, and Bangladesh.
3. The North China Plain was formed jointly by the Amu, Hwang Ho, Yangtze, and Si Kiang Rivers.
4. The plain formed by the Irrawaddy and Salween Rivers in Myanmar,
5. The plain is formed by the Menam and Mekong rivers lying within Laos, Cambodia, and Thailand.

Question 6. Give an account of the island groups of Asia.
Answer:

Island groups of Asia:

All around the continent of Asia, especially in the Pacific Ocean and the Indian Ocean, there are many big and small islands as well as archipelagos (groups of islands).

Some of these islands are continental islands and a few are oceanic islands. These are-

Question 7. Find out from the political map which countries do these three plateaus belong to.

 

Answer:

 

Question 8. What are the characteristics of the northward-flowing rivers in Asia?
Answer:

The characteristics of the northward flowing rivers in Asia are-

A major part of the northern part of Russia including the Arctic Ocean remains frozen for about 8-9 months.

So, the rivers flowing from the Central Mountain Belt of Asia namely Ob, Yenisei, and Lena in the south are unable to flow into the sea, as they are hindered by the snow. This hindrance results in the occurrence of frequent floods in the upper and middle course of the rivers.

1. The rivers are unfit for navigation.
2. Marshy lands are found along the river valleys
3. The river valleys are sparsely populated.

Question 9. Why are the northward-flowing rivers of Asia flood-prone?
Answer:

The northward-flowing rivers of Asia flood-prone:

• The northward-flowing rivers of Asia are flood-prone because-As the lower course and mouth of the rivers flowing across the Northern Plains of Asia are located in the frigid zone, they remain frozen for a greater part of the year.
• But, the upper courses of these rivers are usually located in temperate regions (or comparatively warmer regions), where the river freezes only during winter.
• So, if the mouths of the rivers remain frozen, the excess water flow due to heavy rain during spring and autumn in the upper course is unable to reach the lower course and drain through the mouth. Thus the river valleys are flooded.

Question 10. What are the features of the rivers of the Tundra region?
Answer:

The features of the rivers of the Tundra region:

The rivers which flow over the Tundra region of Asia are Ob, Yenisei, and Lena. The features of the rivers of the Tundra region are-

1. The mouth of these rivers remains frozen almost throughout the year.
2. The rivers have gentle gradients and have low flow velocities.
3. Numerous large swamps have formed in the land areas near the river mouth due to flood.

Question 11. What are the characteristics of the southward-flowing rivers in Asia?
Answer:

The characteristics of the southward flowing rivers in Asia are-

1. Most of the rivers in South Asia (except a few rivers like Tigris- Euphrates, etc.) flow through the monsoon climatic region.
2. Though these rivers receive snow-melt water from mountainous regions, but most of them are rain-fed (monsoon rains) along the course.
3. Floods occur in the lower course of the rivers during monsoon season.
4. The rivers are perennial.
5. The rivers are used for irrigation and navigation.
6. The river valleys are densely populated.

Question 12. What are the characteristics of the eastward-flowing rivers in Asia?
Answer:

The characteristics of the eastward flowing rivers in Asia are-

1. The source of the principal eastward-flowing rivers is the Central Asian Mountain Belt.
2. The eastward-flowing rivers namely Amu, Hwang Ho, Yangtze, and Si Kiang flow over China and after crossing a long path flows into the Pacific Ocean.
3. The rivers deposit alluvium in their lower course and form fertile plains. These regions are highly developed in agriculture and industry.
4. So, the river valleys in this region are densely populated. The principal rivers in this region are Hwang Ho, Yangtze Kiang, etc.

Question 13. What are the characteristics of the westward-flowing rivers in Asia?
Answer:

The characteristics of the westward-flowing rivers in Asia:

Among the westward-flowing rivers in Asia, the principal rivers are the Narmada and Tapti of India. The characteristics of these rivers are-

1. These rivers are rain-fed and have strong currents in the monsoon season.
2. Both rivers flow through rift valleys before draining into the sea.
3. There are no deltas present at the mouth of these rivers.
4. These rivers are not perennial.
5. These rivers have steep slopes. and flow into the Arabian Sea.

Question 14. Name the inland rivers of Asia.
Answer:

Inland rivers of Asia:

• The rivers whose courses are confined within a country or continent i.e. the rivers which do not flow into any waterbody or sea outside its source region are called inland rivers.
• Some rivers of this type located within Asia are Amu Darya, Syr Darya, Ural, Tarim, Jordan, Helmand, etc. Luni River in India is an example of an inland river.

Question 15. What are the characteristics of the inland rivers of Asia?
Answer:

The characteristics of the inland rivers of Asia are-

1. The inland rivers of Asia like Amu Darya, Syr Darya, Ural, Tarim, etc. receive water only from rain.
2. The rivers are very shallow for most of the year.
3. Their lengths are comparatively shorter.
4. They flow into some waterbody within the country of their origin.

Question 16. Why are the central mountains of Asia called a water divide?
Answer:

The central mountains of Asia called a water divide:

• There are numerous long and high mountain ranges namely Pontic, Taurus, Elburz, Karakoram, Himalayas, Altyn Tagh, Tien Shan, etc. and intermontane plateaus namely Tibetan Plateau, Iranian Plateau, etc. in Central Asia.
• These extend from west to east and then towards the northeast of Central Asia. This mountain belt is the source region of many important rivers of Asia.

For example, Ob, Yenisei, and Lena to the north, Amu, Yangtze Kiang, and Hwang Ho to the east, and Euphrates- Tigris, Indus, Ganga, Brahmaputra, Irrawaddy, etc. to the south.

This long mountainous belt guides the courses of the rivers and thus is referred to as the ‘Water divide of Asia.

Examples of Real-Life Applications of Revolution Knowledge

Question 17. Why does Asia have such a diverse climate?
Answer:

Asia have such a diverse climate:

The different types of climate found in different parts of the Asian continent are mainly due to the following factors-

1. Effect of latitudes,
2. Distance from sea,
3. Influence of physiography especially the Central Asian Mountain Belt,
4. Influence of monsoons and westerlies,
5. Influence of hot and cold ocean currents,
6. Convectional rainfall in the equatorial region throughout the year and
7. Influence of the altitude of the Central Asian Mountain Belt.

Question 18. How does latitude influence the climate of Asia?
Answer:

Latitude influence the climate of Asia:

• The Asian continent extends from 1°16′ south latitude in the south to 77°44′ north latitude in the north. This vast north-south difference of latitudes in Asia results in the variation of temperature across the continent.
• As the southern part of this continent receives vertical rays of the Sun the temperature remains quite high almost throughout the year.
• Whereas, the northern part of the continent receiving oblique rays of the Sun have lower temperature throughout the year.

Question 19. How does distance from the sea influence the climate of Asia? Or, The central part of Asia is far away from the seas or oceans. So how do you expect the climate there to be?
Answer:

The central part of Asia is far away from the seas or oceans:

• The central part of Asia is about 2500 km away from the sea on either side.
• As the effect of the sea does not reach the interior of the continent, this region experiences extreme climate i.e. the difference between the minimum temperature in winter and maximum temperature in summer is very huge.
• Whereas, the coastal areas experience moderate climate i.e. the difference between the minimum temperature in winter and maximum temperature in summer is less.

Question 20. What are the characteristics of an equatorial type of climate in Asia?
Answer:

The chief characteristics of an equatorial type of climate in Asia are-

1. There is no variation in seasons as the climate is hot and humid i.e. high temperature and high rainfall is prevalent throughout the year.
2. The mean annual temperature ranges from 25°C to 30°C.
3. The annual rainfall ranges from 200 cm to 250 cm or more. Convectional rainfall occurs throughout the year, mostly in the afternoons.
4. Due to high amount of water vapour in the air, instability exists in the weather.
5. Rainfall occurs every day at 4 pm in the afternoon and hence, it is called 4 ‘o’clock rain.

Question 21. What are the characteristics of monsoon-type climate in Asia?
Answer:

The chief characteristics of monsoon-type of climate in Asia are-

1. There exists a cycle of seasons, namely
   1. Summer,
   2. Monsoon,
   3. Autumn and
   4. Winter.
2. Summers are hot and humid, while winters are mild and dry.
3. The average temperatures during summers varies between 20°C-28°C and 15°C -20°C during winters.
4. The southwest monsoon winds blowing from the sea, carry moisture and cause rainfall.
5. The mean annual rainfall ranges from 100 cm to 200 cm. The foothill regions receive comparatively higher rainfall.

Question 22. What are the characteristics of China type of climate in Asia?
Answer:

The chief characteristics of this type of climate are-

1. Summers are wet and mildly hot and winters are dry and cool.
2. The average temperature in summer is 30°C and that in winter ranges between 4°C -12°C.
3. The winds which enter this region in summer usually blow from the sea, carrying moisture and resulting in sufficient rainfall. The annual rainfall is about 100 cm.

Question 23. What are the characteristics of the Mediterranean type of climate in Asia?
Answer:

The chief characteristics of the Mediterranean type of climate are described as below-

1. Moist westerlies blow over this region in the winter season causing rainfall. Although the amount is less, it averages between 30cm 50cm annually.
2. Dry northeast trade winds blow over this region in the summer causing no rainfall.
3. It is neither too hot nor too cold at any time of the year. The average temperature in the summers is between 21°C -27°C and in the winters, between 5°C -10°C.
4. Snowfall occurs in the mountain regions during winter.

Question 24. What are the characteristics of the hot desert type of climate in Asia?
Answer:

The characteristics of the hot desert type of climate are-

1. An extreme type of climate prevails in this region.
2. The diurnal range of temperature in the region is high-about 25°C to 35°C. The maximum temperature during the day averages between 40°C-45°C and at night, the temperature falls down to about 8°C.
3. The hottest place in Asia is Jacobabad in Pakistan, where the maximum temperature recorded has been 52°C.
4. The average temperature in summers is about 30°C -35°C and in winters about 15° -25°C.
5. Dust storms are common during the day.
6. The average annual rainfall ranges between 10cm-25 cm and in some years even this amount of rainfall does not occur.

Question 25. What are the characteristics of the Siberian-type of climate?
Answer:

The characteristics of the Siberian-type of climate:

The Siberian type of climate extends from 40°-45° north latitudes to the Arctic Circle in the Siberian region of Russia. The characteristics of this type of climate are-

1. Winters are long and very cold while summers are short and chilly.
2. The average annual temperature during summer is about 15°C while during winters the temperature remains below the freezing point.
3. There is hardly any rainfall but it snows heavily. This heavy snowfall during the winter results in the surface remaining covered with snow for 7 to 8 months in a year.
4. Intense snow storms or blizzards blow over this region during winter.

Question 26. What are the characteristics of a Tundra type of climate?
Answer:

The characteristics of a Tundra type of climate:

The Tundra type of climate prevails over the northern part of the Arctic Circle (661°N) i.e., towards the north of the continent of Asia.

1. This region mainly falls within Russia. Some important characteristics observed in this type of climatic region are-
2. The winters are severely cold and very long. Heavy snowfall occurs for 8-9 months in a year and the surface remains covered with snow almost throughout the year.
3. Darkness prevails continuously for months during the winter season.
4. Summer season prevails only for 2-3 months. The average temperature during summer ranges between 0°C-10°C. So, the summer season is also pretty cold.
5. Sometimes little rainfall occurs in the summer season due to temperate cyclones.

Question 27. What are the characteristics of the Steppe type of climate in Asia?
Answer:

The chief characteristics of the Steppe type of climate are-

1. An extreme type of climate prevails in this region.
2. Short summers and long winters exist.
3. The average temperature in summers varies between 33°C-38°C and in winters, it remains around -20° C.
4. Little rainfall occurs in the summer season (average 12.5cm-25cm) and snowfall occurs in the winter.
5. The diurnal and annual range of temperature are very high.
6. The region remains snow-covered from November to March and thaws in the month of April.

The characteristics of this climate are-

1. The summer temperature is comparatively higher than the China type of climatic region located in the south, and the winters are cold. The average annual temperature in summer is 24° C to 31°C and in winter is -25°C to -30° C.
2. Mild short summers prevail. Moderate rainfall (average 75 cm) occurs during the summers.
3. There is abundant snowfall during the winter.

Question 28. What are the characteristics of continental mid-latitudinal climates?
Answer:

The characteristics of continental mid-latitudinal climate are-

1. As the regions experiencing this type of climate are bounded by mountains on all sides, moist air is unable to reach its interior. Thus, dry conditions prevail due to a lack of rainfall.
2. As a result of this dry weather, the summers are quite hot and the winters are severely cold i.e. extreme type of climate prevails.
3. As the amount of rainfall is very less, the condition is a more hot desert type but, being located a little north i.e. in the temperate regions the temperature does not rise as much as that of the hot deserts. Some temperate deserts have formed in this region, for example-Gobi Desert and Taklamakan Desert.

Question 29. What are the general characteristics of the climate prevailing over Asia?
Answer:

The general characteristics of the climate prevailing over Asia are-

1. Extreme variation in climate,
2. A considerable rise in temperature during the summer,
3. Considerable fall in temperature during the winter,
4. The arrival of warm and moist southwest monsoons.
5. The arrival of dry and cold north-east monsoons,
6. Rainfall due to the influence of westerlies, etc.

Question 30. What are the chief characteristics of the equatorial evergreen forests?
Answer:

The chief characteristics of equatorial evergreen forests are-

1. Due to very high temperatures and adequate rainfall throughout the year, trees are tall (height: 30m-45m), with broad leaves.
2. The trees yield hard wood which is used for making furniture.
3. The trees have green leaves throughout the year and are thus, called evergreen trees.
4. Due to the presence of plank buttress roots, the trees get additional support and stability to stand erect.
5. As the trees usually form a thick canopy, the sunlight is prevented from reaching the forest floor. So, the forests are dark, damp, and gloomy.
6. These forests are known as the ‘Lungs of the World’.
7. The vegetation density of these forests is the highest. The important trees are mahogany, rosewood, ironwood, teak tables, rubber, cocoa, and cinchona.

Question 31. Give reasons for the predominance of evergreen trees with broad leaves in the equatorial natural vegetation belt of Asia.
Answer:

• The equatorial natural vegetation belt in Asia experiences abundant rainfall throughout the year. The excess amount of rainwater is absorbed by the tall plants, which usually have broad leaves to lose it through transpiration.
• A large number of stomata are present on these bigger-sized leaves making it easier to lose the excess water through transpiration. Moreover, due to this excessive rainfall throughout the year, the trees do not dry up or shed their leaves at one particular time.
• Rather, they shed their leaves in small quantities all year round, retaining their evergreen character. Thus, there is a predominance of evergreen trees in this forest.

Question 32. What are the characteristics of Mediterranean forests in Asia?
Answer:

The characteristics of Mediterranean forests in Asia are –

1. The tree have long roots which reach great depths in the soil in search of water.
2. The stem of the trees remain covered with a thick bark and the thick leaves have a wax-like coating.
3. These forests are sparse and scattered
4. Due to lack of sufficient water, climbers, bushes, and drought-immune trees grow in this forest. The important trees are olive, grapes, lemon, cork, oak, laurel, lavender, rosemary, etc.

Question 33. What are the characteristics of desert-type of vegetation or xerophytic vegetation in Asia?
Answer:

The characteristics of the desert type of vegetation in Asia are-

1. The trees have very long roots.
2. The leaves of the xerophytic plants are usually thin and small and mostly are thorns.
3. Due to the severe scarcity of water, very few types of plants grow in the deserts.
4. Their leaves and stems are succulent.
5. Very few stomata are present on the leaves of these trees.
6. These trees are adapted to the scarce water conditions prevalent in a desert region. Thorny bushes, date, palm, prickly bean, and acacia grow here.

Question 34. What are the chief characteristics of Taiga forests?
Answer:

The chief characteristics of the Taiga forests in Asia are-

1. The Taiga forests are dominated by coniferous trees.
2. The trees yield softwood, which is used as timber and for making paper and rayon.
3. The canopy of these trees have a cone-like structure with fewer branches and the trees grow straight upwards.
4. The forest floor is devoid of climbers and weeds.
5. The leaves of these trees are short and needle-shaped. The important trees are pine, fir, spruce, larch, birch, cedar, and willow.

Question 35. The average altitude of Central High- lands of Asia is more than 4000m. Then what would be the temperature there?
Answer:

The average altitude of Central High- lands of Asia is more than 4000m.

• We know that according to the normal lapse rate of temperature, the temperature decreases by 6.4°C per 1000m of ascent from the sea level.
• So, the temperature at an altitude of 4000m would be 6.4°C x 4 = 25.6°C less than the temperature at sea level.

Question 36. What is meant by the Dead Sea or ‘The Sea of Death’?
Answer:

The Sea of Death:

• There is a deep saltwater lake, i.e. around 430 meters below the sea level located at the boundary of Jordan and Israel in West Asia called the Dead Sea or the Sea of Death. This lake has 330 grams of salt per 1000 grams of water.
• This high salinity makes for a harsh environment in which no animal can survive or flourish, hence its name. This lake is also called the Salt Sea.

Question 37. What do you mean by Eurasia?
Answer:

Eurasia:

Eurasia is the combined continental landmass of Europe and Asia. In the absence of any geographical boundary (except Ural Mountains, Ural River and Caspian Sea) between the continents of Europe and Asia; this vast landmass has formed.

Question 38. What are the physiographic divisions of Asia?
Answer:

According to variations in physiography, Asia can be divided into six physiographic divisions.

They are-

1. The Northern Plains,
2. The Central Mountains,
3. The Southern Plateaus,
4. The Great Riverine Plains,
5. The Coastal Plains,
6. The Island Groups.

Question 39. Name the intermontane plateaus of central Asia.
Answer:

The important intermontane plateaus in central Asia are

 

Question 40 Write a note on the Arabian Plateau.
Answer:

Arabian Plateau:

• The Arabian Plateau located to the southwest of Asia gently slopes eastward from the west and merges with the narrow plains along the Persian Gulf.
• Most of the Arabian Plateau region is dry and rainless. There is no river in this region.

Question 41. Write a note on the Deccan Plateau.
Answer:

Deccan Plateau:

• The Deccan Plateau located in the southern part of India is made up of old igneous rocks and lava flows from volcanoes.
• As a result of prolonged erosion, the plateau has become dissected and wavy (with a number of uplands and lowlands).
• The important eastward-flowing rivers in this plateau region are Mahanadi, Godavari, Krishna, and Kaveri. The westward-flowing rivers are Narmada, Tapti, etc.

Question 42. Write what you know about the Indo- China Plateau.
Answer:

Indo- China Plateau:

• The Indo-China Plateau, located to the southeast of Asia covers parts of countries like Thailand, Laos, Cambodia, Myanmar, and Vietnam.
• This plateau merges with the Yunnan Plateau and gently slopes from north to south.
• The rivers draining this plateau are Salween, Mekong, Xi, Menam or Chao Phraya, etc.

Question 43. Write a note on the highlands of the east or Shield Plateau.
Answer:

Highlands of the east or Shield Plateau:

• To the northeast of the Northern Plains of Asia lie the highlands of the East or Shield Plateau. It extends from the Bering Strait in the east to the Yenisei River Valley in the west.
• These are the remnants of an ancient and dissected plateau. Its mean elevation is comparatively higher and is also known as the Angara Shield of the West Siberian Plain.

Question 44. Write a note on the Lowlands of Turan.
Answer:

Lowlands of Turan:

• The Lowlands of Turan or Turan Plain lies to the southwest of the Northern Plains of Asia.
• It covers southwest Kazakhstan and north-western parts of Uzbekistan and Turkmenistan.
• Within this lowland lies the Caspian Sea and the Aral Sea. The Amu Darya and the Syr Darya rivers drain this plain.
• Some of the places in this region are about 8-9 meters below sea level. There are two deserts in this region namely Karakum and Kyzylkum.

Question 45. Divide the rivers of Asia according to the direction in which they flow.
Answer:

According to the direction of flow, the rivers of the Asia can be classified into five types.

These are-

1. Northward flowing rivers, for example. Ob, Lena;
2. Southward flowing rivers, for example, Mekong, Indus, Brahmaputra;
3. Eastward flowing river; example, Amu, Hwang Ho;
4. West-ward flowing river, for example, Narmada, Tapti;
5. Inland rivers, for example, Syr Darya, Amu Darya.

Question 46. Write a note on Sat-El-Arab.
Answer:

Sat-El-Arab:

The confluent stream of the River Tigris (rising from the Armenian Plateau) and River Euphrates (rising from Kurdistan Mountain) is known as Sat-El-Arab. This confluent stream then drains into the Persian Gulf.

Question 47. Name the rivers of the monsoon climatic region of Asia.
Answer:

The southward-flowing rivers of Asia namely Ganga, Brahmaputra, Irrawaddy, Salween, etc. flow through the monsoon climatic regions. Floods are common in these rivers during monsoon season.

Question 48. Describe the course of the Hwang Ho or Yellow River.
Answer:

• The Hwang Ho River originates from the Kunlun Mountains in China. At first, it flows northwards and then towards the east.
• The river flows into the Bohai Sea after crossing a length of 5464 km.
• As the water of this river has yellow loess soil mixed in it, it is yellow in colour and hence the name Yellow River. Fen, Wei, Luo, Wuding, etc. are some of its tributaries.

Question 49. Divide Asia into different climatic zones. Or, What are the different types of climate which can be observed from south to north in Asia?
Answer:

According to the variation in climate, Asia can be divided into 10 main climatic zones.

These are-

1. Equatorial climatic zone,
2. Monsoon climatic zone,
3. Zone of China-type climate,
4. Manchurian climatic zone,
5. Mediterranean climatic zone,
6. Zone of hot desert type of climate,
7. Mid-latitude continental climatic zone,
8. Steppe type of climatic zone,
9. Siberian climatic zone,
10. Tundra climatic zone.

Question 50.  Which regions in Asia experience a Steppe type of climate?
Answer:

• A steppe type of climate prevails over the grasslands of the Anatolian Plateau in the west and the eastern part of the Gobi Desert in the east of Asia.
• These regions receive little rainfall and snow-melt water and thus, only grasses grow here. These grasslands are called Steppe.

Question 51. What are the different types of natural vegetation found in Asia?
Answer:

• Natural vegetation of a region is highly influenced by the prevailing climatic conditions.
• Thus, with increasing differences in temperature and rainfall across the continent, a wide variety of natural vegetation is found in different parts of Asia.

According to this variation, natural vegetation across this continent can be divided into 7 types-

1. Equatorial evergreen forest,
2. Tropical monsoon or deciduous forest,
3. Steppe grassland region,
4. Taiga forest region,
5. Mediterranean forests,
6. Tundra vegetation,
7. Desert vegetation.

Question 52.  Mention the characteristics of tropical monsoon or deciduous forests in Asia.
Answer:

• The characteristics of tropical monsoon or deciduous forests in Asia are- The trees are not very tall (height: 10m-15m).
• The trees lose all their leaves in winter and hence, the name is deciduous. (The term deciduous means ‘tending to fall off’.)
• These forests have dense undergrowth of herbs, shrubs, and bushes. The upper stratum of the trees are clustered.

Question 53. Mention the characteristics of Tundra vegetation in Asia.
Answer:

The characteristics of Tundra vegetation in Asia are-

1. Big trees do not grow as the surface remains covered with snow for most of the year.
2. During the short summers when the snow melts, a few plants like shrubs and mosses grow.
3. Towards the southern part of the Tundra vegetation belt, a few trees are found. Moss, lichen, algae, etc. grow in the Tundra region.

Question 54. Why is the Yangtze Kiang Basin densely populated?
Answer:

The Yangtze Kiang Basin is the most densely populated region in China. Although the basin covers one-fifth of the total area of China (i.e. about 18 lakh sq. km), it is the home to one-fourth (about 30 crores) of the total population of China.

The reasons for the high population density in this region are-

1. Rich in agriculture,
2. Rich in mineral resources,
3. Industrially developed,
4. The developed transport system,
5. Accessibility to large seaports,
6. Pleasant climate, etc.

Question 55. Mention the characteristics of the Steppe Grasslands of Asia.
Answer:

The characteristics of Steppe Grasslands of Asia are-

1. Very few trees because of low rainfall.
2. Short and soft grasses that flourish in severe cold and dry winter.
3. Some big trees are found in high mountainous regions and near the river banks.

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth Very Short Question And Answers

Question 1. Which is the largest continent in the world in terms of area?
Answer: Asia.

Question 2. Which is the highest plateau in the world?
Answer: Pamir Plateau.

Question 3. Which is the deepest lake in the world?
Answer: Lake Baikal.

Question 4. Which is the coldest place in the world?
Answer: Oymyakon, Russia (Siberia).

Question 5. Name the largest delta in the world.
Answer: Ganga-Brahmaputra Delta.

Question 6. What is the combined continental landmass of Europe and Asia called?
Answer: Eurasia.

Question 7. Which is the largest plateau in the world located between the Himalayan and Kunlun Mountain Ranges?
Answer: Tibetan Plateau.

Question 8. In which direction does the Ob, Yenesei, and Lena River flow?
Answer: Northward direction.

Question 9. Which one is the longest among the north flowing rivers?
Answer: River Yenisei.

Question 10. Which of the south-flowing rivers of Asia originates near Manas Sarovar of Tibet and falls in Bay of Bengal?
Answer: Brahmaputra River.

Question 11. Which is the longest south-flowing river of Asia? What is the length of that river?
Answer: Mekong River (435 km).

Question 12. Which is the longest river of Asia?
Answer: Yangtze Klang.

Question 13. Which river is called the ‘Sorrow of China’?
Answer: Hwang Ho River.

Question 14. Which river of Asia is known as ‘The River of Golden Sands’?
Answer: Yangtse River.

Question 15. Which river is known as the ‘Yellow River’?
Answer: Hwang Ho River.

Question 16. Name two east-flowing rivers of Asia which empty into the China Sea.
Answer: Yangtze Kiang and Si-Kiang.

Question 17. What name is given to the Hwang Ho River because of the yellow colour of its water in the lower course arising from loess being carried downstream?
Answer: Yellow River.

Question 18. Name the inland river of India.
Answer: Luni River.

Question 19. Which climatic region in Asia is characterized by very high temperature and humidity, and with no seasonal variations?
Answer: Equatorial climate region.

Question 20. Which climatic region in Asia is characterized by dry summers and wet winters?
Answer: Mediterranean climate region.

Question 21. Name the forestland characterized by coniferous trees, found in the northern part of Russia i.e. in the Siberian region.
Answer: Taiga.

Question 22. Name the type of grassland found in central Asia and in some parts of Anatolia.
Answer: Steppes.

Question 28. How are the Mediterranean forests and woodlands in Asia distributed?
Answer:

The Mediterranean forests and woodlands are found in the countries surrounding the Mediterranean Sea namely Lebanon, Israel, Palestine, and Syria.

Question 29. How is the desert type of vegetation in Asia distributed?
Answer:

The desert type of vegetation is found in arid, hot stretches of this continent such as in the Arabian Desert in Saudi Arabia, the Thar Desert in India and Pakistan, the Taklamakan Desert in China, and the Gobi Desert in Mongolia.

Question 30. Where is the Taiga forest located in Asia?
Answer:

The Taiga forests are found in the northern part of Asia, mainly in the heavy snowfall regions of Siberia.

Question 31. How is the Tundra vegetation in Asia distributed?
Answer:

A concentration of Tundra vegetation is found in the extreme north of the Siberian landmass in Russia, bordering the Arctic Circle.

Question 33. Where are the Steppe Grasslands located in Asia?
Answer:

The Steppe Grasslands are found in the regions of low rainfall in central Asia namely the northern part of the Turan Plain and the foothill region of the Khingan and Yablonovy Mountain Ranges.

Question 34. Where do we find monsoon climatic regions in Asia?
Answer:

The countries namely India, Bangladesh, Myanmar, Laos, Cambodia, Vietnam, and the southern parts of China and Japan which lie between 10° N and 30° N parallels of Asia fall within this tropical monsoon climatic zone.

Question 35. Where do we find China’s type of climate in Asia?
Answer:

The China type of climate is found in the eastern part of the Asian continent namely, the central part of China, the southern part of South Korea, and the central part of southern Japan.

Question 36. Where do we find the Mediterranean type of climate in Asia?
Answer:

The Mediterranean type of climate is observed in the western parts of Asia i.e. namely Syria, Lebanon, Jordan, Israel, Turkey, Palestine, etc. which are situated along the coast of the Mediterranean Sea.

Question 37. Give the extent of the hot desert-type climate in Asia.
Answer:

The hot desert type of climate is prevalent over the south-western parts of Asia i.e. the Arabian Desert, Thar Desert of India and Pakistan, Iraq, Iran, Kuwait, etc. In this type of climate, very high temperature and very less rainfall is experienced.

Question 38. What are the characteristics of the Manchurian type of climate?
Answer:

Manchuria (north of China), the northern part of North and South Korea, the Sakhalin Island of Russia, and the northern part of Japan is situated in the Manchurian type of climatic region.

Question 39. Where do we find equatorial climatic regions in Asia?
Answer:

The southern part of Asia; i.e. regions located near the Equator (between 10° N to 10° S) experience the equatorial type of climate.

For example, Malaysia, Indonesia, Maldives, Singapore, Sri Lanka, Java, Borneo, Sumatra, etc.

Question 40. Where do we find the mid-latitudinal continental climate in Asia?
Answer:

The intermontane plateaus located in the central part of Asia are affected by a mid-latitudinal continental climate. Iran, Turan, Tibet, the region of the Gobi Desert lie within this climatic region.

Question 41. Name the highest and the lowest point on the Earth’s surface.
Answer:

The highest point on the Earth’s surface is Mt. Everest (8848m above sea level) and the lowest point on the Earth’s surface is Dead Sea (402m below sea level).

Question 42. Give the location of the equatorial evergreen forests in Asia.
Answer:

The equatorial evergreen forests are found between 5° -10° N/S latitudes in southeast Asia.

For example- Indonesia, Malaysia, Myanmar, West Papua province (Indonesia), Celebes, Philippines, Sri Lanka, and the southern edge of India, etc.

Question 43. Give the location of the tropical monsoon or deciduous forests in Asia.
Answer:

The tropical monsoon or deciduous forests are predominant in countries like India, Bangladesh, Myanmar, Thailand, Laos, Vietnam, Cambodia, the Malay Peninsula, and South-East China, etc. in Asia.

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth Fill In The Blanks

Question 1. The largest lake in Asia is __________.
Answer: Caspian Sea

Question 2. The coniferous forests in Russia are called __________.
Answer: Taiga

Question 3. The most low-lying place on Earth is __________.
Answer: Dead Sea

Question 4. The __________ Plateau is also known as the Roof of the World.
Answer: Pamir

Question 5. The Dead Sea is also known as __________.
Answer: Salt Sea

Question 6. The wettest place in Asia is __________.
Answer: Mawsynram

Question 7. The largest continent in the world is __________.
Answer: Asia

Question 8. The Aral Sea is a __________ water lake.
Answer: Saline

Question 9. __________ range radiates to the west from the Pamir Knot.
Answer: Hindu Kush

Question 10. The Pontic and the Taurus Mountains Ranges have originated from the __________ Knot.
Answer: Armenian

Question 11. The __________ Plateau lies between the Pontic and the Taurus Mountain Ranges.
Answer: Anatolian

Question 12. The Deccan Plateau in India is an example of __________ plateau.
Answer: Lava

Question 13. The Caspian Sea and Aral Sea are located in the __________ Basin.
Answer: Turanian

Question 14. Ob River flows through a __________ region.
Answer: Cold

Question 15. The Yenisei River flows into the __________.
Answer: Yenisei Gulf

Question 16. The __________ flowing rivers of the Asian continent are flood-prone.
Answer: Northward

Question 17. Ob, Yenisei, and Lena are __________flowing Rivers.
Answer: Northward

Question 18. Among the northward-flowing rivers, River _____ is the longest.
Answer: Yenisei

Question 19. The Ganga River has originated from the __________ glacier.
Answer: Gangotri

Question 20. The Indus River flows into the __________.
Answer: Arabian Sea

Question 21. Among the southward-flowing rivers, River __________ is the longest.
Answer: Mekong

Question 22. __________ is the river formed by the confluence of the rivers Tigris and Euphrates.
Answer: Sat-El-Arab

Question 23. Yangtze River originates from the glaciers of the __________ mountain peak.
Answer: Geladangdong

Question 24. The __________ River is known as the ‘Golden Sanded River’ in Asia.
Answer: Yangtze

Question 25. The __________ River has originated from a glacier in the south-western part of the Geladangdong peak in the south of the Kunlun Mountain Range.
Answer: Yangtze

Question 26. The __________ River in Asia is also known as the Yellow River.
Answer: Hwang Ho

Question 27. __________ is the longest river of Asia.
Answer: Yangtze

Question 28. Amu Darya River flows into the __________ Sea.
Answer: Aral

Question 29. India, located in the southern part of Asia experiences __________ climate.
Answer: Monsoon

Question 30. The trees of the __________ forests have wax-coated leaves.
Answer: Mediterranean

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth True Or False

Question 1. The highest mountain peak in Asia is Mt. Everest.
Answer: True

Question 2. The Aral Sea is a saline lake.
Answer: True

Question 3. The coldest place in Asia is Jacobabad.
Answer: False

Question 4. Manas Sarovar is located on the Pamir Plateau.
Answer: False

Question 5. The deepest lake in Asia is Lake Baikal.
Answer: True

Question 6. The Deccan Plateau is an intermontane plateau.
Answer: False

Question 7. Cacti and shrubs are found in the polar regions.
Answer: False

Question 8. Kunlun and Altyn-Tagh mountain ranges radiate towards the west from the Pamir Knot.
Answer: False

Question 9. The Tibetan Plateau lies between the Himalayan and the Kunlun Mountain Ranges.
Answer: True

Question 10. The Zagros and Elburz Mountain Ranges radiate towards the east from the Armenian Knot.
Answer: True

Question 11. One of the important rivers in Asia that flow into the Pacific Ocean is Lena.
Answer: False

Question 12. The longest river in Asia is the Yangtze.
Answer: True

Question 13. A southward-flowing River of Asia is Hwang Ho.
Answer: False

Question 14. Tropical monsoon climate prevails over the northern part of Asia.
Answer: False

Question 15. The extensive grassland found more or less in the central part of Asia is called Steppes.
Answer: True

Question 16. Mekong is an eastward-flowing river in Asia.
Answer: False

Question 17. Syr Darya River is an inland river.
Answer: True

Question 18. The Tundra region is a permafrost region.
Answer: True

Question 19. Taklamakan is a temperate desert.
Answer: True

Question 20. The crops in the Tundra region remain alive even during snowfall in winter.
Answer: False

Question 21. The Tigris-Euphrates River basin is famous for its aquatic vegetation.
Answer: True

Question 22. The Hwang Ho River is also known as the Yellow River.
Answer: True

Question 23. Amu is the largest eastward-flowing river in Asia.
Answer: True

Question 24. The mean elevation of the Mountains of Central Asia is 4000 meters.
Answer: True

Question 25. The largest river in Asia is Ganga.
Answer: False

Question 26. The Ladakh Plateau in India is known as the ‘Roof of the World’.
Answer: False

WBBSE Chapter 9 Continent Of Asia Topic A Revolution Of The Earth Match The Columns

Question 1.

Answer: 1. C, 2. E, 3. B, 4. A, 5. G. 6. D, 7. F

Question 2.

Answer: 1. C, 2. D, 3. E, 4. B, 5. G. 6. A, 7. F

 

WBBSE Chapter 8 Soil Pollution Long Question And Answers

Question 1. Discuss the sources or causes of soil pollution.
Answer:

Sources or causes of soil pollution:

Soil can become polluted because of natural as well as man-made reasons. Natural causes of soil pollution are heavy rainfall, landslide, strong wind movement, etc. But soil pollution is mainly caused due to indiscriminate activities of men.

The main sources of soil pollution are as follows-

1. Urbanisation:

The constant rise in population has increased the demand for dwelling places. So forests are being cleared to provide more land for dwelling and agriculture. As a result, the soil is getting eroded as well as polluted.

2. Agriculture:

• The demand for food increases with the rise in population. So, the use of chemical fertilizers and pesticides also increases to produce more crops on the same plot of land.
• This leads to the death of several creatures like earthworms and other insects which live in the soil. This, in turn, lowers the fertility of soil and causes soil pollution.

Read And Learn Also WBBSE Solutions For Class 7 Geography

3. Industrial pollution:

• Every year, about 16000 kg of hard disposable industrial wastes accumulate on the ground.
• Every year about 2×109 kg of fly ash is ejected from leather, dye, plastic and paper industries; oil refineries; metal extraction plants and thermal power plants and this lowers the soil fertility.
• Also, the smoke and poisonous gases (SO₂, NO₂) coming out from factories cause acid rain which contaminates the soil.

• Domestic wastes: Bacteria, virus,es and other microbes breed on the garbage heaps disposed from houses, hospitals, markets, towns, and cities. The poisonous chemicals in these heaps pollute the Earth.
• Atomic pollution: A vital cause of soil pollution is the existence of atomic power stations, atomic research centers, hospitals, and nursing homes using radioactive materials and radioactive wastes.
• Medical wastes: An important cause of soil pollution is the disposal of medical waste without proper segregation from various hospitals and medical centers.
• Transport: Vehicles usually emit smoke containing CO₂, SO_2, etc. which mixes with rainwater and falls on the ground as acid rain. This rainwater mixes with soil and causes soil pollution.

Question 2. Describe the methods used to control soil pollution.
Answer:

Methods used to control soil pollution:

The methods used to control soil pollution are-

• Increased use of organic fertilizer: Increase in the use of organic fertilizers instead of chemical fertilizers so that the soil health remains unaffected.
• Less use of plastic: Wherever plastic is discarded as a waste product it clogs soil pores. It causes soil pollution. Thus the use of plastic products should be lessened. We can use paper and jute bags instead of plastic.
• Specific ground for waste disposal: Wastes should be disposed off in specific dumping grounds or vats and not thrown here and there.
• Proper method of waste disposal: The proper method should be undertaken for disposal of solid hazardous wastes to prevent deterioration of soil health and the environment being affected at any and every place.
• Recycle: Recycling of soil pollutants should be encouraged to lessen their harmful impacts.
•  Implementation of strict laws: Strict laws should be implemented for waste disposal to control soil pollution.
• Soil testing: Regular soil tests should be done as a method to control soil pollution.
• Increase awareness: The people should be made aware about the ways to prevent soil pollution.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3. Write a note on the effects of soil pollution on human life.
Answer:

Effects of soil pollution on human life:

Soil pollution brings about the following effects on human life-

1. Polluted soil is the breeding ground of various microbes that cause diseases in the human body such as cholera, amoebiasis, typhoid, and paratyphoid.
2. Inorganic pollutants like mercury cause a variety of diseases like mental illness, loss of eyesight, etc.
3. Due to the effect of cadmium, different diseases occur in the human body like increased blood pressure.
4. Under the effect of lead, different diseases are observed in the human body like anemia.
5. DDT and other slowly degradable chemical substances which enter our food chain, pass from lower to higher nutrient levels. It accumulates within the organisms. This is called biomagnification.
6. Under the effect of soil pollution, soil fertility decreases, which in turn lowers the productivity of the land thereby decreasing the income of the farmers.
7. When the pesticide and fertiliser-contained soil drains into the nearby waterbodies it renders the water of the waterbody unfit for further human use.

Question 4. Observe soil pollution in your locality and write it down.

1. Name of locality or village………….
2. Is the garbage of your house disposed off at a certain place?
3. Is that waste cleaned every day?
4. Do you find any difference in colour of the soil around the factories and that near your house?
5. Make a list of the causes of soil pollution in your area.

Answer:

Name of the student: Sk Arman Class: VII

School: Guptipara High School.

Question 5. How do household and municipal solid wastes cause soil pollution?
Answer:

Household and municipal solid wastes cause soil pollution:

• Solid wastes of households example, broken pieces of plastic, torn packets, paper, clothes, batteries, broken glass, food and kitchen wastes like vegetable peel, and fruit peel, and municipal wastes like excreta, and medical wastes are collected by the municipality within an area.
• These waste materials are segregated and then sent for reprocessing. Most of the domestic wastes are directly transported to landfill sites for disposal without proper segregation into organic, reusable, and recyclable wastes.
• This is one of the main causes of soil pollution.

Example-The Dhapa dumping ground just outside Kolkata has become polluted. As a result, fruits and vegetables grown in polluted soil transmit a variety of diseases in humans.

These diseases have maximum manifestation at the producer level and this is called ‘biomagnification’.

Question 6. How do plastics aggravate the problem of soil pollution?
Answer:

Plastics aggravate the problem of soil pollution:

At present different types of plastic are used in various parts of the world. These can be biodegradable as well as non-biodegradable. Wherever plastic is discarded as a waste product, it clogs soil pores, drains, pipes, and ditches.

The various ways in which plastic causes soil pollution are-

1. Clogging of soil pores by plastic wastes and wrappers results in the loss of soil fertility making the farmland unsuitable for cultivation.
2. Plastic wastes accumulating on the wetlands make them overflow with water.
3. The plastic-forming compounds kill different microorganisms present in the soil and harm man and other living beings.

Question 7. Explain how soil pollution is caused due to use of pesticides.
Answer:

Excessive use of pesticides causes soil pollution in farmlands in the following ways-

1. Pesticides and herbicides are a type of poison which are not decomposed by bacteria. As a result, they accumulate in the soil causing soil pollution.
2. The poisonous chemicals present in pesticides mix with the soil when sprayed on agricultural fields. The agricultural runoff flows into the waterbodies, causing further water pollution.
3. Excessive use of pesticides also kills other soil organisms.
4. The harmful effects of pesticides are also observed in human beings. Human beings ingest these toxic elements through the consumption of contaminated vegetables. Accumulation of these poisonous components in the body weakens the nervous system. As a result, lung diseases and stomach infections are common. It can even lead to cancer.

Question 8. How does inorganic manure cause soil pollution?
Answer:

Inorganic manure cause soil pollution:

if the inorganic manure or fertilizers are used in greater quantity it brings about soil pollution in the following ways-

1. If inorganic manure or fertilizers containing nitrogen is used excessively in agricultural grounds, it gets converted to poisonous nitrogen dioxide in the presence of sunlight, which in turn causes soil pollution.
2. Though this chemical increases soil productivity in the short run, in the long run, this chemical clogs the soil pores lowering the aeration and water-holding capacity of the soil.
3. Thus soil productivity decreases in the long run.
4. Excessive use of phosphates to increase soil productivity also causes soil pollution as high levels of phosphate dissolved in the soil harm plant growth.

Question 9. What are the different types of soil pollutants?
Answer:

Different types of soil pollutants:

The substances which bring about soil pollution are called soil pollutants. The different types of pollutants and their origin are listed below-

Question 10. Fill up the knowledge hive with information about the Chernobyl disaster.

Answers:

1. A nuclear reactor exploded at Chernobyl in Ukraine at 1.30 am on 26 April 1986.
2. In this explosion radioactive materials. scattered over a region of about 3000 sq km.
3. In this explosion 31 persons had died and more than a million were severely affected.
4. The land on the periphery of the explosion zone became unsuitable for agriculture.
5. Farm animals as well as human beings gave birth to deformed progeny due to the effect of radioactivity.

Question 11.

 

Down:

1. Soil pollutant
3. A ferroalloy

Across:

2. A vegetation cover that controls soil erosion and promotes soil fertility
4. Chemical sprayed on farmlands to kill pests.
5. The gas which leaked in the Bhopal Disaster

Answers:

Down: 1. PLASTIC, 3. ARSENIC
Across: 2. GRASSLAND 4. PESTICIDE 5. MIC

Question 12.

 

Down:

1. An inorganic pollutant.
2. Organic matter whose presence turns the color of the soil black
3. A gas emitted through the decomposition of soil organisms.

Across:

4. A heavy metal
5. A chemical fertilizer

Answers:

Down: 1. PHOSPHATE, 2. HUMUS, 3. METHANE
Across: 4. CADMIUM, 5. UREA

WBBSE Chapter 8 Soil Pollution Short Question And Answers

Question 1. How does industrialization cause soil pollution?
Answer:

Industrialization cause soil pollution:

• Industrial centers are the major sources of chemicals that cause soil pollution. The wastewater that is discharged from various industrial activities contains a lot of chemicals, radioactive materials, metallic wastes, and many other insoluble materials.
• Besides, different gaseous and non-gaseous wastes are let out from factories and mixed with the soil causing soil pollution.

For example- Fly ash from thermal power stations mixes with the soil reducing its fertility.

Question 2. Describe how inorganic wastes cause soil pollution.
Answer:

Inorganic wastes cause soil pollution:

• Poisonous metals generated from different metal-based industries example, lead, copper, mercury, nickel, cadmium, and waste products from towns and cities example, plastic, gas, storage battery, and chemical fertilizers usually accumulate in the soil.
• The organisms present in the soil absorb these toxic compounds and degenerate the soil quality. This is known as pollution by inorganic wastes.

Question 3. How does urbanization cause soil pollution?
Answer:

Urbanization cause soil pollution:

High rate of population growth has increased the pace of urbanization.

• It has resulted in an increase in the requirement of land for dwelling, agricultural activities, industrial activities, construction areas, etc.
• These have led to an increase in the following factors-construction of brick kilns, landfill, and illegal dumping, throwing of domestic garbage anywhere, improper disposal of municipal and industrial wastes.
• As a result of these soil is getting eroded as well as polluted.

Question 4. How do agricultural activities cause soil pollution?

Agricultural activitAnswer:ies cause soil pollution in the following ways-

•  Use of pesticides: To increase the productivity of crops, spraying of pesticides is very common. This kills the beneficial microorganisms and other organisms present in the soil. As a result, the soil loses its productivity.
• Use of chemical fertilizers: To increase agricultural productivity, chemical fertilizers are sprayed on fields. This alters the organic composition of the soil, increasing its salt content. As a result, the soil becomes unproductive.
• Excessive ploughing: Excessive ploughing on agricultural fields erodes the top layer of the soil, resulting in the removal of the nutrients contained in it

Question 5. Write a short note on the effects of soil pollution.
Answer:

The effects of soil pollution are-

1. Loss of fertility and productivity of the soil.
2. Changes in the physical and chemical characteristics of the soil.
3. Lowering of the protein content of various crops.
4. Affected plant growth and animal health.
5. Affected crop cultivation and human health.
6. Groundwater pollution.
7. Imbalance in the natural ecosystem.

Question 6. What is the impact of acid rain on the soil?
Answer:

Impact of acid rain on the soil:

Acid rain falling on the Earth’s surface adversely affects the soil. The major effects of acid rainwater mixed with the soil are as follows:

1. The soil becomes acidic.
2. The flora cannot perform photosynthesis, leading to the growth of distorted branches and stems.
3. This affects the normal growth and development of plants.
4. The soil loses its fertility making it unsuitable for cultivation.
5. Death of the microorganisms that are present in the soil is one of the harmful impacts of acid rain.

Question 7. Write a brief note on Bhopal Gas Tragedy.
Answer:

Bhopal Gas Tragedy:

• The Bhopal Gas Tragedy was a toxic gas leak incident in India that occurred on the night of 2-3 December 1984 from the pesticide plant of Union Carbide India Limited in Bhopal, Madhya Pradesh.
• The local people were exposed to about 36 tonnes of toxic methyl isocyanate or MIC gas and other chemicals. This gas affects the human lungs and burns the cornea of the eyes.
• The Bhopal Disaster brought about the death of around 10,000 people (unofficial count) approximately and disabled or injured another 2 lakh people.

Question 8. Write a short note on Chornobyl Disaster.
Answer:

Chornobyl Disaster:

• The Chornobyl Disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chornobyl Nuclear Power Plant in Ukraine.
• An explosion and fire released a large quantity of radioactive particles into the atmosphere, which spread over a wide area. About 1 lakh 35 thousand people were evacuated as a result of this disaster.
• According to scientists, the impact of this disaster will be felt for another 100 years.

Question 9. What are the things one should do to avoid soil pollution in villages?
Answer:

‘Things to do’ in villages to avoid soil pollution are as follows-

1. Farmers should be explained why excessive use of chemical fertilizers in farmlands is not advisable and their harmful effects on human health.
2. The farmers should be made aware about the advantages of organic farming.
3. The farmers should be told about the negative effects of pesticides.
4. The farmers should be explained the advantages of controlled growth of organisms in comparison to the use of pesticides.
5. Farmers should be made aware about the high water retention capacity. This soil is ideal negative effects of mono-cropping.
6. Information and advice should be given to the farmers about the general improvement of their farm produce.
7. The people should be made aware of the inter-relationship between the environment and farming.

Question 10. What is the importance of soil?
Answer:

Importance of soil:

The importance of soil is limitless. A few of them are as follows-

1. Soil provides water, minerals, and nutrients which help organisms to survive.
2. Plants grow in soil.
3. The soil acts as the safest habitat for bacteria, fungi, algae, rats, worms, etc.
4. A variety of crops grow in a variety of soil. For example, cotton grows in black regur soil, wheat grows in chernozem soil.
5. The brick kilns and clay industry are highly dependent on soil.

Question 11. Huge amounts of paddy, jute, and vegetables are grown in the silt soil on the banks of the Ganga. But less amount of crops grows in the coarse soil of Purulia. Why?
Answer:

The alluvial soil formed by silt deposited by River Ganga is fine-grained, fertile, and has for crop cultivation because the movement of air within the soil particles is good.

• On the other hand, the soil in Purulia is coarse, infertile, and full of pebbles.
• It contains very less organic matter and has a low water-retention capacity.
• Therefore, crops do not grow in abundance in the soil of Purulia.

Question 12. Beautiful flowers bloom every day in the plants of your flower pots or garden. What may happen to the plant if filthy oil is poured into the pot?
Answer:

Beautiful flowers bloom every day in the plants of your flower pots or garden.

If filthy oil is poured into the flowerpots, it will degrade the soil quality. The plant will not be able to obtain the necessary nutrients from the soil and after a few days it will die, because-

1. Plant roots will not be able to take in water from the soil.
2. The level of nutrients present in the soil will decrease.
3. The movement of air within the soil will decrease.

Question 13. What do you mean by soil pollution?
Answer:

Soil pollution:

• Any process that degrades the quality of soil and reduces its productivity and utility is called soil pollution.
• Harmful chemicals from agricultural run-offs due to overuse of chemical fertilizers and pesticides, weedicides, plastic, domestic wastes, industrial wastes, biodegradable and non-biodegradable substances, and radioactive waste products mix with the soil.
• Thereby altering its properties or characteristics and nutrient content.

Question 14. How do the microorganisms cause soil pollution?
Answer:

Microorganisms cause soil pollution:

• Waste products of households, markets, and hospitals are usually not disposed of properly.
• This garbage acts as the breeding ground of different viruses and bacteria which affect the soil quality and the organisms present in it. The soil becomes unproductive.

Question 15. Write how radioactive pollutants cause soil pollution.
Answer:

Radioactive pollutants cause soil pollution:

• Radiation from nuclear reactors, medical imaging, and scientific research processes emit radioactive substances or particles.
• These emitted particles mix with the soil causing soil pollution. The main radioactive pollutants are- Carbon 13, Uranium-235, Radium-226, etc.

Question 16. How is soil pollution caused by soil erosion?
Answer:

Soil pollution caused by soil erosion:

• Removal of the fertile topmost layer of the soil which contains organic matter or humus due to the action of natural agents like rain, running water, wind, and glacier is called soil erosion.
• As the uppermost layer is removed the soil loses its fertility and becomes unsuitable for plant growth. Thus, soil erosion is a natural factor causing soil pollution.
• Among the pesticides used in agricultural fields, the chemicals which cause maximum soil pollution are Dichloro Diphenyl Trichloroethane (DDT), Benzene Hexachloride (BHC), Pyrethrin, Malathion, and compounds containing carbonate.
• The main chemical fertilizers causing soil pollution are urea, phosphate, and sulfate compounds.

Question 17. What are the diseases caused in humans as a result of soil pollution?
Answer:

Many diseases and their symptoms are observed in humans as a result of soil pollution.

These are as follows-

Question 18. Name the type of diseases which occur in human bodies due to the use of pesticides.
Answer:

• Pesticides enter the human body through the consumption of fruits and vegetables.
• The high amount of accumulated pesticides in the human body weakens the nervous system resulting in lung diseases and stomach infections and may often lead to cancer.

Question 19. What are the causes of the increase in the level of acidity of the soil?
Answer:

The causes of the increase in the acidity level of soil are as follows-

• In forest areas, the dead leaves fall on the forest floor, get decomposed, and form humus. This humus releases humic acid which increases the acidity of the soil.
• Presently eucalyptus trees have been planted in various forest areas to curb the effect of deforestation. The acidity level of the eucalyptus leaves is high. The leaves that fall on the forest floor mix with the soil turning it acidic.
• Nowadays, nitrogen-based fertilizers are used in abundance on the farmlands. This increases the acidity of the soil.
• Toxic wastes discharged from various industries are highly acidic in nature. These mix with the soil turning it acidic.

Question 20. How does the organic matter present in the soil cause soil pollution?
Answer:

The organic matter present in the soil cause soil pollution:

• When inorganic pesticides, like DDT and Chlorodon mix with the soil, the organisms present in the soil absorb these substances into their bodies.
• Gradually the poison released from the chemicals moves within the body of the organisms poisoning the organic matter of the soil. This is called soil pollution due to organic matter the soil.

Question 21. What are the causes for increased levels of salinity in the soil?
Answer:

The causes of the increase in the salinity level of the soil are-

1. Intensive irrigation on farmlands increases soil salinity.
2. Continuous irrigation on the same plot of land accumulates the soluble salts which then get stored in the soil increasing its salinity.

WBBSE Chapter 8 Soil Pollution Very Short Question And Answers

Question 1. Which term is used to denote the deterioration of soil quality?
Answer: Soil pollution.

Question 2. What are burnt ash from coal and coal particles emitted along with the smoke of factories and thermal power stations collectively called?
Answer: Fly ash.

Question 3. Name a non-degradable material which blocks the sewage drains of cities.
Answer: Plastic.

Question 4. Name one radioactive pollutant.
Answer: Uranium.

Question 5. Which type of rainfall increases soil acidity?
Answer: Acid rain.

Question 6. Which poisonous substance was responsible for Bhopal Gas Tragedy?
Answer: MIC gas (Methyl Isocyanate).

Question 7. Which disaster occurred in a nuclear power station in Ukraine in 1986?
Answer: Chornobyl disaster.

Question 8. Which type of farming does not cause soil pollution?
Answer: Organic farming.

Question 9. I am a process. My harmful effect degrades the quality of soil and reduces its productivity and utility. Who am I?
Answer: Soil pollution

Question 10. Cutting us down washes the soil during heavy rainfall. Who are we?
Answer: Plants and trees

Question 11. Our application increases crop productivity but excessive use causes soil pollution. Who are we?
Answer: Chemical fertilizers

Question 12. My application kills the disease-causing microbes and both useful and harmful insects present in the soil. Who am I?
Answer: Pesticide

Question 13. I am emitted from thermal power stations and on settling down on the soil, I cause soil pollution. Who am I?
Answer: Fly ash

Question 14. I mix with rainwater, thereby increasing the soil acidity. I kill or harm organisms present in soil. Who am I?
Answer: Acid rain

Question 15. We do not decompose easily, and restrict the entry of water by clogging the soil pores. Who are we?
Answer: Plastic, polythene

WBBSE Chapter 8 Soil Pollution Fill In The Blanks

Question 1. Particles of _______ and _______ mix with rainwater causing soil pollution.
Answer: Radium, iodine

Question 2. _______ emitted from thermal power plants mixes with the soil, degrading its fertility.
Answer: Fly ash

Question 3. The excreta of humans and animals are the main source of _______ soil pollution.
Answer: Organic

Question 4. The sewage system is badly affected by improper disposal of _______.
Answer: Plastic

Question 5. An important inorganic soil pollutant is _______.
Answer: Plastic

Question 6. An example of a living soil pollutant is _______.
Answer: Protozoa

Question 7. Bacteria is an example of _______ soil pollutant.
Answer: Living

Question 8. _______ is a type of heavy metal soil pollutant.
Answer: Cadmium

Question 9. Plastic is an example of _______ soil pollutant.
Answer: Inorganic

Question 10. An example of medical waste is _______.
Answer: X-ray plate

Question 11. High amounts of accumulated pesticides in human bodies cause diseases in _______ and _______.
Answer: Lungs, stomach

Question 12. Soils which have low organic matter are _______.
Answer: Infertile

Question 13. The gas responsible for the Bhopal Gas Tragedy is _______.
Answer: MIC

Question 14. The Chornobyl Disaster took place in _______.
Answer: Ukraine

Question 15. _______ Farming reduces agricultural soil
Answer: Organic

WBBSE Chapter 8 Soil Pollution True Or False

Question 1. Acid rain does not cause soil pollution.
Answer: False

Question 2. Dead remains of plants and animals present in the soil do not form humus.
Answer: False

Question 3. Plastic is an inorganic compound which cannot be decomposed.
Answer: True

Question 4. Industrial wastes are not found in the soil of the Asansol-Durgapur industrial belt.
Answer: False

Question 5. The major cause of soil pollution in urban areas is acid rain.
Answer: True

Question 6. The waste products of hospitals cause soil pollution.
Answer: True

Question 7. Plastic and polythene substances do not cause soil pollution when in contact with soil.
Answer: False

Question 8. The garbage disposal site in Kolkata is Dhapa dumping ground.
Answer: True

Question 9. To control soil pollution, decomposed substances should be buried under the soil.
Answer: True

Question 10. Bhopal Gas Tragedy happened in 1984.
Answer: True

WBBSE Chapter 8 Soil Pollution Find The Odd One Outs

Question 1. Increasing population Deforestation: Contamination of waterbodies: Landslide
Answer: Contamination of waterbodies (not related to soil erosion)

Question 2. Chernobyl : Fukushima: Hiroshima : Bhopal
Answer: Bhopal (not related to radioactive pollution)

Question 3. Posts: Polythene : Plastic: Artificial rubber
Answer: Pests (not related to soil pollution)

Question 4. Thermal power station: Brick-kiln ash: Radioactive wastes: Landslide
Answer: Landslides (not a man-made cause of soil pollution)

WBBSE Chapter 8 Soil Pollution Correct The Following

Question 1. Water becomes polluted if the same crop is planted again and again.
Answer: Soil

Question 2. Air gets polluted if the soil is dug to make bricks for the kiln.
Answer: Soil

Question 3. 90% of the world’s population live on 90% of the landmass on the Earth.
Answer: 10%

Question 4. Only part of the Earth is water.
Answer: Land

WBBSE Chapter 8 Soil Pollution Scrambled Words

1. SANIBAONURTI
2. ERBAIACT
3. TISCIPEDE
4. ERNOBCHYL
5. OACDIVIRATITY

Answers:

1. URBANISATION
2. BACTERIA
3. PESTICIDE
4. CHERNOBYL
5. RADIOACTIVITY

WBBSE Chapter 8 Soil Pollution Match The Columns

Question 1.

Answer: 1. D, 2. A, 3. B, 4. E, 5. C

Question 2.

Answer: 1. E, 2. C, 3. D, 4. B, 5. F, 6. A

Question 3.

Answer: 1. D, 2. E, 3. A, 4. F, 5. C, 6. B

WBBSE Chapter 7 Water Pollution Long Question And Answers

Question 1. Discuss the causes of water pollution.
Answer:

Causes of water pollution:

Water can be polluted in various ways-

1. Pollution due to industrial wastes:

Water pollution is caused by industrial wastes disposed from petrochemical, plastic, fuel industries, and oil refineries (like copper, lead, chromium, calcium, zinc, and other metals, organic and inorganic compounds. of sulfur, phosphorus, and chlorine).

2. Pollution due to domestic wastes:

Vegetable peels, leftover food, detergent, soap, human wastes, and insecticides enter the rivers and other sources of water through the house drains. Again organic and inorganic wastes from markets, clinics, and hospitals also pollute water.

Read And Learn Also WBBSE Solutions For Class 7 Geography

3. Pollution from agriculture:

The chemical fertilizers and pesticides used in agriculture and chemical substances like nitrate, phosphate, and potash produced by weeds pollute water.

The nitrates present in fertilizers hamper blood circulation in children’s brains and are also a known cause of cancer.

4. Pollution from mineral oil:

Tanker accidents in the sea, bursting of conducting pipes, and wastes produced by the combustion of engine oil in ships, steamers, and mechanized boats pollute the river and seawater.

5. Thermal pollution in water:

A lot of water is required for cooling the machine parts in atomic power plants, thermal power plants, and different industries. When this heated water falls in rivers or seas and on the ground it causes harmful ecological changes in water and endangers the existence of aquatic creatures.

Apart from this, water also gets polluted due to arsenic pollution and air pollution.

Question 2. Write down the causes of pollution in the Ganga.
Answer:

The causes of pollution in the Ganga:

Polluted water from different sources mixes with the water of the river Ganga. The causes of pollution in river Ganga are-

1. Discharge of urban solid and liquid waste:

Often solid and liquid waste materials are discharged in Ganga from the cities located near the bank of river Ganga. These huge amounts of waste substances disposed from the cities located on the banks of river Ganga pollute the water.

2. Disposal of industrial waste:

The unrefined waste substances produced by the numerous industries which are situated on both sides of the banks of river Ganga are disposed in the river water making it unsuitable for drinking and for the survival of marine animals.

3. Washed away the water of fertilizers and pesticides:

Chemical fertilizers and pesticides used in the agricultural lands on the bank of river Ganga are washed away by rainwater to the river making the water polluted.

4. Pollution caused by shipping:

The large vessels, ships, and steamers that are used as modes of transport in river Ganga, sometimes throw burnt oil, grease, etc. into the water of Ganga which mixes with it and makes the river water polluted.

5. Other causes:

Idols, flowers used in pujas, household wastes, etc. are disposed of in Ganga. This is gradually increasing the pollution in river Ganga.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 3.  Discuss the effects of water pollution.
Answer:

Effects of water pollution:

The effects of water pollution are as follows-

1. Effect on human health:

1. Arsenic pollution can cause cancer of the lungs, liver, kidney, bladder, and skin.
2. Black patches develop on the palms and soles as a result of arsenic reactions. This is called Blackfoot disease.
3. Diseases like viral hepatitis, polio, cholera, and dysentery are caused by water pollution.
4. IQ of children decreases due to lead pollution.

2. Effect on agriculture:

If contaminated water is used on agricultural lands, then the beneficial bacteria, virus, and other micro-organisms are killed and this affects the crops adversely. Again the presence of various heavy metals can also be detected in the produced crops.

3. Effect on the sea:

• If the seawater gets polluted then it greatly harms the aquatic plants and animals as well as the entire ecosystem. For instance, the ecosystem around the Minamata Gulf was greatly harmed by mercury pollution.
• Some compounds also destroy the taste and color of fish.

4. Effect on birds:

If polluted water seeps into the sea then it becomes quite harmful for fish and the birds dependent on those fish. For instance, more than a million birds were killed during the Gulf War.

Question 4. What are the essential measures of controlling water pollution?
Answer:

Essential measures of controlling water pollution:

The following measures are to be adopted to control and prevent the harmful effect of water pollution-

1. Industrial effluents should be properly treated and neutralized in a scientific way before being discharged in the river.
2. Domestic waste and sewage should be discharged into waterbodies only after treatment.
3. Oil tankers should take careful measures to avoid oil spills.
4. Waterbodies should be cleared of water hyacinths, algae, mosses, etc. Weeds and other unwanted plants must be removed from the banks before every rainy season.
5. The waterbodies used for drinking purposes should not be used for washing clothes, bathing of humans and animals, etc.
6. The use of chemical fertilizers and pesticides in agricultural fields should be reduced.
7. Awareness regarding the harmful effects of polluted water should be spread among the common people.

Understanding Water Pollution

Question 5. What can be done to conserve water and control water pollution?
Answer:

Ways to conserve water and control water pollution:

Water is very essential for living organisms. So to conserve water and control water pollution, the society needs to play a significant role. There are many ways to conserve water and control water pollution-

1. Avoiding misuse of water:

If not required the water tap should be closed. In this way pure water will not be wasted and water pollution will also decrease.

2. Use of harmless soap and shampoo:

Less alkaline soap, shampoo, detergent, etc. should be used which will not harm the environment and control the pollution of water.

3. Disposal of waste in a particular place:

House waste, liquid waste, etc. should be disposed off in such a place so that it would not mix with pure water.

4. Planting trees:

Vegetable plants and plants bearing fruits and flowers should be planted in gardens, banks of ponds, around wells, and tube wells. In this way polluted water can be treated and soil erosion can be prevented.

5. Reusing water:

Water should be recycled and reused in many ways.

6. Increasing social awareness:

People can be made aware of water conservation and control of water pollution through seminars, posters, essay-writing competitions, etc.

Apart from this, in low cost, knowledge can be imparted to people about water purification and different ways of water conservation.

Question 6. What are the major water reserves on Earth?
Answer:

The major water reserves on Earth:

Three-fourths of the Earth’s surface is covered with water. Out of the total water on the Earth’s surface, 97% is ocean water of the seven oceans on Earth. The Pacific Ocean is the largest and has the maximum volume of water.

Of the three parts of freshwater, two parts are stored as glaciers and ice caps; the remaining one part of freshwater includes the water in rivers, ponds, lakes, and groundwater.

Question 7. What are the sources or causes of water pollution in villages?
Answer:

The causes of water pollution in villages are-

1. In the villages, humans and animals like cattle together bathe in ponds and other smaller waterbodies. Again, in that same water, utensils, and clothes are also washed. This makes the water very polluted.
2. Many villagers excrete water very polluted. on the banks of the water bodies thus leading to more water pollution.
3. Nowadays, chemical fertilizers, insecticides, and pesticides are used extensively to raise crops and improve soil productivity of farmlands in villages. These are washed away by rainwater to the waterbodies, thus causing water pollution.

Question 8. What are the sources or causes of water pollution in urban areas?
Answer:

The causes of water pollution in urban areas are-

1. There are many industries in the urban areas. Industrial activities create a wide variety of waste products which are discharged into the waterbodies, causing contamination of water.
2. In urban areas, soaps and detergents are very widely used. These substances get discharged in the river bodies through the sewage system and cause water pollution.
3. Household waste, domestic wastewater, municipal waste or sewage are also carried to the river through drains and this, pollutes the rivers.

Question 9. How do heavy metals pollute water?
Answer:

Heavy metals pollute water:

• Runoff from mines with high concentrations of chemicals, by-products from smelting plants, and lead emissions from vehicles cause water pollution.
• These poisonous metals enter the food chain and thus are found in increasing proportion in human beings. An increased proportion of these poisonous metals in organisms can even cause death.
• Some of the heavy metals causing a threat to human health are lead, mercury, cadmium, zinc, tin, manganese, cobalt, arsenic, and so on.

Question 10. How does domestic waste cause water pollution?
Answer:

Domestic wastewater contains paper, polybags, plastic articles, cloth, soap, excreta, vegetable waste, etc. Polluted water from restaurants mixes with the water of ponds, water- bodies, rivers, and so on, causing water pollution.

This may cause water pollution in three ways-

1. Eutrophication,
2. Biological oxygen demand and
3. Inorganic non-biodegradable waste.

Question 11. How do pesticides cause water pollution?
Answer:

• Excessive use of pesticides, insecticides, and weedicides is common in farms practicing mixed farming, high-yielding paddy cultivation, and farming using modern techniques.
• The run-off from these chemically-treated fields flows into nearby waterbodies thereby causing water pollution.
• This type of water pollution is called water pollution due to the use of pesticides.
• The main pesticides used are D.D.T. gamaxene, endrin, folidol, etc.

Question 12. How do radioactive wastes cause water pollution?
Answer:

• Radioactive elements like uranium, thorium, radium, etc. spontaneously disintegrate in a short period, thus emitting electromagnetic radiations like alpha and beta particles and gamma rays, which are very harmful to living organisms.
• This is called radioactive pollution. Radioactive elements are used in various nuclear reactors and scientific research. The radioactive wastes are dumped into rivers, seas, and oceans after use which causes water pollution.

Question 13. What do you mean by thermal pollution of water?
Answer:

There are two main sources of thermal pollution.

They are-

1. Machineries of different industries are immersed in water to cool which in turn makes the water warm.
2. Warm water comes out from thermal power plants and atomic power stations.

This warm water is discharged into rivers and other waterbodies causing thermal pollution of water. Various aquatic organisms like fish die and aquatic flora is destroyed.

Question 14. What is arsenic pollution?
Answer:

Arsenic pollution:

• Unlimited extraction of groundwater from wells and tubewells results in void space within the layers.
• Air enters these void spaces and reacts with the arsenic element of the bedrock forming poisonous arsenic compounds.
• This dissolves in the groundwater causing a kind of water pollution called arsenic pollution.
• A high level of arsenic contamination has been found in the districts of West Bengal located to the east of River Ganga.
• According to the Bureau of Indian Standards, the permissible level of arsenic in drinking water is 0.01 mg/l.

Question 15. What causes arsenic pollution?
Answer:

The causes of arsenic pollution are-

1. Overuse of groundwater.
2. Excessive use of insecticide, pesticide, fungicide, etc.
3. Use of chemical fertilizers rich in ammonia, sulfates, and phosphates in high amounts.
4. Excessive use of fossil fuels.
5. Arsenic pollution may also occur while mining minerals like gold, copper, lead, etc., and in paints, soap, batteries, and medicine manufacturing industries.

Question 16. Explain fluoride pollution.
Answer:

Fluoride pollution:

Fluoride pollution is the pollution which is characterized by high levels of fluoride in water fluoride in each liter of water is considered as or air.

• Water containing more than 1mg of polluted water.
• Excessive intake of fluoride by humans for a long time causes a medical condition called fluorosis. It damages bones and teeth, causes skin irritation, affects the eyes, and lungs, and sometimes can damage the heart in humans.
• Excessive fluoride in the body can cause calcium deficiency in the body.

Question 17. What are the harmful effects of water pollution?
Answer:

Human beings as well as aquatic flora and fauna and soil are affected by water pollution in various ways such as-

1. Most of waterborne diseases like Typhoid, Cholera, Jaundice (Hepatitis), Amoebiasis, and Dysentery may spread through contaminated water.
2. Water contaminated with copper, mercury, sulfur extracts may cause various skin diseases in humans.
3. Water pollution removes various beneficial bacteria and other micro-organisms from the soil, thus lowering the fertility of the soil.
4. Toxic sea water depletes the population of both aquatic plants and animals, thus decreasing the population of fish as well.

Question 18. What are the effects of water pollution caused due to use of pesticides?
Answer:

The effects of water pollution caused due to use of pesticides:

Water pollution due to the use of pesticides has the following harmful effects on humans

1. Though harmful pests are killed by the use of pesticides, the indiscriminate use of pesticides leads to the growth of various other viruses and bacteria.
2. pH balance of water changes. Drinking water with a pH balance of less than 4 may be fatal.
3. Strong pesticides kill the aquatic flora and fauna thus disturbing the balance of the aquatic ecosystem.

Question 19. What is Minamata disease?
Answer:

Minamata disease:

Japan’s Chisso Corporation’s chemical factory released methylmercury in the industrial wastewater from 1932 to 1968 which flowed into the Minamata Bay.

This highly toxic chemical bio-accumulated in the shellfish and fish, which when eaten by the local population caused mercury poisoning. This came to be known as the Minamata disease. The symptoms of this disease are-

1. Numbness of hands and legs
2. Muscle weakness
3. Insanity
4. Paralysis.

About 2,265- people were affected by this disease and among them, about 1,784 people died.

Question 20. What happened due to oil spills in the Persian Gulf during the Gulf War of 1991?
Answer:

During the Gulf War of 1991, many oil wells of Iran and Kuwait were set on fire. Besides, a huge quantity of petroleum got mixed in the waters of the Persian Gulf. As a consequence, the ocean water was polluted and many marine organisms died.

Question 21. What are the different diseases caused due to heavy metal contamination of drinking water?
Answer:

The different diseases caused due to heavy metal contamination of drinking water are-

1. ‘Blackfoot’ disease as a result of arsenic pollution.
2. ‘Fluorosis’ disease as a result of fluoride pollution.
3. ‘Itai-itai’ disease as a result of cadmium pollution.
4. ‘Minamata’ disease as a result of mercury pollution.

Question 22. What are the effects of arsenic pollution?
Answer:

Prolonged drinking of arsenic-contaminated water has the following effects-

1. The skin becomes dull/pale.
2. Black spots or patches are seen on the soles of the feet, palms of hands, lower abdomen, neck, shoulders, chest, and back. This is called Blackfoot disease.
3. Difficulty in standing, walking, and carrying heavy things.
4. Severe pain in the limbs i.e., hands and feet.
5. Cancers of the bladder, kidney, and lung. Direct consumption of arsenic leads to nausea, vomiting, blood diarrhea, metallic taste in the mouth, extreme pain in the lower abdomen, and may also cause death.

Question 23. What is eutrophication?
Answer:

Eutrophication:

Surface run-off from agricultural fields contain inorganic compounds rich in nitrates, phosphates, and sulfates, which are carried to nearby ponds, lakes, rivers, etc.

As a result, the nutrient content of the water bodies increase, which promotes the excessive growth of phytoplanktons and algae. This phenomenon is called eutrophication. If this leads to the following-

1. As the number of aquatic plants increases, the Biological Oxygen Demand and the demand of oxygen of the aquatic plants increase.
2. The aquatic plants and animals ultimately die due to lack of oxygen.

Question 24. What are the effects of ocean pollution?
Answer:

The effects of ocean pollution are-

1. Due to oil spills in the bays and gulfs, many marine animals die,
2. Direct discharge from urban sewage and industrial waste in the form of toxic wastes causes marine pollution. For instance, after the construction of Haldia Petrochemicals in Haldia, the number of hilsa fish at the mouth of the Haldi River has greatly decreased.
3. Surface run-off (containing pesticides, insecticides, fertilizers, etc.) from agricultural fields causes marine pollution. For instance, a large number of fish have died in the Vembanad lagoon of Kerala, Chilka Lake of Odisha, and Kolleru Lake of Andhra Pradesh due to runoff.

Question 25. How does eutrophication affect the aquatic ecosystem?
Answer:

The harmful effects of eutrophication on the aquatic ecosystem are because of their rapid population growth, the aquatic plants require more and more quantity of oxygen and cause depletion of dissolved oxygen, thereby threatening the survival of other forms of aquatic life.

Question 26. What are the different types of water-borne diseases?
Answer:

The different waterborne diseases caused by microbes are listed below-

 

Question 27. Write a short note on Cholera.
Answer:

Cholera:

Type: Cholera is a waterborne disease caused by bacteria.

Micro-organism: The bacteria causing cholera is called Vibrio cholera

Symptoms:

1. Watery diarrhea and frequent vomiting.
2. Dehydration, dry mouth, and persistent thirst.
3. Hands and legs become weak.

Question 28. Write briefly about Amoebiasis.
Answer:

Amoebiasis:

Type: Amoebiasis is a waterborne disease caused by protozoa.

Micro-organism: The micro-organism causing Amoebiasis is Entamoeba histolytica.

Symptoms:

1. In the first stage of amoebiasis indigestion, acidity, and stomach infection is noticed.
2. Mucus with stool.
3. Abdominal pain and blood in the stool.

Question 29. What is dysentery?
Answer:

Dysentery:

Type: Dysentery is a waterborne disease caused by bacteria.

Micro-organism: The bacteria causing dysentery is known as Shigella dysentery.

Symptoms:

1. Abdominal pain, vomiting, stomach infection, etc.
2. Fever.
3. Severe watery diarrhea accompanied by blood and mucus in stool.

Question 30. Describe Hepatitis.
Answer:

Type: Hepatitis is a type of waterborne disease caused by a virus.

Micro-organism: This waterborne disease is caused by the Hepatitis virus.

Symptoms:

1. Nausea and poor appetite.
2. Abdominal pain at times.
3. Deep yellow urine.
4. The patient gradually becomes weak.

Question 31. Write a short note on typhoid.
Answer:

Type: Typhoid is a type of waterborne disease caused by bacteria.

Micro-organism: The name of the bacteria causing typhoid is Salmonella typhi.

Symptoms:

The symptoms of this disease are –

1. Stomach infections, vomiting, and abdominal pain are common.
2. High temperature ranging between 104°F to 105°F persists for a long time.
3. Headache and general weakness is observed.

Question 32. What measures can be taken to control waterborne diseases?
Answer:

The following measures should be taken to control waterborne diseases-

1. Clean, pure, and safe drinking water is to be used.
2. Water from rivers, ponds, and wells should be used for drinking only after purification.
3. Hands and face should be cleaned with soap every time before eating.
4. Consumption of cut fruits, ice, juice, coloured water in small packets sold on the roadside should be stopped.
5. Vaccines and immunizations for the different waterborne diseases will help control the spread of such diseases.

Question 33. What are the different processes of purifying drinking water?
Answer:

The various processes for purifying drinking water are-

1. Boil water at 100°C for about 10 minutes before drinking.
2. Adding an appropriate quantity of chlorine to kill micro-organisms in water.
3. Water is passed through charcoal, fine sand, and pebbles successively to get it purified.
4. If a thin plastic bottle filled with water is kept in the sun for 6-7 hours, then the same benefits of boiled water can be obtained.
5. Growing of water hyacinths helps to control the contamination of water as it absorbs many heavy metals and carcinogenic compounds present in water.
6. Adding small amounts of bleaching powder in water helps to kill the microbes in water.
7. Adding potassium permanganate in water also helps to kill harmful microbes in water.

Question 34. In what ways can the water that is unsuitable for drinking be changed into drinking water?
Answer:

The different ways by which water unsuitable for drinking can be changed into drinking water are-

1. By removing the color, smell, and taste of the water, if any.
2. By lowering the excess alkalinity of water.
3. By removing the dissolved iron and manganese salts.
4. By controlling the level of fluoride in water.
5. By desalinating the water, if required.
6. By mixing chlorine in the water.

Question 35. What measures can you take to prevent water pollution?
Answer:

Essential measures of controlling water pollution:

The following measures are to be adopted to control and prevent the harmful effect of water pollution-

1. Industrial effluents should be properly treated and neutralized in a scientific way before being discharged in the river.
2. Domestic waste and sewage should be discharged into waterbodies only after treatment.
3. Oil tankers should take careful measures to avoid oil spills.
4. Waterbodies should be cleared of water hyacinths, algae, mosses, etc. Weeds and other unwanted plants must be removed from the banks before every rainy season.
5. The waterbodies used for drinking purposes should not be used for washing clothes, bathing of humans and animals, etc.
6. The use of chemical fertilizers and pesticides in agricultural fields should be reduced.
7. Awareness regarding the harmful effects of polluted water should be spread among the common people.

Question 36. What measures should be adopted to control arsenic pollution?
Answer:

The measures to control arsenic pollution are-

1. The use of arsenic-rich pesticides and weedicides should be lessened.
2. Overuse of groundwater should be stopped.
3. Use of alum and bleaching powder to be practiced to control arsenic pollution.
4. Tubewells should be dug up to the correct depth and the level of arsenic in the water should be checked at regular intervals.
5. Consumption of boiled water should be practiced as it reduces the amount of arsenic in water.

Conceptual Questions on Government Policies for Water Protection

Question 37. What measures should be taken to control plastic pollution?
Answer:

To protect our environment from the harmful effects of plastics a number of measures should be taken.

They are

1. The law should be enforced to stop the manufacturing of plastic bags.
2. People should be made aware about the harmful effects of plastic.
3. The use of paper or jute bags should be increased instead of plastic bags.
4. Plastic bags or materials should not be thrown on roads or in waterbodies.

Question 38. How can fluoride pollution be controlled?
Answer:

Fluoride pollution can be controlled in the following manner-

1. Tubewell water that contains more fluoride than the permissible level should not be used for drinking.
2. The source of fluoride should be ascertained and general awareness about fluoride pollution should be spread among the people.

Question 39. Which areas of West Bengal are affected by arsenic pollution?
Answer:

The districts of the Ganga Delta region of West Bengal i.e., North 24 Parganas, South 24 Parganas, Nadia, Hugli, Howrah, Maldah, and Burdwan have reported cases of arsenic contamination in groundwater.

The reported values are much higher than that of the standard values prescribed by the World Health Organisation (WHO).

 

 

Arsenic polluted areas of West Bengal:

 

Source: Arsenic pollution in West Bengal by Dr. D. Elangovan and M.L. Chaklah.

Question 40. How does plastic pollution affect the environment?
Answer:

Plastic pollution affect the environment:

Plastic items are widely used in our daily lives. The use of plastic pollutes the environment in a number of ways-

1. Plastic items thrown on roads block the drains creating hindrances to proper sewage disposal. This results in the accumulation of water which is a breeding ground for mosquitoes.
2. Plastic items floating on waterbodies do not allow sunlight to enter the water bodies. As a result, aquatic plant and animal life perish, as the plants are unable to perform photosynthesis.
3. Accumulation of plastic items in rivers obstructs the flow of rivers. The water becomes stagnant and as a result, the organic matter in the water gets restricted in that area and with time rots, emitting a foul odor.

 

Question 41. Write about the water situation in your school or home.

1. From where do you get drinking water?
2. Have you ever noticed something turbid, foul odour in drinking water?
3. Do you use drinking water after purifying it in anyway?
4. Is anyone in your house, locality or class suffering from a stomach problem in the last three months?
5. Where is the household garbage disposed of?
6. Where does the sanitary water of your house drain into?
7. How much soap, shampoo, and detergent is used every month?
8. Are the ponds in your surroundings used for washing clothes or bathing cattle?
9. If there are cultivated lands nearby, find out how much chemical fertilizers are used throughout the whole year.
10. If there is any factory near your house or school, find out whether there is any provision for the purification of wastewater of the factory.

Answer:

Name: Prapti Basak

School: Jirat Colony High School Class: VII Sec: C Roll: 39

The subject of investigation: Inquiry about the conditions of water Date: 02-03-2022

1. Water from tubewell and supplied under the Sajal Dhara project.
2. In summer, I got filthy things in drinking water from the tubewell. But I did not see any turbidity or bad odour.
3. Yes, we put the drinking water in a container after boiling and cooling. We use clean water on the top of the container after removing the dust particles from the bottom of the container.
4. In the last three months, no one in my house and neighborhood has had stomach ailments, but a few of my classmates have not come to school for four days in the last week for stomach ailments.
5. In our neighborhood, household wastes are collected in certain dustbins.
6. The sanitary water of our house mixes with the septic tank.
7. 3 to 4 soaps and laundry soaps, 150 ml shampoo, and 1 kg of detergent are used every month.
8. Yes.
9. The amount of chemical fertilizers used per bigha is Urea-25 kg, Potash-17 kg, Gromor-20 kg, DAP-8 kg, and Sufala-8 kg.
10. There is no factory near my house, but a rice mill near my school. The waste materials emitted from it, are disposed of in a refinery adjacent to the mill.

Question 42. Now write how many people use pond water and for what purpose:

Answer:

Many people are dependent on pond water for their daily activities. Uses of pond water are-

1. Washing clothes,
2. Washing utensils,
3. Fishing,
4. Disposal of garbage,
5. Watering of trees,
6. Use as drinking water,
7. Disposal of materials,
8. Bathing of cows,
9. Pump irrigation,
10. Bathing and swimming.

Question 43. Observe and Survey:

1. If there is any lavatory within 10 meters of the tubewell and other sources of drinking water or if organic waste materials, urine, stool, garbage, or dead bodies are thrown.
2. Is there any confined water around the tubewell near your home?
3. Are the ropes, and buckets used in well and cleaned properly?
4. Is the water of the tubewell or well turbid or filthy?

Now you can write an essay on the basis of the information collected and read it out in front of the students of your class

Answer: A model answer is provided for the convenience of the students-

Name: Debarati Dutta

School: Somra Girls High School, Class: VII, Sec.: B, Roll: 24

The subject of Survey: Source of drinking water

Date: 12-03-2022

1. No, not thrown;
2. No, no water logging;
3. Yes, clean;
4. No, water is clean and pollution free.

An essay on the basis of the information collected.

I live in Somra in the Hooghly district. We all collect drinking water from deep tubewells and wells. There are no lavatories or dumping of organic wastes within 10 meters around the tubewells and wells used for water.

The tubewells and wells have been built high around them, so there is no confined water here and there. Buckets and ropes used in wells are cleared and replaced in a timely manner.

The mouths of the wells are covered with a wooden lid at times other than the time of watering. We make sure that water is not polluted. Hence, the water of tube-wells and wells is clean and pollution tree.

Question 44. If every one of your family is provided with at least twenty liters of pure water every day, then-

1. How would you use water and of what amount?
2. How much water would you save and in what way?
3. How much-used water would you reuse and how?

Answer: A model answer is provided for the convenience of the students-

1. Use of water:

 

2. Water storage:

Everybody will store water every day (20 liters – 18 liters) = 2 liters

3. Reuse of water:

Water used for bathing, washing clothes (approximately 6 liters) and for washing vegetables in cooking (approximately 2 liters) i.e. about (6+2)= 8 liters of water may be reused for watering the trees in the garden.

Question 45. You can submit the description of your experience to your school magazine after visiting any nearby water purification centre or water supply center.
Answer:

A sample is given for the convenience of the students

Name: Ankita Saha

School: Chandernagore Banga Vidyalaya, Class: VII, Sec: C, Roll: 9

The subject of Survey: Description of water supply center travel experience.

Date: 10-02-2022

I visited Tala, the main water supply center in Kolkata, last Sunday. I am writing my experience after visiting the Tala Tank and the information I gathered –

1. Construction of the tank began in August 1907 and was completed in November 1909 and was completed in November 1909 under the supervision of a British engineer. The tank is made entirely of steel.
2. The tank is built on 7 bighas of land. The height from the surface to the bottom of the tank is 110 feet and the depth of the tank is 16 feet.
3. The water holding capacity of the tank is 90 lakh gallons and according to the calculation of 1909, it cost Rs. 5 lakhs to build the tank. The Kolkata Municipal Corporation is responsible for its maintenance.
4. The tank does not have separate pipes for water storage and supply. When water from the Palta pumping station fills the groundwater tank at the bottom of the Tala tank, excess water accumulates in the tank. After the water supply, when the amount of water in the underground tank decreases, Tala refills the underground water tank with water.
5. In 2009, the 100th anniversary of this tank did not change the size of the tank, except for a few minor repairs. In the last 110 years, the tank has experienced Earthquakes and several cyclones, but no damage has been done to the tank.

Question 46. Which states of India are facing a water crisis?
Answer:

Though India is a country with abundant water reserves, inefficiency in the management and distribution of water supply has led to a water crisis in many states of India.

The states of India facing water crisis are-

1. Rajasthan,
2. Gujarat,
3. Uttar Pradesh,
4. Madhya Pradesh,
5. Chattisgarh,
6. Andhra Pradesh,
7. Tamil Nadu,
8. Maharashtra,
9. Telangana, etc.

 

Question 47. Fill in the hive concerning groundwater pollution

Answers:

1. The polluted water percolates through the surface of the Earth and contaminates the underground water.
2. Underground water also gets contaminated from septic tanks, dirty wells, oil wells, and garbage-clogged ponds.
3. The chemical underground pollutants are chlorides, nitrates, heavy metals, and toxic organic compounds. These compounds cause cancer.
4. The use of contaminated underground water affects the womb and causes underweight and other defects in newborn babies.
5. Nervous diseases may also occur.

Question 48. Fill in the hive concerning cadmium pollution.

Answers:

1. The Itai-Itai disease broke out among the people living in Jintsu (Jinzu) river valley of Japan due to cadmium pollution.
2. Cadmium is used to produce coloured plastic which returns to the environment as a waste product.
3. Cadmium also mixes with the soil from chemical fertilizers during the extraction of zinc from the ore.
4. Cadmium pollution makes the bones weak and brittle.
5. Cadmium pollution causes high blood pressure.

Question 49.

Down:

2. A water pollutant causing melanosis disease
3. Disease caused by Methyl Mercury contamination
4. Poison to kill pests

Across:

1. Phenomenon of increasing concentration of nutrients in the water
5. Disease caused by cadmium pollution

Answers:

Down:

2. ARSENIC,
3. MINAMATA,
4. PESTICIDE

Across:

1. EUTROPHICATION,
5. ITAI-ITAI

Question 50. Make an investigation

1. How many ponds are there in your village or locality?
2. Among them how many ponds are used daily?
3. What is the condition of the bank of the pond? (Constructed/Broken/Full of weeds) (iv) Are there trees and plants by the side of the ponds? What kind of trees?
4. Are there any worms, insects or small animals in the water of the ponds?
5. What is the condition of the water? (turbid water, reddish green or blackish water, decrease in the level of water, almost empty, full of water hyacinth and weeds, bad smell of water)
6. If water is polluted, what are the reasons for it? (Bathing of cattle/draining of water of sewage and lavatory into pond water/fertilizer from cultivation land, pesticides/waste oil of factories/dye chemical, high amount of detergent, soap, garbage from the household has been mixed with water)

Answer:

Name: Purbayan Dey

School: Dumurdaha Dhrubananda High School Class: VII Sec: A Roll: 33

The subject of Survey: Survey about the pond in our area

Date: 14-02-2022

1. There are seven ponds in my village
2. 4
3. Broken
4. Yes, there are trees like mango, coconut, betel nut, bamboo, etc.
5. Yes
6. The water level has decreased, in some places, water has even dried up.
7. Fertilizers, pesticides from farmlands.

WBBSE Chapter 7 Water Pollution Short Question And Answers

Question 1. What is water pollution?
Answer:

Water pollution:

• Water pollution is the contamination of water bodies with different chemical substances which results in a change in the physical and chemical properties of water and reduces the water quality and utility.
• It is very harmful to humans, animals, and water life (aquatic plants and animals).
• All the waterbodies of the Earth like the sea, ocean, river, lake, pond, and even the groundwater are affected by it.

Question 2. Name the chief water pollutants.
Answer:

The chief water pollutants are-

 

Question 3. What is the physical pollution of water?
Answer:

Physical pollution of water:

The quality of water changes when different types of polluted waste materials mix with water and it becomes unsuitable for human use. This is called physical pollution of water.

The effects of physical pollution of water are

1. Change in colour of water,
2. Turbidity of water change,
3.  Water becomes unsuitable for consumption.

On the whole, water becomes polluted.

Question 4. What is meant by water pollution of seas and oceans due to oil spills?
Answer:

Water pollution of seas and oceans due to oil spills:

1. Leakage from large vessels (ships and steamers) during transportation.
2. Sometimes burnt oil from ships is thrown into the oceans.
3. Tanker accidents in oceans cause large scale oil-spills.

Question 5. What are the effects of oil spills?
Answer:

Effects of oil spills:

• Oil spills result in the formation of a layer of oil on the surface of ocean water preventing the transfer of atmospheric oxygen into sea water.
• This causes breathing problems and even death of marine organisms.
• The oil layer blocks the entry of sunlight into the seawater. So the aquatic plants cannot perform photosynthesis and this causes the death of plants.

Question 6. What is Itai-Itai disease?
Answer:

Itai-Itai disease:

• Cadmium poisoning in humans causes severe pain in the spinal cord and joints. This is called Itai-Itai or Ouch-ouch disease. The disease first appeared around 1912 in Japan.
• The mining companies in the Toyama prefecture of Japan released significant quantities of cadmium and raised the pollution levels of the Jinzu River and its tributaries.
• As the water of this river, as well as that of its tributaries, was used for irrigation of rice fields, drinking, washing, fishing, etc. by the people, mass cadmium poisoning resulted.
• One of the main effects of cadmium poisoning is weak and brittle bones in humans.

Real-Life Scenarios Involving Water Quality Testing

Question 7. What is Blackfoot disease?
Answer:

Blackfoot disease:

Blackfoot disease is caused by arsenic poisoning. Dark black patches are seen on the palms of the hand and soles of the feet. So it is called Blackfoot disease.

The symptoms are-

1. Dark black patches on the soles
2. Paleness of the skin
3. Peeling of the skin of the hand

Question 8. What is arsenicosis?
Answer:

Arsenicosis:

Arsenicosis is a disease caused in humans as a result of excessive arsenic contamination. The symptoms of arsenicosis are-

1. Black patches on the palm of hands and soles of feet.
2. Black marks, spots, pimples, rashes on the body, skin irritation or even cancer may even occur.
3. Lung complications like asthma, bronchitis, etc are common.
4. Neurological disorders.

Question 9. What are inorganic biodegradable wastes?
Answer:

• Some materials like plastic cannot be degraded by any organism or bacteria. They remain disintegrated in waterbodies for years.
• As a result of this, the chemical constituents of these materials increase water pollution on one hand and on the other hand, reduce the depth of waterbodies.

Question 10. How do the drains get clogged?
Answer:

• Throwing plastic bags or plastic materials in open drains hinders the smooth flow of water.
• Gradually water accumulates at the mouth of the drains along with waste products, excreta, etc. This is called clogging of drains.

Question 11. At one time the pond near your house had sparkling clear water. People used to bathe and wash clothes in that water. But now it is filled with garbage, algae, and water hyacinth. Dead fish are seen floating in the water. Give reasons.
Answer:

• Washing clothes with detergent leads to the accumulation of a phosphate-based chemical in water resulting in the growth of algae, water hyacinth, etc.
• This is called eutrophication. This decreases the depth of the water. The domestic waste products thrown in the water lead to an increase in micro-organisms in the water.
• Due to the increased demand of oxygen by these microorganisms, the level of oxygen in pond water decreases. Due to oxygen deficiency, fishes die and float on the water’s surface.

Question 12. What measures can be taken to control water crisis?
Answer:

The measures which can be taken to control the problem of water crisis are-

1. Tanks should be constructed at various places to store rainwater.
2. Polluted water should be treated and made suitable for reuse.
3. The unnecessary use of water should be stopped.
4. Sewage systems and water supply systems should be improved.

Question 13. Mention the causes of water shortage in India.
Answer:

The causes of water shortage in our country are-

1. Unwise extraction of groundwater is taking place every day through shallow and deep tube-wells. As a result, the groundwater reserves are decreasing.
2. Indiscriminate use of water from ponds, lakes, etc. is decreasing the water reserves of these freshwater bodies.
3. Pollution in the agricultural field and industrial areas is making the freshwater bodies polluted and unsuitable for use.
4. Environmental pollution has created an imbalance in the water cycle of the Earth. This is leading to a decrease in rainfall amount.

Question 14. What role does acid rain play in water pollution?
Answer:

Acid rain plays role in water pollution:

• Any form of precipitation (rain, snow, sleet, hail) mixed with sulphuric, nitric, and carbonic acid released in the atmosphere forms acid rain.
• Acid rain has harmful effects on human life when acid gets deposited in rivers, ponds, seas, and oceans. Acid rain makes the water acidic and as a result, aquatic fish, insects, and algae die.
• In short, this causes an imbalance in the aquatic ecosystem. Thus, we can say that acid rain is one of the main reasons for water pollution.

Question 15. What is hypothermia? What is the relation between hypothermia in birds and oil spills?
Answer:

Hypothermia:

• Hypothermia is a condition where the core temperature of any living being fallen below that temperature which is required for normal metabolism and for carrying out functions.
• Oil spills in seas and oceans cause oil slicks- a layer of petroleum on the surface of the water. This petroleum sticks to the feathers and wings of sea birds and then the birds become incapable of flying.
• The feathers lose their water-proof quality. So, when the birds come in contact with water, their body temperature falls below normal and ultimately causes their death. This death of sea birds because of hypothermia usually results from oil spills.

Examples of Real-Life Applications of Water Pollution Knowledge

Question 16. Which industries are responsible for polluting the rivers of India?
Answer:

Name of some industries that are responsible for polluting the rivers are given in the following table-

 

Question 17. What does BOD mean?
Answer:

BOD:

Eutrophication leads to excessive growth of algae, mosses, and other aquatic flora in the water bodies.

As they die, the quantity of oxygen required by micro-organisms like bacteria increases because of the degradation of these dead aquatic plants. This is called BOD (Biological Oxygen Demand).

It is expressed in milligrams per liter of water. We can determine the quality of water through BOD. Example-

1. BOD-1-very good quality water
2. BOD-3-moderately clean water
3. BOD-10-polluted water
4. BOD-20-very polluted water

Question 18. What is dyslexia?
Answer:

Dyslexia:

Dyslexia is a disease that may be caused by lead contamination. Lead enters the human body through food and water primarily due to soil pollution. This causes poisoning in human bodies.

The effects of dyslexia are-

1. Neurological disorders
2. Learning disability in children
3. Respiratory problems

Important Definitions Related to Water Pollution

Question 19. What is ORS?
Answer:

ORS:

• The full form of ORS is an Oral Rehydration Solution. This is made by mixing water, sugar, and salt. Pharmacies sell ORS as a category of medicine containing important salts of sodium and potassium.
• When severe diarrhea, dysentery or continuous vomiting occurs, large amounts of water and minerals are lost from the body. Then patients are advised to consume ORS.

WBBSE Chapter 7 Water Pollution Very Short Question And Answers

Question 1. What percentage of the total water on the Earth’s surface is fresh water?
Answer: 3%.

Question 2. What is the reduction in the quality of water known as?
Answer: Water pollution.

Question 3. What are metals (including heavy metal) and metal compounds that negatively affect people’s health collectively called?
Answer: Toxic metals.

Question 4. Name one radioactive water pollutant.
Answer: Ash from the nuclear power plant.

Question 5. What is water pollution caused by hot water discharged from thermal power plants called?
Answer: Thermal pollution.

Question 6. What is the increased growth of algae and plankton in water bodies due to the effects of soaps and detergents termed as?
Answer: Eutrophication.

Question 7. Which disease causes black spots on the human body?
Answer: Melanosis.

Question 8. Which disease causes black patches on the soles of feet?
Answer: Blackfoot disease.

Question 9. Name a disease caused by mercury pollution.
Answer: Minamata.

Question 10. Name a disease caused in humans by arsenic pollution.
Answer: Arsenicosis.

Question 11. Name a disease caused in humans by fluoride poisoning.
Answer: Fluorosis.

Question 12. Name a waterborne disease caused by protozoa.
Answer:  Amoebiasis.

Question 13. Name a district of West Bengal affected by arsenic poisoning.
Answer: Nadia/Malda.

Question 14. What is the permissible level of arsenic in drinking water?
Answer: 0.01 milligram/liter.

Question 15. Which chemical is used to kill microbes in water?
Answer: Bleaching powder.

Question 16. What is the hindrance of normal water flow due to the presence of plastic in drains called?
Answer: Clogging.

Question 17. Name some plants which separate sediments from water.
Answer: Pea, Pulses.

Question 18. Which term is used to denote the quantity of oxygen required by microorganisms in water from the degradation of organic matter?
Answer: Biological Oxygen Demand.

Question 19. What is the accumulation of poisonous chemical substances in organisms known as?
Answer: Bio-accumulation.

Question 20. What is the principal cause of the water crisis?
Answer: Excessive extraction of groundwater.

Question 21. What is the primary reason for the water crisis globally?
Answer: Excessive use of water.

Question 22. Name a state from our country which has an acute water crisis.
Answer: Rajasthan.

Question 23. According to the UN, how much water per day is needed for a human being?
Answer: 20 liters.

Question 24. Which country reuses used water for irrigation?
Answer: Israel.

Question 25. What are the materials like plastic which cannot be decomposed by bacteria called?
Answer: Non-biodegradable waste substances.

Question 26. Do you think the fish in your aquarium will survive if phenyl or kerosene is poured into it?
Answer:

No, the fish will not survive. The application of phenyl and kerosene in the water of the aquarium will kill the fish because of their poisonous effect.

Question 27. I am a process through which the amount of algae in waterbodies increases and gradually the waterbodies get depleted. Who am I?
Answer: Eutrophication

Question 28. I am a metalloid causing the Blackfoot disease. Who am I?
Answer: Arsenic

Question 29. I am a microbe causing cholera. Who am I?
Answer: Vibrio cholerae

Question 30. I am a chemical which purifies water. Who am I?
Answer: Chlorine

Question 31. I am the chemical that causes the Fluorosis disease. Who am I?
Answer: Fluoride

Question 32. I am the metal that causes ‘Itai-Itai’ disease. Who am I?
Answer: Cadmium

Question 33. I am the metal that causes Minamata disease. Who am I?
Answer: Mercury

Question 34. I am a process by which the number of organisms in the water and the oxygen demand of the water body increases. Who am I?
Answer: Eutrophication

Question 35. We are such types of power stations which cause thermal pollution of water. Who are we?
Answer: Thermal power

Question 36. If the level of my presence in drinking water becomes more than 0.01 milligram/liter, it harms human life. Who am I?
Answer: Arsenic

WBBSE Chapter 7 Water Pollution Fill In The Blanks

Question 1. ________ poisoning causes Minamata disease.
Answer: Mercury

Question 2. ________ poisoning causes Ouch Ouch or Itai-itai disease.
Answer: Cadmium

Question 3. Eutrophication is a type of ________ pollution.
Answer: Water

Question 4. Arsenic is a type of ________.
Answer: Metalloid

Question 5. The disease caused due to fluoride contamination is ________.
Answer: Fluorosis

Question 6. The ________ disease is caused due to arsenic contamination.
Answer: Blackfoot

Question 7. Due to eutrophication, organisms like ________ grow profusely.
Answer: Algae

Question 8. Due to eutrophication, nutrients like ________ increase in water.
Answer: phosphate

Question 9. Hepatitis disease is caused by ________.
Answer: Virus

Question 10. Typhoid is a ________ disease.
Answer: Waterborne

Question 11. Due to water pollution, the number of fishes in oceans and seas ________.
Answer: Decreases

Question 12. Pollution by ________ causes fluorosis.
Answer: Fluoride

Question 13. Increased volume of ________ in drinking water causes brown stains on teeth.
Answer: Iron

Question 14. Arsenic concentration in drinking water has been observed in ________ region of United States of America.
Answer: Nevada

Question 15. According to the Bureau of Indian Standards, the permissible level of arsenic per liter of drinking water is ________.
Answer: 0.01 milligram

Question 16. Approximately ________ of the weight of an adult human constitutes of water.
Answer: 50-60%

Question 17. The skin becomes ________ when a person is infected with jaundice.
Answer: Yellow

Question 18. Cholera is a ________-borne disease.
Answer: Water

Question 19. About ________ percent of the water on the Earth’s surface is saline.
Answer: 97

Question 20. Mercury pollution in Minamata Bay happened in the year ________.
Answer: 1932

Question 21. Due to the excessive use of pesticides, ________ lake in Odisha has been largely polluted.
Answer: Chilka

Question 22. Boiling the water for ________ minutes at 100°C destroys all bacteria.
Answer: 10

Question 23. In Israel, 30% of used water is reused is ________.
Answer: Irrigation

WBBSE Chapter 7 Water Pollution True Or False

Question 1. Cadmium is a water pollutant.
Answer: True

Question 2. Dysentery is a waterborne disease caused by a virus.
Answer: False

Question 3. The enamel of our teeth decays due to the contamination of arsenic.
Answer: False

Question 4. Fluoride is an element.
Answer: False

Question 5. Arsenic poisoning has been detected in some districts of West Bengal.
Answer: True

Question 6. A person infected with typhoid has a fever for a long span of time.
Answer: True

Question 7. Itai-Itai disease is caused by mercury contamination.
Answer: False

Question 8. The micro-organism that causes cholera is Vibrio cholerae.
Answer: True

Question 9. The maximum permissible level of arsenic in drinking water is 0.5 milligrams/liter.
Answer: False

Question 10. Arsenic is a metalloid.
Answer: True

Question 11. The effect of arsenic contamination has been observed in South 24 Parganas district of West Bengal.
Answer: True

Question 12. A high concentration of arsenic has been observed in the Gangetic Plain of West Bengal.
Answer: True

Question 13. Typhoid is a waterborne disease caused by bacteria.
Answer: True

Question 14. We should stop the reckless use of groundwater.
Answer: True

Question 15. Lake Baikal is a freshwater lake.
Answer: True

Question 16. ¾ parts of the Earth’s surface is covered with land and ¼ part is covered with water.
Answer: False

Question 17. SO₂ and NO₂ react with rainwater to form acid rain.
Answer: True

Question 18. Minamata disease was first observed in China.
Answer: False

Question 19. Chlorine can destroy bacteria in water.
Answer: True

Question 20. Sewage from the thermal plants should be directly thrown into the sea or river.
Answer: False

Question 21. You must use less alkaline soap to mitigate water pollution.
Answer: Tru

WBBSE Chapter 7 Water Pollution Find The Odd One Out

Question 1. Malda Ganga river: Tubewell: Arsenic
Answer: Ganga river

Question 2. Blackfoot: Fluorosis: Itai-Itai: Acid rain
Answer: Acid rain

Question 3. Japan Minamata Mercury infection: Eutrophication
Answer: Eutrophication

Question 4. Cholera: Acid rain: Jaundice: Typhoid
Answer: Acid rain

Question 5. Arsenic Fluoride Cadmium: Nitrate
Answer: Nitrate

WBBSE Chapter 7 Water Pollution Correct The Following

Question 1. Cadmium pollution causes black ulcers on hands and feet.
Answer: Arsenic

Question 2. Cholera is a disease caused by soil pollution.
Answer: Water

Question 3. About 95 percent of water on Earth is saline.
Answer: 97

Question 4. The environment on the coast of Minamata Gulf became polluted due to arsenic pollution.
Answer: Mercury

Question 5. Almost 10 million children all over the world die due to water pollution.
Answer: 30

Question 6. A certain quantity of detergent destroys the germs in water.
Answer: Chlorine

WBBSE Chapter 7 Water Pollution Scrambled Words

1. LUONWAPOTTILER
2. DISUUROXLPHDEI
3. CKDISEFOAASOTEBL
4. UOFLSROSI
5. CATRHIONEUTIOP

Answer:

1. WATER POLLUTION
2. SULPHUR DIOXIDE
3. BLACKFOOT DISEASE
4. FLUOROSIS
5. EUTROPHICATION

WBBSE Chapter 7 Water Pollution Match The Columns

Question 1.

Answer: 1. D, 2. C, 3. E, 4. A, 5. B

Question 2.

Answer: 1. D, 2. E, 3. F, 4. B, 5. C, 6. A

Question 3.

Answer: 1. E, 2. C, 3. D, 4. F, 5. B, 6. A

 

WBBSE Chapter 6 Rock And Soil Topic B Soil Long Question And Answers

Question 1. How is soil formed from rocks?
Answer:

Soil formation from rocks:

Soil is formed from rocks by the following steps-

1. Effect of natural forces:

The heat from the sun, the impact of rain, wind, river water and other natural forces break down the rocks into smaller fragments.

2. Formation of regolith:

These small rock fragments settle down at the places of their origin. They also get carried away to far-off places due to transportation by water or wind.

This continuous degradation and transportation of the rock fragments lead to the formation of a layer of degraded and unconsolidated soil particles called regolith.

Read And Learn Also WBBSE Solutions For Class 7 Geography

3. Formation of soil:

Soil is derived from regolith by different organic and bio-chemical reactions. Regolith, due to these reactions, further disintegrates and stratifies to form soil.

Question 2. Discuss the factors that influence the formation of soil.
Answer:

Factors influencing the formation of soil:

There are four factors which influence the formation of soil. These are as follows-

Rock:

• The characteristic features of soil depend on the nature of the rock(s) from which it originates.
• The physical and chemical properties of the soil formed are influenced by the parent rock.

Example: Formation of black soil from basalt.

Climate:

• Rainfall and high temperatures facilitate soil formation.
• Soil forms at a faster rate in warm and rainy climates and at a slower rate in cool and dry climates.

 Relief:

• Relief of the land plays a vital role in the formation of soil. Gentler slopes, i.e., plain lands support better and deeper formation of soil.
• On the other hand, the formation of soil is less likely on steeper slopes.

Living organisms:

• Different living organisms, i.e., plants and animals, alive or dead have a great impact on the formation of soil.
• Ants, moles, earthworms and snakes loosen the soil which in turn allows free movement of water and air in the soil.
• Dead remains of living organisms provide nutrients to the soil. The excreta of earthworms makes the soil rich in calcium and nitrogen.

Time:

• Soil matures with the passage of time.
• The formation of soil is not a quick process. Rather, it takes thousands and millions of years to form.

 

Question 3. What is the role of living organisms in the formation of soil? Or, Soil formation is not only dependent on the weathering of rocks but also on living organisms. Can you explain how living organisms help in the formation of soil?
Answer:

Role of living organisms in the formation of soil:

Living organisms actually encompass both plants and animals.

1. Role of plants in the formation of soil:

1. Leaves, flowers, fruits, roots, etc decompose to form humus.
2. Leaves which have high contents of potassium, calcium, etc. decompose to form an acidic type of soil.
3. The water-holding capacity of soil increases when the organic matter present in the soil is more.

2. Role of animals in the formation of soil:

1. Ants, moles, earthworms and rats dig up holes in the soil thereby facilitating the formation of soil.
2. If the population of earthworm is high in soil, then the top layer of the soil becomes crystalline and the soil becomes rich in nitrogen and calcium.
3. Remnants of bacteria, algae and fungus decompose to form humus.
4. Human activities like the construction of buildings, afforestation, deforestation, etc. either facilitate or disrupt the formation of soil.

WBBSE Class 7 Geography Notes	WBBSE Solutions For Class 7 History
WBBSE Solutions For Class 7 Geography	WBBSE Class 7 History Multiple Choice Questions
WBBSE Class 7 Geography Multiple Choice Questions	WBBSE Solutions For Class 7 Maths

 

Question 4. How can you classify soil on the basis of the constituents present?
Answer:

Classification of soil on the basis of the constituents present:

On the basis of the constituents present, soil can be classified into three groups-

1. Sandy soil:

Soil which contains 80% or more sand, 10% silt and 10% clay with very little organic matter is called sandy soil. Some of the commonly grown crops in this soil are cucumber, muskmelon and watermelon.

2. Clayey soil:

Soil which contains 45-50% clay, 30-40% silt and 15-20% sand with little organic matter is called clayey soil. Generally, mango, jackfruit, paddy and wheat are grown in this soil.

3. Loamy soil:

Soil which contains an equal amount of sand (40%), silt (40%) and a smaller amount of clay is called loamy soil. Crops which are grown in this soil are potato, pointed gourd, paddy, wheat, mustard and jute.

Question 5. Make a comparative study of sandy, clayey and loamy soils.
Answer:

Comparative study of sandy, clayey and loamy soil:

A comparative study of sandy soil, clayey soil and loamy soil is discussed in the following table-

Question 6. What are the solid components of soil?
Answer:

Solid components of soil:

About 50% of the soil is composed of solid matter. Solid matter is divided into two parts-

1. Mineral component and
2. Organic component.

Mineral components include clay, sand, silt, etc. which make up about 45% of the soil. The remaining 5% consists of a black complex organic component called humus or organic component. Humus increases the fertility of the soil.

Question 7. What are the components of soil? Or, What is soil made of?
Answer:

Soil is formed of three major components-

1. Solid matter
2. Liquid matter and
3. Gaseous matter.

1. Solid matter:

50% of the total matter constitutes of solid matter. Out of this-

1. The mineral component is 45% and
2. The organic component is 5%. Out of this 5% organic component, 10% is micro- organisms, 10% is leaves and roots of plants and the rest 80% is decayed plants and animal remains, i.e. humus.

2. Liquid matter:

25% of the total matter constitutes of liquid matter or water.

3. Gaseous matter:

25% of the total matter constitutes of gaseous matter or air.

 

 

Question 8. What are the liquid and gaseous components of soil?
Answer:

Liquid component:

The liquid component of soil is water. Soil is composed of numerous pores, almost half of which is filled with water.

Gaseous component:

• The gaseous component of the soil is air. Air is not present throughout the volume of soil it is present in the pores which are not filled by water.
• Soil air accounts for about 25% of the soil.
• Soil air is less in moist or wet soil (about 20%) and more in dry soil (about 30%).

Question 9. Differentiate between rock and soil.
Answer:

The differences between rock and soil are

 

Question 10. What are the characteristics of sandy soil?
Answer:

The characteristics of sandy soil are-

1. The water-holding capacity of sandy soil is very low.
2. Good aeration is observed in this soil.
3. The soil particles are coarse in nature.
4. The organic content of this soil is less.
5. Sand particles are loosely packed.
6. Sandy soil absorbs water very quickly because it has very large spaces.
7. This soil is unsuitable for agriculture.

Question 11. Why is sandy soil unsuitable for cultivation?
Answer:

Sandy soil is unsuitable for cultivation because of the following reasons-

1. It contains more than 80% sand and is highly porous with low water-holding capacity. As a result, plants do not get their required water supply.
2. It can hardly store nutrients due to its large pore spaces. Thus, plants do not get the necessary nutrients required for their growth.

Question 12. Write down the characteristics of clayey soil.
Answer:

The characteristics of clayey soil are-

1. The water-holding capacity of clayey soil is very high.
2. Air hardly passes through its particles.
3. The soil particles are fine.
4. Clayey soil absorbs a very less amount of water because of fine soil particles and tiny pore space.
5. It is rich in organic matter.
6. Clayey soil is highly suitable for crop cultivation.

Question 13. Why does clayey soil have a high water-holding capacity?
Answer:

Clayey soil have a high water-holding capacity:

• The water-holding capacity of soil is highly dependent on its porosity. If the pore space between the soil particles is high, then the porosity of the soil increases but the water-holding capacity decreases, such as, in the case of sandy soil.
• On the other hand, the porosity of clayey soil is low. For this reason, the water-holding capacity of clayey soil is high. The soil particles in this case, are closely packed and are very fine.
• So, the porosity is low and water from the top layer does not flow rapidly into the bottom layers.

Question 14. What is loamy soil?
Answer:

Loamy soil:

Soil which contains an equal percentage of sand (40%), silt (40%) and a smaller amount of clay (20%) is called loamy soil. This soil can be of three types-

1. Sandy loam: In this soil, the amount of sand is slightly higher.
2. Clayey loam: The clay content of this soil is slightly higher.
3. Silty loam: In this soil, the predominance of silt is higher.

Question 15. What are the characteristics of loamy soil?
Answer:

The characteristics of loamy soil are-

1. The water absorption and air movement capacity of this soil are moderate.
2. Lime, iron and organic matter are present in the form of a mixture in this type of soil.
3. This soil has moderate water-holding capacity.
4. This soil is considered ideal for agricultural activities.

Question 16. What are the different uses of soil apart from agriculture?
Answer:

Soil is used in many other ways apart from agriculture. These are as follows-

1. Making clay utensils and idols:

Soil is used to make pots, cups, vessels and even bricks. It is also required for making idols.

2. Construction of house:

In rural areas, people make mud houses with the help of soil. In urban regions, sand is mixed with cement during construction works.

 

 

3. Raw material:

Clayey soil is the most important raw material for the cement industry.

4. Skincare:

Fuller’s Earth (commonly known as Multani Mitti) is commonly used as a part of one’s skincare routine.

5. Colourful motifs:

Chalk is used in making different colourful motifs like alpana and rangoli.

Question 17. What is Alluvial soil?
Answer:

Alluvial soil:

• Flooding of river banks results in the deposition of sand, silt, clay, mud etc., by the river thereby forming alluvial soil. The presence of silt makes this type of soil very fertile.
• Though it is deficient in nitrogen and humus, it is rich in potash and lime. This type of soil is suitable for growing paddy, wheat, jowar, bajra, pulses, oil seeds, cotton, vegetables, etc.

Alluvial soil can be further divided into three categories-

1. Sandy soil,
2. Clayey soil and
3. Loamy soil.

Question 18. Fill up the knowledge hive with information about igneous rocks.

Answers:

1. This rock is formed by the cooling and solidification of hot molten lava or magma.
2. This is a highly crystalline rock.
3. Stratification is not common in this type of rock.
4. Fossils are not found in this type of soil. 5. This is a hard rock.
6. The rock particles are very compact.

Question 19. Fill up the knowledge hive with information about granite.

Answers:

1. It is an intrusive igneous rock.
2. The rock has large crystals.
3. The rock crystals are mostly equal in size.
4. This is an acidic rock.
5. The relief formed of this rock is round-shaped.
6. This rock is abundant in the Deccan and the Chhotanagpur Plateau.

Question 20.

 

Across:

1. Fossils are found in this type of rock.
4. This type of soil contains equal amounts of sand and silt with a small amount of clay.
5. Metamorphosed form of granite.

Down:

2. Basalt is an example of ________ rock.
3. Continuous degradation of small rock fragments leads to the formation of a layer of degraded soil materials called.

Answers:

Across:

1. SEDIMENTARY,
4. LOAMY,
5. GNEISS

Down:

2. IGNEOUS,
3. REGOLITH

Question 21. Now make a survey of your locality.

Name of the district ______

Name of the village or the locality ______

Name of the surveyor ______, Class ______, Sec ______, Roll ______

School ______ Subject ______

Topic ______

1. The relief in your locality is flat/gently undulating/highly undulating.
2. Is there any forest or woods around?
3. What plants and trees do you commonly find around yourself?
4. What are locally cultivated vegetables?
5. Do you have paddy or jute fields around?
6. How would you describe the houses around you? How many ‘pucca’ houses do you find?
7. What are the ‘kutcha’ houses around you made of?
8. What is the dominant occupation of the people here?
9. What earthenwares are being manufactured in the locality?
10. Which type of soil do you think is found in your locality?

Answer:

Name of the district-Hooghly

Name of the village or the locality-Sripur

Name of the surveyor-Debdatta Roy, Class-VII, Sec-A, Roll-05

School-Sripur Radharani Vidyamandir for Girls’, Subject-Geography

Topic-Identification of the nature of the soil in my village.

Question 22. Differentiate between extrusive igneous rocks and intrusive igneous rocks.
Answer:

The differences between extrusive igneous rocks and intrusive igneous rocks are as follows-

WBBSE Chapter 6 Rock And Soil Topic B Soil Short Question And Answers

Question 1. What is soil?
Answer:

Soil:

• The word ‘soil’ is derived from the Latin word ‘solum’ meaning ground.
• For millions of years, various physical, chemical and organic processes have acted on the rocks causing them to disintegrate into smaller fragments.
• These fragments then mix with organic matter and form a thin layer on the Earth’s crust called soil.

Question 2. What constitutes the organic matter of soil?
Answer:

The organic matter of soil:

• An integral component of soil is its organic matter. Organic matter is formed from the dead and decayed remains of plants, animals and other microorganisms.
• Ants, moles, earthworms and snakes loosen the soil and allow water and air to pass through it.
• Dead remains of organisms supply nutrients to the soil. The abundance of organic matter is found in the topsoil giving it a dark colour.

Question 3. Which type of climate supports faster development of soil and why?
Answer:

Type of climate supports faster development of soil:

• Soil forms faster in warm and rainy climates. In such climates, due to high relative humidity,
• The disintegration of rock fragments as well as organic matter occurs faster.
• As a result of the faster decomposition of organic matter, the formation of humus also quickens.

Thus, these disintegrated rock fragments and humus combine to form soil at a much faster rate in warm and rainy climates.

Question 4. What is hummus?
Answer:

Hummus:

• Dead and decayed parts of plants and animals decompose over time to form a complex black-coloured substance called humus.
• Soil containing humus is very fertile with a high water-holding capacity. Plants like rose and tea grow well in soil containing humus.

Question 5. What are pore spaces?
Answer:

Pore spaces:

• The spaces between the soil particles which are not occupied by any solid material are known as pore spaces.
• Crop productivity and soil quality are highly dependent on the porosity of the soil.
• More the pore space, the lower is the water-holding capacity of soil and vice versa.

Question 6. Why is sandy soil called ‘thirsty soil’?
Answer:

Sandy soil called ‘thirsty soil’:

• Sandy soil contains more than 80% sand particles. As a result, water and other liquids seep through it very fast.
• On the other hand, this type of soil dries up fast as it is porous, irrespective of the continuous seepage and is thus, referred to as thirsty soil.

Question 7. Why does water drain faster in sandy soil?
Answer:

The porosity of sandy soil is higher as its grains are coarse in nature. So when water is poured into sandy soil, it drains very quickly.

Question 8. Which crops are grown on sandy soil?
Answer:

• Sandy soil has a high percentage of sand with very less amount of organic matter which makes it infertile. Desert vegetation (for example., baba, acacia) and dates grow well in sandy soil.
• But with the help of suitable irrigation methods watermelon, cucumber, pumpkin, bitter gourd, pointed gourd, and potato can be grown in sandy soil.

Question 9. Which crops are grown on clayey soil?
Answer:

• Clayey soil contains more clay and less sand particles.
• Since the water-holding capacity of this type of soil is high, the crops which require standing water during cultivation grow well in this soil such as paddy (Aus variety), jute, etc.
• Soft texture and predominance of clay make the soil suitable for mangrove vegetation like Sundari, Goran, ghewa etc.

Question 10. Which crops are grown on loamy soil?
Answer:

• As loamy soil is fertile, it is considered ideal for agriculture. This soil contains an equal percentage of sand and silt with a considerable amount of organic matter.
• Thus, paddy, wheat, sugarcane, jute, mustard and a variety of vegetables grow well in this type of soil.
• Evergreen trees like sissoo, garden, mahogany, rosewood, etc. and deciduous trees like sal, simul, mahua, and banyan form extensive forests in loamy soils.

Question 11. Tabulate the characteristics of different types of soil.
Answer:

The characteristics of different types of soil are tabulated here-

Question 12. What is a bedding plane?
Answer:

Bedding plane:

Sedimentary rocks are made of different strata or layers. Each layer is called ‘bed’ and the surface separating two adjacent beds is called ‘bedding plane’.

The characteristics of a bedding plane are-

1. The different strata or beds of sedimentary rocks can be separated.
2. Fossils are found along the beds of the bedding plane.

Question 13. Why are strata absent in igneous rocks?
Answer:

Strata are absent in igneous rocks because of the following reasons-

1. The fiery, hot molten material cools and solidifies to form igneous rock. Here, the minerals are integrated together resulting in the absence of layers or strata.
2. Since igneous rocks quickly solidify on cooling and form crystals, there is not enough time for the formation of strata.

Question 14. Why does metamorphism change the original properties of a rock?
Answer:

• Igneous rocks and sedimentary rocks metamorphose into a harder and more crystalline type of rock due to pressure created by extensive tectonic movements or due to the impact of hot, molten magma.
• This new type of rock formed is called metamorphic rock. Alteration of colour, texture, hardness and mineral composition occurs in this metamorphic rocks.
• Thus, the original properties change in metamorphic rocks due to high temperature and pressure.

Question 15. Why are the Himalayas formed of sedimentary rock?
Answer:

The Himalayan range is one of the most important young fold mountains in the world.

• This mountain range has been formed due to the upliftment of sediments deposited in the Tethys Sea as a result of the collision of the Indo- Australian and Eurasian plates.
• The uplifted sediments have been deposited through millions of years, transforming into sedimentary rocks.
• These rocks underwent folding and rose up. So, it is said that the Himalayas are formed of sedimentary rocks.

Real-Life Scenarios Involving Soil Conservation

Question 16. Why is mineral oil found in sedimentary rock?
Answer:

• Marine microorganisms like Foraminifera and aquatic plant cells get deposited in layers along with the sediments on the sea floor.
• Gradually, due to the high temperature of the Earth’s interior and excessive pressure due to overlying layers of sediments, extracts of the dead remains of these organisms get converted into compounds of carbon and hydrogen.
• These newly formed compounds are actually the mineral oil which is found in the strata of sedimentary rocks. It is also called ‘rock oil’.

Question 17. Prepare a table for the determination of rock types on the basis of the origin of rocks.
Answer:

 

Question 18. Prepare a table for the determination of rocks by identifying their characteristics.
Answer:

WBBSE Chapter 6 Rock And Soil Topic B Soil Very Short Question And Answers

Question 1. What is derived from regolith by different natural processes?
Answer: Soil.

Question 2. On which factor does the characteristics of a soil type depend?
Answer: Nature of rock(s) from which the soil is derived.

Question 3. State any two factors of soil formation.
Answer: Climate and relief.

Question 4. In which climatic region does soil formation occurs faster?
Answer: Warm and rainy climatic regions.

Question 5. Which type of slope supports better and gradual development of soil?
Answer: The gentler slope of the land.

Question 6. Which organisms play a significant role in the formation of soil?
Answer: Ants, moles, earthworms and snakes.

Question 7. What is formed when weathered rock debris mixes with hummus?
Answer: Soil.

Question 8. Which soil contains 80% sand, 10% silt and 10% clay?
Answer: Sandy soil.

Question 9. Name the soil that is loose and cannot be moulded even when wet.
Answer: Sandy soil.

Question 10. On which does watermelon, cucumber and pumpkin grow in abundance?
Answer: Sandy soil.

Question 11. Which soil is composed of bigger grains and has low water-holding capacity?
Answer: Sandy soil.

Question 12. Name the soil that is useful for making idols.
Answer: Clayey soil.

Question 13. Name the soil that has high water-holding capacity and becomes sticky when wet and hard when dry.
Answer: Clayey soil.

Question 14. Name the soil with fine particles that the potters prefer over other soil types.
Answer: Clayey soil.

Question 15. Which soil contains an equal percentage of sand, silt and clay and is suitable for agriculture?
Answer: Loamy soil.

Question 16. Name the soil that contains lime, iron and organic matter which make the soil suitable for agriculture.
Answer: Loamy soil.

Question 17. Name the soil that is preferred by farmers for agriculture.
Answer: Loamy soil.

Question 18. Name the black-coloured soil that is derived from basalt.
Answer: Regur or Black soil.

Question 19. I am an important constituent of the Earth’s crust. I am made of one or more minerals. Who am I?
Answer: Rock

Question 20. I form rocks. I am a naturally occurring inorganic substance. Who am I?
Answer: Mineral

Question 21. I was formed during the Earth’s origin and am also called primary rock. Who am I?
Answer: Igneous Rock

Question 22. I am a type of rock formed by the deposition of sediments on the Earth’s surface and within waterbodies. Who am I?
Answer: Sedimentary rock

Question 23. I am a black sedimentary rock used as a fossil fuel. Who am I?
Answer: Coal

Question 24. I am a mixture of weathered or eroded rock debris and organic matter. Who am I?
Answer: Soil

Question 25. I am a soil, that is sticky when wet and hard when dry. Who am I?
Answer: Clayey Soil

Question 26. I am the impression of plants and animals found in the sedimentary rock beds. Who am I?
Answer: Fossil

Question 27. I am a type of soil formed of loose rock fragments and have low water-holding capacity. I am ideal for crops such as watermelon, peaches and peanuts. Who am I?
Answer: Sany soil

Question 28. I am the ideal soil type for gardening and agricultural purpose and is a favourite of the farmers. Who am I?
Answer: Loamy soil

Question 29. I am a type of soil formed by the accumulation of silt on river banks. Who am I?
Answer: Alluvial soil

Question 30. I am a black rock formed by the rapid cooling of lava. Who am I?
Answer: Basalt

Question 31. I am a rock of volcanic origin. Who am I?
Answer: Igneous rock

Question 32. I am a sedimentary rock used in the iron and steel industry. Who am I?
Answer: Limestone

Question 33. I am the metamorphosed form of limestone. The Taj Mahal is made of me. Who am I?
Answer: Marble

Question 34.  I am a soil made from basalt. Who am I?
Answer: Regur Soil

WBBSE Chapter 6 Rock And Soil Topic B Soil Find The Odd One Out

Question 1. Alum: Rock salt: Gold: Marble
Answer: Marble (not a mineral)

Question 2. Mudstone: Limestone: Granite: Sandstone.
Answer: Granite (not a sedimentary rock)

Question 3. Granite: Gneiss: Basalt: Gabbro
Answer: Gneiss (not an igneous rock)

Question 4. Marble: Slate: Graphite: Granite
Answer: Granite (not a metamorphic rock)

Question 5. Laterite: Silt: Sand: Clay
Answer: Laterite (not a soil component)

Question 6. Igneous rock: Sedimentary Metamorphic rock: Quartz rock:
Answer: Quartz (not a type of rock)

WBBSE Chapter 6 Rock And Soil Topic B Soil Correct The Following

Question 1. The rock that can be found near a railway line is granite rock.
Answer: Basalt

Question 2. Rock is formed from regolith.
Answer: Soil

Question 3. Taj Mahal is constructed of basalt.
Answer: Marble

Question 4. Metamorphic rocks are the softest and brittle.
Answer: Sedimentary

Question 5. Sandy soil is composed of very fine grains.
Answer: Clayey

Question 6. Clayey soil is best for agriculture.
Answer: Loamy

Question 7. Metamorphic rocks are formed by the solidification of lava or magma.
Answer: Igneous

Question 8. The transformation of rocks from one type to another is known as the water cycle.
Answer: Rock

WBBSE Chapter 6 Rock And Soil Topic B Soil Fill In The Blanks

Question 1. The word ‘soil’ has originated from the Latin word ________.
Answer: Solum

Question 2. The dead and decayed parts of plants and animals found in soil are collectively called ________.
Answer: Humus

Question 3. According to composition, soil can be classified into ________ types.
Answer: Three

Question 4. Dead and decomposed remains of microorganisms mix with the soil to form ________ matter.
Answer: Organic

Question 5. Soils of coastal regions have a high percentage of ________ in it.
Answer: Salt

Question 6. The water-holding capacity of ________ soil is very less.
Answer: Sandy

Question 7. ________ Soil is very good for the cultivation of muskmelon.
Answer: Sandy

Question 8. ________ soil is very good for the cultivation of muskmelon.
Answer: Clay

Question 9. Saline soil is found in ________ of West Bengal.
Answer: Sundarban

Question 10. Low water-holding capacity: Sandy soil:: High water-holding capacity:_______.
Answer: Clayey soil

Question 11. Low fertility: Sandy soil:: High fertility: _______.
Answer: Sandy soil

Question 12. Coarse grain :_______:: Fine grain Clayeysoil.
Answer: Loamy soil

WBBSE Chapter 6 Rock And Soil Topic B Soil True Or False

Question 1. Sandy soil is the ideal soil for cultivation.
Answer: False

Question 2. The saline soil of the Sundarbans is alkaline in nature.
Answer: True

Question 3. Mountain soil is found in the Darjeeling district.
Answer: True

Question 4. Alluvial soil is stratified.
Answer: False

Question 5. Snow-capped mountain soil is unsuitable for human habitation.
Answer: True

Question 6. Plants grow on rock debris.
Answer: False

Question 7. The thin hard covering on the Earth’s surface is called soil.
Answer: False

Question 8. Watermelon grows abundantly in soil containing humus.
Answer: False

Question 9. Sand and clay are found in equal percentages in loamy soil.
Answer: True

Question 10. Weathering has no role in soil formation.
Answer: False

Question 11. High humus content makes the soil blackish in colour.
Answer: True

Question 12. 25% of the soil is made of water.
Answer: True

WBBSE Chapter 6 Rock And Soil Topic B Soil Scrambled Words

1. TASEMENDIRY
2. TAMEPHMORIC
3. TISTFITICAONRA
4. LIGORETH
5. SSOFLI
6. OUSNEIG

Answers:

1. SEDIMENTARY
2. METAMORPHIC
3. STRATIFICATION
4. REGOLITH
5. FOSSIL
6. IGNEOUS

WBBSE Chapter 6 Rock And Soil Topic B Soil Match The Columns

Question 1.

Answer: 1. B, 2. C, 3. A, 4. E, 5. D

Question 2.

Answer: 1. D, 2. E, 3. C, 4. B, 5. A