Chapter 8 Human Food And Food Production Answer in One or Two sentences
Question 1. Where do we obtain our food?
Answer:
We obtain our food from plants and animal, resources.
Question 2. What is the name of the branch of science which deals with the process of food production?
Answer:
The branch of science is agriculture.
Question 3. Name two plant resources that we consume as food.
Answer:
These are rice, wheat, etc.
Question 4. Name two animal resources that we consume as food.
Answer:
These are milk, egg, meat, etc.
Question 5. What is a crop?
Answer:
Crop:
When the same plant is cultivated in a large area, it is collectively termed a crop.
Read And Learn More WBBSE Solutions For Class 8 School Science Very Short Answer Type Questions
Question 6. Name two cereal crops.
Answer:
Two cereal crops:
These are paddy, wheat, etc.
Question 7. Name two tuber crops.
Answer:
Two tuber crops:
These are potatoes, ginger, etc.
Question 8. Name two sugar crops.
Answer:
Two sugar crops:
These are sugarcane and beet.
Question 9. Name two medicinal crops.
Answer:
Two medicinal crops:
These are tulsi, sharp and etc.
Question 10. Name two decorative plants.
Answer:
Two decorative plants:
These are cactus, bougainvillea, etc.
Question 11. What are Kharif crops?
Answer:
Kharif crops:
The crops whose cultivation depends upon monsoon are called Kharif crops. Examples- Paddy, Maize, Cotton, etc.
Question 12. What are rabi crops?
Answer:
Rabi crops:
The winter season crops, whose cultivation does not depend upon monsoon, are called rabi crops. Examples – Wheat, Barley, Mustard, etc.
Question 13. What is the medium of germination of seed?
Answer:
Medium of germination of seed:
Generally soil is the medium for the germination of seeds.
Question 14. Mention one reason for turning off the soil before sowing of seed.
Answer:
The soil will become loose and the roots of plants will easily penetrate into it.
Question 15. Does Sandy soil need frequent irrigation-why?
Answer:
Due to the poor water retaining capacity Of sandy soil, the crops cultivated in sandy soil need frequent irrigation.
Question 16. Why earthworm is considered a ‘farmer’s friend’?
Answer:
The earthworm present in the soil, help in loosening the soil and increase the organic content or humus of soil.
Question 17. Name a soil bacteria, which helps in agriculture.
Answer:
Rhizobium is a soil bacteria that help in agriculture.
Question 18. Name the tools for plowing.
Answer:
Tools for plowing:
These are plow, hoe, cultivator, etc.
Question 19. How a good seed can be identified for sowing?
Answer:
Good healthy seeds sink in water but spoiled seeds float on the water’s surface.
Question 20. Name an instrument for sowing seeds in the soil.
Answer:
A seed drill can be used for sowing seeds.
Question 21. Name one macronutrient and one micronutrient of soil, required for plant growth.
Answer:
Macronutrient is carbon and micronutrient is iron.
Question 22. How organic manures are produced in soil?
Answer:
Organic manures are produced by the decomposition of dead animals, plants, and their wastes.
Question 23. What are inorganic fertilizers?
Answer:
Inorganic fertilizers:
Inorganic fertilizers are chemical substances required for plant growth. Example- superphosphate.
Question 24. Mention one advantage of organic manure over inorganic fertilizer.
Answer:
Organic manure helps the growth of beneficial bacteria in soil, while excess inorganic fertilizer may reduce them.
Question 25. What is crop rotation?
Answer:
Crop rotation:
In crop rotation, different crops are raised from some land, at different seasons.
Question 26. What is the benefit of crop rotation?
Answer:
Benefit of crop rotation:
It replenishes the soil nutrients used during cultivation.
Question 27. What is irrigation?
Answer:
Irrigation:
Irrigation is the method of water supply to crop fields.
Question 28. Name two sources of irrigation.
Answer:
Two sources of irrigation:
Generally water from rivers, canals, tube wells, etc. is used for irrigation.
Question 29. What are weeds?
Answer:
Weeds:
Weeds are undesirable vegetation in a crop field.
Question 30. Name a chemical used to destroy weeds.
Answer:
Examples of weedicides are – Dalapon, 2, 4- D(2, 4-Dichlorophenoxyacetic acid).
Question 31. What is an insecticide? Give an example.
Answer:
Insecticide:
The chemicals Which kill insects are known as insecticides. Examples are DDT, BHC, etc.
Question 32. What is biological control of pests?
Answer:
Biological control of pests:
The process by which pest organisms are controlled by other organisms, which may be their predator or parasite and also at the same time harmless for humans, is known as biological control
Question 33. Are the terms insecticides and pesticides synonymous?
Answer:
Pesticides and insecticides are not synonymous. Insecticide destroys only insects but pesticides will kill any pest, which may or may not be an insect. For example, rat-killing poison is a pesticide but not an insecticide.
Question 34. What are silos?
Answer:
Silos:
Silos are airtight chambers for storing food grains.
Question 35. Why nitrogen gas is circulated through grannies?
Answer:
Pests can not survive in a medium containing high nitrogen.
Question 36. State the utility of rice bran.
Answer:
Utility of rice bran:
Oil is produced from rice bran.
Question 37. Name the winter paddy and summer paddy.
Answer:
Winter paddy is known as a man; summer paddy Is known as boro.
Question 38. What is golden rice?
Answer:
Golden Rice:
It is a special type of rice containing high vitamin-A. Agricultural scientists have created this variety.
Question 39. What amount of standing water in the field is needed for paddy cultivation?
Answer:
About 30-50 mm of standing water is needed.
Question 40. Which fruit is considered the king of fruits?
Answer:
Mango is considered the king of fruits.
Question 41. To which country, mango is indigenous?
Answer:
Mango is indigenous to India.
Question 42. Name the common vitamins found in mango.
Answer:
Mango contains vitamins A, B complex, and C.
Question 43. Name the varieties of mangoes of West Bengal which mature first and last in a season.
Answer:
Golapkhas matures first and Jhumkophajli matures last.
Question 44. What is the most common way of grafting of mango plant, for its propagation?
Answer:
Anarching is the most common way of mango grafting.
Question 45. Name two states of India, whose tea production is maximum.
Answer:
In India maximum tea grows in Assam and West Bengal.
Question 46. Name two substances present in tea, which stimulate our body.
Answer:
These two substances are caffeine and pantothenic acid.
Question 47. What is special about green tea?
Answer:
Green Tea:
Green tea contains vitamin K which prevents internal hemorrhages, myocardial infarction, rheumatic inflammations, etc.
Question 48. Write about the propagation of tea plants.
Answer:
Propagation takes place from seeds or by single node cuttings.
Question 49. What parts of tea plants are used for tea manufacture?
Answer:
Generally one bud and two or three leaves are used.
Question 50. Where do natural beehives develop?
Answer:
Beehives generally remain suspended from trees and crevices or cornices of houses.
Question 51. Name the different casts of a bee colony.
Answer:
Different casts are—queen, male or drone, and workers.
Question 52. How do the worker bees produce honey?
Answer:
Worker bees produce honey by mixing the nectar of flowers with their saliva.
Question 53. Name the life cycle stages of honeybees.
Answer:
The life cycle stages are— egg, larva, pupa, and adult.
Question 54. Why apiary is to be established near flower-erring plants.
Answer:
Because worker bees collect nectar from flowering plants
Question 55. What is Fishery?
Answer:
Fishery:
Fishery is the culture and capture of economically important aquatic animals like fish, prawns, pearls, etc.
Question 56. What is pisciculture?
Answer:
Pisciculture:
Pisciculture is the culture and capture of fish.
Question 57. What is a fish?
Answer:
Fish:
True fish is a red-blooded vertebrate animal.
Question 58. What are carps?
Answer:
Carps:
Carps are freshwater edible, toothless bony fishes, that have swim bladders and body (except the head region) covered with scales.
Question 59. What are spawns?
Answer:
Spawns:
Sperms and eggs of fishes unite to produce spawns.
Question 60. What is fry?
Answer:
Fry:
The fishlings, released from fertilized eggs, up to the length of 25 – 40 mm are called fry.
Question 61. What are fingerlings ?
Answer:
Fingerlings:
These are small fishlings up to the size of 40 – 100 mm.
Question 62. Name the Indian major carps used in composite fish culture.
Answer:
These are rohu, mrigel and katla.
Question 63. Where in Kolkata, large scale sewage-fed fish culture performed?
Answer:
It is performed in the berries in East Kolkata.
Question 64. What are poultry birds?
Answer:
Poultry Birds:
Economically important birds are known as poultry birds. Examples—Fowls, Ducks, etc.
Question 65. Give an example of the light, non-sitter fowl breed.
Answer:
Leghorn is a light, non-sitter fowl breed.
Question 66. Give an example of the heavy, sitter poultry breed.
Answer:
Brahma is a heavy, sitter poultry breed.
Question 67. What is a broiler?
Answer:
Broiler:
Broiler is a type of hybrid fowl, created mainly for obtaining meat.
Question 68. What is intercropping?
Answer:
Intercropping:
The practice of growing two or more crops simultaneously on the same field in a definite pattern is called intercropping.
Question 69. Name two diseases of honey bees.
Answer:
Two diseases of honey bees:
Nosema and Acarine disease.
Question 70. What is the role of polyphenols present in tea?
Answer:
Polyphenols present in tea reduces blood cholesterol and helps to prevent cancer due to their antioxidant property.
Question 71. Which type of carp is punti?
Answer:
Minor carp.
Question 72. Name the vitamin contained in the egg.
Answer:
Eggs are rich in vitamins A, D, E, and B-com- plex.
Question 73. Mention a modern feature that is employed in the storage of food grains.
Answer:
Nitrogen gas is continuously circulated inside silos to prevent pests.
Question 74. What is polyculture?
Answer:
Polyculture:
Polyculture of fishes employs scientific fish farming where several species of fish (both local and imported) are cultured at the same time in the same pond.
Question 75. Mention some desirable agronomic characteristics of fodder crops.
Answer:
Profuse branching and tallness.