WBBSE Solutions For Class 10 Life Science And Environment Chapter 4 Theories Of Organic Evolution

Chapter 4 Theories Of Organic Evolution Summary

Theory Of Organic Evolution

• There are various theories regarding evolution, of which Lamarckism and Darwinism are the most significant.
• In the year 1809, Lamarck published his book ‘Philosophie Zoologique’ where he proposed and explain his theories regarding the evolution of new species.
• The main features of the theory of Lamarck are-

1. Internal vital force
2. New needs culminate in the formation of the new organ
3. Law of use and disuse of an organ
4. Inheritance of acquired characters
5. Formation of new species

• German biologist August Weismann conducted an experiment where he removed the tails of mice repeatedly over 22 generations and reported that no mice were born in consequence without a tail or even with a shorter tail.
• This experiment opposed the theory of inheritance of acquired characters of Lamarck. Charles Robert Darwin sailed around the world, as a naturalist, aboard the HMS Beagle and this experience and studies that he made, helped him to propose the theory of evolution which was published in his book, ‘Origin of Species by Means of Natural Selection’.
• The salient features of the theory of Darwin are-

Life Science Class 10 Wbbse

1. Prodigality of production
2. Limited food and shelter on earth
3. Struggle for existence
4. Variations
5. Survival of the fittest
6. Natural selection
7. Origin of new species

• Few limitations of Darwin’s theory concern the origin of variation, the origin of new characters, the arrival of the fittest, etc.

Read and Learn More WBBSE Solutions for Class 10 Life Science And Environment

Chapter 4 Theories Of Organic Evolution Long Answer Type Questions

Question 1. Briefly describe the Lamarckian concept of evolution. Part question, Describe two major tenets of Lamarck’s evolutionary theory.

Answer:

Lamarckian concept of evolution:

In 1809, Lamarck proposed the concept of organic evolution in his famous book, titled ‘Philosophie Zoologique. This concept is popularly known as Lamarckism.

Lamarckism is based on the following basic propositions.

Wbbse Class 10 Life Science Solutions

1. Internal vital force:

An internal vital force or energy in all life forms helps in the development of the body and organs.

2. Development of new organs according to need:

With the change in environment, a need develops among the organisms for morphological and behavioural change. Newly developed organs help the organisms to adapt in the changing environment.

3. Law of use and disuse:

Any organ, which is used more, grows in size and strength, whereas, that which is used less, reduces in size, becomes weak and finally becomes extinct.

Example of use of organ:

Ancestors of giraffes had short necks. To collect the leaves of taller plants, they stretched their necks continuously. This conscious effort made their necks long and eventually, giraffes with longer necks evolved.

Example of disuse of organ:

The ancestors of snakes had limbs. While adapting to the fossorial habitat, their limbs were left unused. Finally, limbs. of snakes were lost during the course of evolution.

4. Inheritance of acquired characters:

Any change in the characteristics of an organism, which an organism achieves by conscious effort, is inherited by its offspring.

5. Formation of new species:

The characters acquired during the lifetime are passed onto the progeny and after a number of generations, new species is produced.

To get leaves from tall trees, ancestors of giraffes stretched their necks. By this process, one might have lengthened it a little, which was inherited directly by its offspring.

This process continued for several thousand generations and finally completely different-looking long-necked giraffes emerged as a new species from their ancestors.

Wbbse Class 10 Life Science Solutions

Question 2. What is meant by the ‘Inheritance of acquired characters’? Explain with an example. Mention the demerits in the Lamarckian concept of evolution.

Answer:

Inheritance of acquired characters:

According to Lamarck, any feature that organisms acquire during its conscious effort to adapt in to an environment is inherited by its offspring. This event is known as the ‘Inheritance of acquired characters.

Example:

The necks of ancient giraffes were short. With a continuous effort to reach the leaves of taller trees, they stretched to lengthen their necks. The little change achieved by this process in one generation was inherited by the next.

This process continued for several successive generations and gradually long-necked giraffes have arrived as a new species.

Demerits of Lamarckism:

1. The law of use and disuse is not universally accepted. In some cases, active organs may reduce in size in the course of evolution.
2. Only internal vital force cannot develop a new organ. An aquatic animal cannot become a terrestrial animal only by internal desire.
3. Continuous use of any organ never always makes an organ stronger. The heart, for instance, never becomes larger and stronger with time.
4. Inheritance of acquired characters is not always evident. No somatic change is inherited by the next generation, it may occur only in case of any change in the germ cells.

Wbbse Class 10 Life Science Solutions

In this connection, Weismann’s experiment may be cited. He cut the tails of newborn rats for 22 successive generations; however, tail-less rats were never born.

Similarly, Drosophila flies were reared in complete darkness for 60 successive generations, but no blind fly was born. Based on this observations, Weismann strongly opposed the Lamarckian concept of inheritance of acquired characters.

Question 3. Explain the Darwinian concept on organic evolution. Part Questions, Discuss the following three events as mentioned in the evolutionary theory of Darwin:

1. The prodigality of production,
2. Origin of variation,
3. Natural selection

Answer:

Darwinian concept on organic evolution:

In 1859, Charles Darwin explained the modern concept of organic evolution in his famous book ‘On. the Origin of Species by Means of Natural Selection, which has become famous as Darwinism or as the theory of natural selection. The basic thoughts of Darwinism are mentioned below.

1. Prodigality of production:

Darwin opined that all organisms increase their population in a geometric rate. For example, a pond snail lays 6 million eggs in a year. A female salmon fish releases 30 million eggs in a reproductive season.

2. Limited food and shelter on earth:

The space on the earth and supply of food do not increase in proportion to the rate of increase in population. Therefore, a scarcity of food and shelter occurs in the living world.

3. Struggle for existence:

Continuous increase in population size and scarcity of food and shelter results in to conflicts among the organisms for survival. Darwin referred to it as the struggle for existence. This struggle is of three types-

1. Intraspecific struggle-The conflict among the members of a same species population for food, shelter and mating partners.
2. Inter-specific struggle-The- conflict among the members of different species for resources and shelter.
3. Environmental struggle- This struggle is for surviving different natural calamities, like drought, flood, earthquake, etc.

Wbbse Class 10 Life Science Solutions

 

4. Variation:

Darwin indicated that no two individuals of the same species are identical. There must be some differences between them, which he stated as variations.

5. Survival of the fittest:

Darwin mentioned two different types of variations-favourable and unfavourable. Favourable variations help an organism to adapt to changing environment but unfavourable variations cannot help in their adaptation.

The individuals with unfavourable variations face a defeat in the struggle for existence and become extinct in the course of time. Whereas, the organisms with favourable variations win that struggle and survive on Earth.

Scientist Herbert Spencer denoted this event as the ‘survival of the fittest.

6. Natural Selection:

According to Darwin, organisms with favourable variations are selected by nature for survival because they are fittest to face their surroundings. Darwin explained this event as ‘natural selection.

The naturally selected forms thrive successfully and propagate very fast to increase their population.

7. Origin of new species:

Accumulation of many favourable variations in any group of organisms for generations makes their descendants widely different from their ancestors. Finally, these completely changed descendants emerge as new species.

Question 4. What is natural selection? Mention the drawbacks of Darwinism. Part question, Explain the process of natural selection as proposed by Darwin with the help of a suitable example.

Answer:

Natural selection:

Natural selection means the selection of a suitable organism in an environment by nature itself. According to Darwin, organisms acquire either favourable or unfavourable variations during their struggle for existence.

Those with favourable variations are selected by nature. They can adapt perfectly with its environment and come out victorious in the struggle for life. They thrive successfully and propagate quickly.

On the other hand, the organisms, which have unfavourable variation, do not get the favour of natural selection and cannot adapt themselves in their environment. The population of these forms reduces gradually and finally, becomes extinct.

For example, in an ecosystem, some giraffes have long necks and others have short necks. If a situation arises, where there is a scarcity of low-lying shrubs, the giraffes with short necks would not get enough food. After a few generations, all the giraffes would have long necks.

 

Wbbse Class 10 Life Science Solutions

Drawbacks of Darwinism:

1. Darwin mentioned the role of variation in evolution but could not explain the sources of it.
2. Darwin emphasised on small variations but in reality, small variations play no role in the origin of species.
3. Darwin supported the concept of survival of the fittest, however, he could not explain the cause of the emergence of the fittest.
4. According to Darwin, excessive development of any organ facilitates evolution but it is seen that over-specialisation often pushes a species towards extinction.
5. Darwin did not differentiate between somatic and reproductive variations.
6. During natural calamities, even the fittest organisms also die, where natural selection does not operate.

Question 5. What is ‘survival of the fittest’? Explain how do certain organs become vestigial giving examples of few vestigial organs in animals and plants.

Answer:

Survival of the fittest:

Here, the word ‘fittest’ means, the most competent individual or group among a number of individuals or groups. On the other hand, ‘survival’ means coming out victorious in the struggle for existence.

During the struggle for existence in a hostile environment, certain organisms acquire some favourable variations, which help them to survive in the struggle. However, there are some other organisms, which have unfavourable variations, cannot overcome environmental barriers and gradually become extinct.

Therefore, the fittest organisms win the battle for survival and thrive successfully. Herbert Spencer denoted this event as ‘survival of the fittest’.

 

The emergence of vestigial organs:

Certain organs, which were once active and useful in ancestors, may become non-functional and weak in their descendants due to continuous disuse in the changed environment. Thus, certain active organs transform into vestigial and inactive organs.

1. Example of vestigial organs in animals:

Muscles of the pinna, the nictitating membrane of the eye, vermiform appendix are a few examples of vestigial organs in man. The pelvic girdle bones of a whale, and wings of ostrich are some vestigial organs of other animals.

2. Example of vestigial organs in plants:

Scale leaves of underground-modified stems, sterile gynoecia of coconut, staminodes of Cassia, and scale-like leaves of Cuscuta are some vestigial organs in plants.

Question 6. Explain the process of lengthening of giraffe’s neck under the light of Lamarckism and Darwinism.

Answer:

Explanation of lengthening of giraffe’s neck:

Lamarck and Darwin, the two pioneer figures of evolutionary science, explained the event of gradual lengthening of the giraffe’s neck in two different ways.

1. Lamarckian explanation:

Lamarck believed that the necks of the ancestors of giraffes were almost similar to that of recent horses. To reach the leaves of taller trees they used to stretch their necks continuously.

In this process, members of every generation lengthened their necks to a little extent. This changed feature was inherited by the next generation and this process continued for several successive generations.

Finally, after thousands of generations, the long-necked giraffes have emerged as a new species.

2. Darwinian explanation:

According to Darwin, in ancient days members of the giraffe population had various lengths of necks. Those with longer necks could reach the leaves of taller trees and hence got more food than the ones with shorter necks.

The long-necked giraffes became healthier and thrived successfully. On the other hand, the short-necked giraffes became weaker and reproductively incapable due to a shortage of adequate food.

Gradually, the number of these giraffes went down and at the end they became extinct. However, the long-necked giraffes came out victorious in the struggle for existence and survived on earth as a new species.

Question 7. Distinguish between Lamarckism and Darwinism.

Answer:

Distinguishing features between Lamarckism and Darwinism

 

Chapter 4 Theories Of Organic Evolution Short Answer Type Questions

Question 1. What made Lamarck famous?

Answer:

Lamarck :

Lamarck is famous for his two theories on organic evolution.

These are-

1. Law of use and disuse and
2. Law of inheritance of acquired characters.

Question 2. What do you mean by the ‘law of use and disuse’? Or, Mention the ‘law of use and disuse’ in relation to organic evolution.

Answer:

‘Law of use and disuse’:

According to Lamarck, any organ that is used more, becomes stronger and well built, whereas Put emphasis on three different types of struggles for existence; intra- specific struggle, inter-specific struggle and struggle any unused organ becomes weak and reduces in the course of time. This theory is known as the ‘law of use and disuse.

For example, flightless birds have evolved from their flying ancestors. As the ancestor birds do not use wings, their wings become vestigial structures.

Wbbse Class 10 Life Science Solutions

Question 3. What is meant by ‘inheritance of acquired characters’?

Answer:

‘Inheritance of acquired characters’:

According to Lamarck, the change in characteristics, which an organism acquires in the course of its adaptation to a changing environment, is inherited by its offspring.

These characteristics are also carried to successive generations. This proposition is known as the ‘inheritance of acquired characters.

Question 4. What is meant by germplasm theory?

Answer:

Germplasm theory:

According to Weismann, the inheritable features are never carried by the somatic cells from – parents to offspring. Only the germ cells carry these characteristics from one generation to the next. This concept is known as the germplasm theory.

Question 5. What is Neo-Lamarckism?

Answer:

Neo-Lamarckism:

A number of modern scientists, viz., Waddington, Packard, Spencer and others modified the original theory of Lamarck under the light of the interaction between life and the environment. This modified form is known as Neo-Lamarckism.

Question 6. Why was Charles Darwin famous?

Answer:

Charles Darwin:

In 1859, Charles Darwin published his concept on organic evolution in his book, titled ‘On the Origin of Species by Means of Natural Selection. In his book, he explained the role of natural selection on the origin of new species from an older one.

This theory of natural selection made Darwin famous in the field of biology.

Question 7. What is meant by a struggle for existence?

Answer:

A struggle for existence:

To survive on the earth, every individual organism has to face competition for food, shelter and mating partners. In this context, it comes across either with the members of the same species or that of different species.

Apart from this, it has to fight against different natural adversities, like floods, droughts, volcanic eruptions, forest fires, etc. Charles Darwin described all these conflicts as the struggle for existence.

Question 8. How many types of the struggle for existence did Darwin suggest?

Answer:

Darwin suggested three different types of struggle for existence among the organisms on Earth.

These are-

1. Intra-specific struggle (competition among the members of the same species),
2. Inter-specific struggle (competition among the members of different species) and
3. Environmental struggle or the struggle against nature (struggle against different natural calamities).

Question 9. What is an intra-specific struggle?

Answer:

Intra-specific struggle:

Members of the same species often get involved in conflict with each other for food, shelter and mating partners. Darwin explained this type of conflict as an intra-specific struggle.

Example: Dogs often fight among themselves for food and mating partners.

Wbbse Class 10 Life Science Solutions

Question 10. What is an inter-specific struggle?

Answer:

Inter-specific struggle:

Members of different species often fight with each other for food and shelter. Darwin explained this type of conflict as an inter-specific struggle.

Example: Dogs fighting with cats for the same food, sparrows fighting with common myna for food and shelter.

Question 11. Tigers are extinct but there are many deer in the jungle. A few tigers are brought from another sanctuary and released in such a jungle. Imagine and write the names of different kind of struggles for existence those tigers have to be involved in.

Answer:

The tigers, brought from another sanctuary, have to face mainly two types of struggle for existence.

These are-

Inter-specific struggle:

They have to get involved in an inter-specific struggle with deer for food.

The struggle against nature:

Firstly, the tigers will face difficulty in adjusting with the new environment and secondly, as the number of deer is high in that jungle, the jungle will be devoid of bushes which generally provide hiding space to tigers during hunting sessions.

Question 12. A good number of Tilapia fishes are released in a pond having only different indigenous fish species grown naturally. Think and write which types of a struggle for existence Tilapia fishes have to face in order to survive.

Answer:

The Tilapia fishes have to face three types of struggle for existence in the pond where they are released.

These are

Intra-specific struggle:

It is the struggle among all the newly released tilapia fishes for food and habitat

Inter-specific struggle:

It is the struggle between Tilapia and other naturally grown indigenous fishes for food and habitat.

Struggle with the environment:

Life Science Class 10 Wbbse

The Tilapia fishes struggle with the condition of the pond where they are newly released. Water content, Temperature of water, amount of dissolved oxygen, poisonous substances present in that pond water, etc. are the obstacles that they struggle against, to overcome.

Question 13. What is the variation?

Answer:

Variation:

The distinctive feature that separates one individual of a species from the other members of the same species is called variation. The difference in the colour of the human eye is an example of variation.

Question 14. What are favourable and unfavourable variations?

Answer:

Favourable variations:

According to Darwin, the variations, which help an organism to stay alive in the struggle for existence, are known as favourable variations.

Unfavourable variations:

According to Darwin, certain variations do not help an organism to survive in its struggle for existence but rather push them towards extinction. These variations are called unfavourable variations.

Question 15. How did Darwin apply the evidence of comparative embryology in his theory of evolution?

Answer:

Charles Darwin applied the concept of Von Baer’s comparative embryology in his evolutionary thought. According to him, embryo-logical similarity indicates the same ancestral lineage.

He also opined that the special features, which develop in the embryonic state, help an animal to adapt in its environment.

Question 16. What is mutation? Who is the proponent of the mutation theory?

Answer:

1. Mutation:

Any sudden, stable and inheritable change in a chromosome or gene that may or may not have a direct impact on the phenotype of an individual, is called a mutation.

2. Proponent: Hugo de Vries is the proponent of the mutation theory.

Question 17. What is the synthetic theory of evolution?

Answer:

Synthetic theory of evolution:

Modern scientists have found certain drawbacks of the Darwinian theory of evolution. Without completely discarding it, they added several new concepts to the basic natural selection theory under the light of modern scientific facts.

The compilation of all these concepts has developed a new theory of evolution, popularly known as the synthetic theory of evolution.

Question 18. Mention the he four main foundations of the synthetic theory of evolution.

Answer:

The synthetic theory of evolution is built on four main foundations.

These are-

1. Gene mutation,
2. Chromosomal aberration,
3. Recombination of genes and
4. Natural selection.

Question 19. What is Neo-Darwinism?

Answer:

Neo-Darwinism:

Modern scientists, viz. Morgan, Haldane, Dobjhansky and others modernised the original Darwinian theory of evolution by incorporating the concepts of variation, isolation, mutation and genetics into it.

This renewed and updated Darwinian theory of evolution is known as Neo-Darwinism.

Life Science Class 10 Wbbse

Chapter 4 Theories Of Organic Evolution Very Short Answer Type Questions Multiple Choice Questions And Answers [Mcq]

Question 1. Which of the following can be explained by the theory of natural selection?

1. Over specialisation
2. Discrete variation
3. Survival of the fittest
4. Vestigial organ

Answer: 3. Survival of the fittest

Question 2. The author of the famous book, ‘Philosophic Zoologique’ was—

1. Darwin
2. Weismann
3. Lamarck
4. Hugo de Vries

Answer: 3. Lamarck

Question 3. The author of the famous book, ‘On the Origin of Species by Means of Natural Selection was—

1. Lamarck
2. Hugo de Vries
3. Darwin
4. Spencer

Answer: 3. Darwin

Question 4. Who first used the statement ‘struggle for existence’?

1. Darwin
2. Lamarck
3. Mendel
4. Weismann

Answer: 1. Darwin

Question 5. Who propounded the theory of natural selection?

1. Lamarck
2. Darwin
3. Mendel
4. Weismann

Answer: 2. Darwin

Question 6. Who proposed the concept that organisms are evolved from mutation? Or, Who proposed the theory of mutation?

1. Osborn
2. Cuvier
3. Weismann
4. Hugo de Vries

Answer: 4. Hugo de Vries

Question 7. Determine the term related to the theory of Lamarck.

1. Struggle for existence
2. Origin of variation
3. Inheritance of acquired characters
4. Natural selection

Answer: 3. Inheritance of acquired characters

Question 8. The Lamarckian concept of inheritance of acquired characters was opposed by—

1. Osborn
2. Cuvier
3. Darwin
4. Weismann

Answer: 4. Weismann

Question 9. Who proposed the germplasm concept?

1. Goldsmith
2. Spencer
3. Hugo de Vries
4. Weismann

Answer: 4. Weismann

Question 10. Which one of the following is the intraspecific struggle for the same food? .

1. The struggle between vulture and hyaena
2. The struggle between the eagle and the kite
3. The struggle among the members of rohu fish in the pond
4. Struggle between Egret and Kingfisher

Answer: 3. Struggle among the members of rohu fish in the pond

Life Science Class 10 Wbbse

Question 11. Identify which of the following indicates interspecific struggle—

1. A struggle among the members of guppy fish for feeding on mosquito larvae
2. The struggle between snakes and owl
3. Struggle within a group of deer for feeding on grass at the same location
4. The struggle between tigers in a jungle for preying on deer.

Answer: 2. Struggle between snakes and owl

Question 12. Parthenium is an exotic species in our country. Other indigenous species cannot survive in such places where in grows. This establishes one of the postulates of Darwin’s theory. Identify the postulate—

1. Intraspecific struggle
2. Interspecific struggle
3. Struggle with environment
4. Origin of new species

Answer: 2. Interspecific struggle

Chapter 4 Theories Of Organic Evolution Answer In A Single Word Or Sentence

Question 1. Who is known as the father of evolution?
Answer: Charles Robert Darwin

Question 2. Who proposed the mutation theory?
Answer: Hugo de Vries

Question 3. What is the title of the famous book, authored by Darwin, featuring organic evolution?
Answer: On the Origin of Species by Means of Natural Selection

Question 4. On which ship, did Darwin set off for his tour around the world?
Answer: Darwin set off for a five years long tour (1831-1836) around the world on the ship named HMS (Her Majesty’s Ship) Beagle.

Question 5. Name the island, where Darwin found different types of finches and various other special birds.
Answer: Galapagos island

Question 6. Who proposed the theory of use and disuse?
Answer: Lamarck

Question 7. Which theory did Weismann propose in the year 1892?
Answer: The germplasm theory of evolution

Question 8. What is the name of the struggle, faced by different species, in search of food and shelter?
Answer: Inter-specific struggle

Life Science Class 10 Wbbse

Question 9. According to Darwin, what was the nature of the growth rate of a natural population?
Answer: According to Darwin, any natural population grows at a geometric rate.

Question 10. Name a scientist who advocated Neo- Lamarckism.
Answer: Herbert Spencer

Question 11. What are the main criteria of survival of the fittest?
Answer: Suitable variation and natural section

Question 12. Write down one limitation of Darwinism.
Answer: Darwin can not explain the reason of the formation of variation.

Chapter 4 Theories Of Organic Evolution Fill In The Blanks

Question 1. For food, shelter and mating partners, members of the same species involve in _______ struggle.
Answer: Intra-specific

Question 2. Members of different species involved in _______ struggle for food and shelter.
Answer: Inter-specific

Question 3. Darwin described _______ as the ‘game of nature’.
Answer: Mutation

Question 4. Darwin had put special emphasis on small and unstable _______in the origin of a new species.
Answer: Variation

Question 5. According to _______, any organism in its lifetime is inherited by its successive generations.
Answer: Lamarck

Question 6. _______ opined that, the use and disuse of any organ results in to the physical change of the organ.
Answer: Lamarck

Question 7. _______ was the first to use the term ‘evolution.
Answer: Spencer

Question 8. It is now proven that the inheritance of acquired characters occurs only by_______ cells.
Answer: Germ

Question 9. Darwin observed the structure of the beak of _______ bird.
Answer: Finch

Question 10. Darwin termed the difference between two organisms as_______.
Answer: Variation

Chapter 4 Theories Of Organic Evolution State True Or False

Question 1. Darwin authored the famous book, ‘Origin of Life’.
Answer: False

Question 2. Lamarck proposed the concept of survival of the fittest.
Answer: False

Question 3. According to Lamarck, natural selection is the main driving force for organic evolution.
Answer: False

Question 4. According to Lamarck, the neck of the giraffe is long due to the use of organs.
Answer: True

Life Science Class 10 Wbbse

Question 5. According to Darwin, organisms reproduce at a geometric ratio.
Answer: True

Question 6. The concept of survival of the fittest is proposed by Lamarck.
Answer: False

Question 7. Darwin gives importance to mutation in his theory.
Answer: False

Question 8. Weismann opposed the theory of Lamarck.
Answer: True

Question 9. The fundamental tenet of the evolutionary theory of Darwin is the process of natural selection.
Answer: True

Chapter 4 Theories Of Organic Evolution Match The Columns

1.

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

2.

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

Chapter 4 Theories Of Organic Evolution Find The Odd One Out

Question 1. Law of use and disuse, Law of independent assortment, Theory of natural selection, Law of inheritance of acquired characters
Answer: Law of independent assortment

Question 2. Weismann, Hugo de Vries, Goldsmith, Darwin
Answer: Darwin

Question 3. Herbert Spencer, Charles Darwin, Gregor Johan Mendel, Jean Baptist L’amarck
Answer: Gregor Johan Mendel

Life Science Class 10 Wbbse

Question 4. Lamarkism, Darwinism, Haldane-Oparin hypothesis, Mendelism
Answer: Mendelism

Question 5. Use and disuse of organs, Inheritance of acquired character, Formation of new organs within organisms out of a need
Answer: Natural Selection

Question 6. Natural selection, Struggle for existence, Variation, Use and disuse of an organ
Answer: Use and disuse of an organ

Chapter 4 Theories Of Organic Evolution Fill In The Blanks By Looking At The First Pair

Question 1. Inheritance of acquired characters: Theory of Lamarck:: Survival of the fittest:________
Answer: The theory of Darwin

Question 2. On the Origin of Species by Means of Natural Selection: Charles Darwin:: Philosophie Zoologique: ________
Answer: Jean Baptist Lamarck

Question 3. Lamarckism: Inheritance of acquired characters:: Darwinism: ________
Answer: Natural selection

Life Science Class 10 Wbbse

Question 4. Neo-Lamarckism: Herbert Spencer :: Neo- Darwinism:________
Answer: Hugo de Vries

Chapter 4 Theories Of Organic Evolution Among The Four Concepts Given Three Of Them Belong To One Find That

Question 1. Fighting among members of the same species, Prey-predator interaction, Struggle for existence, Trying to survive against natural calamities
Answer: Struggle for existence

Question 2. Lamarckism, Use and disuse of organs, Inheritance of acquired characters, Formation of organs within organisms from the need
Answer: Lamarckism

Question 3. Drought, Heavy rain, Competition for food, Struggle for Existence
Answer: Struggle for existence

Question 4. HMS Beagle, Natural selection, Darwin, On the Origin of Species by Means of Natural selection
Answer: Darwin

Question 5. Darwinism, Lamarckism, Mutation theory, Evolution theory
Answer: Evolution theory