Tag: darwin's theory of evolution
Questions Related to darwin's theory of evolution
Lamarckian evolution is correctly characterized by
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Evolutionary change happens instantaneously.
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An animal that draws on a particular trait very often passes that trait on in reduced form to offspring because of overuse.
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The function of a body part plays no part in evolution.
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Acquired traits can be passed down from parent to offspring.
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Selection pressures push evolutionary change.
Lamarck contributed to organic evolution through his theory. According to Lamarck, changes in the environment create new needs in the organism for adaptation. Use and disuse of organs and inheritance of acquired characters was also explained by Lamarck. He explained that certain characters which are acquired by the parents can be passed to the offspring.
A scientist who worked on rats,
cut their tails up to 21 successive generations
but at last he found that tail remained normal. By giving this experimental theory, which of the following scientist got disapproved?
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Darwin
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Lamarck
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Hugo de Vries
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Mendel
This experiment disproves the theory of inheritance of acquired characters, because the tailless condition is an acquired characteristic but it is not inherited by succeeding generations. Lamarck gave theory of inheritance of acquired characters.
The scientists regarded as Neo-Lamarckist are
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August Weismann and T.H. Morgan
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Hardy-Weinberg
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Correns, Tschermak and Hugo de Vries
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Kammerer and McDougall
Kammerer and McDougall respectively worked on toads and rats and tried to gather experimental evidences to prove Lamarckism, but their experiments were not conclusive evidence for Lamarckism and were criticised on several counts.
Key point to Lamarck's view about organic evolution is that every offspring
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Is similar to its parents.
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Inherits characters acquired by the parental generation.
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Shows struggle for existence.
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Repeats phylogeny in its ontogeny.
Lamarck gave the theory of Inheritance of acquired character. According to which characters acquired by an organism during it's life are inherited by the next generation.
The statement, 'Lamarck's acquired
characters are not inherited and have
no evolutionary value' was given by
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Hugo de Vries
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Charles Darwin
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Weismann
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T.H. Morgan
Weismann cut the tails of experimental animals for many generations, yet they were always born with tail. Thus proving that acquired characters (tailless state in this case) are not inherited.
Most popular example of Lamarck is
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African Giraffe
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Snake
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Primose
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Both A and B
Lamarck theory is also called as Lamarckism. The most popular example used to explain the concept of Lamarckism is the elongated neck of the giraffe. According to this theory, an elongated neck of an African giraffe evolved to reach leaves high in trees. In another example, he proposed that water birds gained long webbed toes for better swimming. Another example of Lamarckism is snakes whose ancestors are lizard like reptiles. They acquired elongated limbless body for their protection.
Germplasm theory against Lamarck's principle, was given by
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Weismann
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Darwin
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Lamarck
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Hugo de Vries
According to Lamark's principle all the characters that are acquired during the lifetime of an organism are passed on to the next generation. This theory is called as inheritance of acquired characters. However, Wiesmann did not agree with this theory, and proved through the tail cutting experiments on mice that only the changes that take place in the germ cells or the gametes are only passed on to the next generation.
Who proved that somatic cells have little influence in inheritance?
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Lamarck
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Darwin
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Weismann
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Cuvier
The answer is option C i.e. "Weismann".
- Weismann gave the germ plasm theory which proved that somatic cells have little or no influence in inheritance.
- Darwin only supported Weismann that one’s acquired character is not inherited in the next generation.
- Lamarck gave a hypothesis on the inheritance of acquired characteristics, he proposed the idea of heritability of acquired characteristics.
- While Cuvier did not work in the discovery of inheritance. He discovered the process of the formation of fossils.
Living beings are made up of cells. This was first stated by
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Lamarck
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Von Helmont
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Schleiden and Schwann
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Hugo de Vries
Lamarck is best known for his 'Theory of Inheritance' of Acquired Characteristics. If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring.
Theory of inheritance of acquired characters was given by,
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Wallace
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Lamarck
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Darwin
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De Vries
The first theory of evolution was proposed by Jean Baptiste de Lamarck Lamarckism proposed,
- Some internal forces are present in all organisms. Due to the presence of these forces, the organism has the tendency to increase the size of their organs or the entire body.
- Environment influences all type of organisms. Changing environment give rise to new needs. New needs or desires produce new structure and change habits of the organism.
- If an organ is constantly used, it would be better developed whereas disuse of organ results in its degeneration.
So, the correct option is 'Lamarck'