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प्रश्न
Explain the occurrence of vestigial organs on the basis of Lamarck's theory of use and disuse.
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उत्तर
Organs which are found in reduced or rudimentary condition and do not perform any function in the possessor are called vestigial organs or non-functional organs. They help in understanding the history of evolution and continuity of life.
- Wisdom teeth: They are the last molars which appear last at the age of 17-20 years.
- Vermiform appendix: It projects from the blind end of the caecum and is a functionless organ in humans. It is helpful in herbivorous mammals.
- Pinna: It is the lobe-like part of the external ear which humans cannot move as in other mammals. As it is poorly developed, it is a vestigial organ.
संबंधित प्रश्न
Write a short note based on the information known to you.
Lamarckism
Survival of fittest : Darwin : : Acquired characters : ..............................
The first scientist who proposed his theory for evolution was ______.
Observe the picture and answer the following questions.
- The given picture indicates which principle?
- Explain that principle in your language.
- What is the meaning of acquired characteristics?
The degenerated wing of a kiwi is an acquired character. Why is it an acquired character?
In which work and year was Lamarck's theory of evolution published?
According to the postulate on the 'Formation of New Organs', a new organ develops in response to which factor?
Under the postulate of 'Inheritance of Acquired Characters', how are traits or modifications acquired during an organism's lifetime transmitted to its offspring?
For an acquired trait to be transmitted to the next generation, which of the following cell types would need to be altered?
A newborn rat in Weismann's experiment was born with a normal tail even though its parents' tails had been cut off. This outcome directly contradicts which postulate of Lamarckism?
