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प्रश्न
Briefly discuss Lamarckian Theory of Inheritance citing an appropriate example.
उत्तर
- According to the theory of inheritance of acquired characters, 'the changes in structure or function of any organ acquired during the life-time of an individual in response to changes in the surrounding environment are inherited by offspring and keep on adding over a period of time'.
- This theory states that characters are acquired by animals in two ways:
- Effects of environment
- Use and disuse of body parts
- For example, the long neck of giraffe is explained by Lamarck on the same principle. Giraffe, which lived in the dry and arid deserts of Africa, tried to reach the foliage high up on the trees to eat them as there was no vegetation on the ground. In the process, its neck and forelegs got stretched a bit and this was inherited by the next generation. Then, in the next generation, the same efforts continued. Gradually, through many successive generations, we got a giraffe having a long neck and long forelegs.
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संबंधित प्रश्न
Write short notes based upon the information known to you.
Lamarckism
a) Explain in brief - Lamarck’s principle of ‘use or disuse of organs’.
b) Give two examples.
c) What are ‘acquired characters’?
Mention the two principles through which Lamarck explained his ideas.
What is inheritance of acquired characters?
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 ‘use and disuse theory’ was proposed by ______.
The use and disuse theory of organs’ was postulated by Charles Darwin.
The degenerated wing of a kiwi is an acquired character. Why is it an acquired character?
Observe the following figure and explain the concept.
The theory proposed by Lamarck is ______.