A scientist who worked on rats cut their tails upto 21 successive generations but at last he formed that tail remained normal. By this experiment theory of which scientist is disapproved

Options

A. Darwin
B. Lamarck
C. Hogo de Vries
D. Mendal

Answer

**Step-by-Step Solution:**

1. **Identify the Experiment**: The scientist conducted an experiment on rats where he cut their tails for 21 successive generations.

2. **Observe the Outcome**: After 21 generations of cutting the tails, the tails of the rats returned to a normal state, indicating that the trait of having a tail was not affected by the previous generations of tail cutting.

3. **Understand the Theories**:
- **August Weismann's Theory**: Weismann proposed the theory of germplasm, which states that only changes in the germ cells (reproductive cells) can be inherited by the next generation. Changes in somatic cells (body cells) do not affect inheritance.
- **Lamarck's Theory**: Lamarck proposed the theory of inheritance of acquired characteristics, suggesting that traits acquired during an organism's lifetime can be passed on to the next generation.

4. **Analyze the Results**: The results of the experiment (normal tails after 21 generations) support Weismann's theory because it shows that the acquired characteristic (tail cutting) did not get inherited. This contradicts Lamarck's theory, which would suggest that the rats should have inherited the trait of having shorter tails.

5. **Conclusion**: The experiment disapproves of Lamarck's theory of inheritance of acquired characteristics, as it demonstrates that traits acquired during an organism's lifetime (like tail cutting) are not passed on to future generations.

**Final Answer**: The experiment disapproves the theory of Lamarck regarding the inheritance of acquired characteristics.

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