Question

Weismann cut the tail of mice for
A. 12 generations
B. 18 generations
C. 22 generations
D. 28 generations

Answer 1

Hint: Weisman through the experiment of cutting tails of mice for generations showed that Lamarck’s theory of inheritance of acquired characters was wrong.

Complete Answer:
Let’s look into Weismann’s experiment.
- Weismann proposed the theory of continuity of germplasm where he said the germplasm (protoplasm of germ cells) is inherited and the somatoplasm is not transmitted to the next generation.
- For example the muscle of a wrestler doesn’t get transmitted to his kids because it is an acquired character by him which causes changes in his somatic cells only.
- Weismann proved this theory by performing an experiment in which he cut off the tail of mice for 22 generations and allowed them to breed. Every offspring was born with a tail, never once a tailless mouse was born.
- Because cutting off the tail was a trait that the mice acquired during its lifetime and has nothing to do with the germ cells of the mice. Therefore the trait was not inherited to the next generation.

Thus, the correct answer is option C: 22 generations.

Additional information: Lamarck’s theory stated that the characters acquired by use or disuse or habit will be passed on to the next generation. He claimed the long neck of a giraffe as an example of the same. This was disproved by Weismann’s experiment.

Note: The number of generations for which Weismann cut the tail doesn’t bring a difference to the result of the experiment. Even if we cut the tail of mice for less than or more than 22 generations, the result will be consistent.