Question

Weismann cut off the tails of mice generation after generation, but tails neither disappeared nor shortened, proving that ___ .

• A. Darwin was correct
• B. tail is an essential organ
• C. mutation theory was wrong
• D. Lamarckism was wrong about inheritance of acquired characteristics

Answer 1

The correct option is D Lamarckism was wrong about inheritance of acquired characteristics

Lamarckism explained the inheritance of acquired characteristics, and stated that an individual acquires characteristics during its life time due to internal vital forces, effects of environment, new needs, and use and disuse of organs, and these are inherited by the successive generations. After several generations, the variations are accumulated to such an extent that they could give rise to new species. This theory was proved wrong by August Weismann, who put forth the theory of continuity of germplasm. According to this, only the characters influencing the germ cells get inherited. There occurs continuity or inheritance of germplasm (protoplasm of germ cells), but the somatoplasm (protoplasm of somatic cells) is not transmitted to the offspring and hence, it cannot pass on characters to the next generation. Weismann proved this by cutting off the tails of mice for as many as 22 generations, and allowing them to breed. He observed that tailless mice were never born.