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Question
With the help of two suitable examples, explain why certain experiences and traits earned by people during their lifetime are not passed on to their next generations. When can such traits be passed on?
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Solution
The experiences and qualifications that a person earns during his/her lifetime are examples of acquired traits. These traits cannot be inherited, as they do not affect genetic make up of an organism. In fact, these traits develop due to use and disuse of organs, or due to direct affect of environment. Thus, they are not passed on to the next generation. For example, a wrestler develops large muscles because of his training programme; it does not mean that his offspring will necessarily have large muscles. Similarly, if a lady pierces her nose, the children produced to her will not have pierced nose by birth.
Traits can be passed on to the next generation only when they have some direct effect on the genes. For example, if a mutation is caused in the germ cells of a person due to exposure to some harmful radiations, it is highly likely that the mutation caused will be passed on to the subsequent generations.
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