Question

Assertion (A): According to Lamarck, the environment is under frequent changes which create new needs in an organism.
Reason (R): These needs force the organism to use some organs more frequently and some organs less frequently (use and disuse of organs).

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true but R is not the correct explanation of A
• C. A is true but R is false
• D. A is false but R is true

Answer 1

The correct option is A Both A and R are true and R is the correct explanation of A

Lamarckism is based on three main ideas:- new needs, use and disuse of organs, inheritance of acquired characters.
New needs are created in organisms due to the ever changing environment. If the organism fails to make the favourable changes, it won't survive. These new needs will force the organism to use organs more/less frequently. The parts which are used more will become stronger whereas the least used ones will eventually disappear. The overuse and disuse of organs would change the organism to some extent and they will acquire new characters, which Lamarck believed would get transfered to future generations.