Question
Biology Question on evolution
Appetency is the formation of new structure or habit of the organism according to its need. Appetency is also called doctrine of desire.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
If both assertion and reason are true but reason is not the correct explanation of assertion
Solution
According to Lamarck, a change in environment brings about changes in organisms. It gives rise to new needs. New needs or desires produce new structures and change habits of the organisms. Doctrine of desire is called appetency. It can be shown by the following example- Water birds (duck etc.) developed their webbed feet by constant stretching of digits and the skin between them for skimming the water surface and for swimming. The transmission of acquired characters is the most important principle usually termed as the Lamarckian doctrine.