Question

Sweet potato and potato tubers

Answer 1

Homologous organs are those which have common origin, similar structure but perform different functions. Analogous structures include those organs that have different origins and different structures but apparently appear similar as they perform similar functions.

Tubers of potato and sweet potato are analogous organs because the tuber of a potato is a modified stem (possess nodes and internodes) and sweet potato is a modified root (do not possess nodes and internodes). Each of them are modifications of different plant parts which have very different basic structures. However, they perform the same function, that is, food storage. They do not perform photosynthesis as they lack chlorophyll and grow beneath the ground.


Living fossils are organisms that have remained unchanged from earlier geologic times (resembling ancestral species) and their close relatives are usually extinct. Example: Horseshoe crab (Limulus).

Vestigial organs are those organs which are present in reduced form and do not perform any function in the body. Example: Vermiform appendix in humans.

Hence, option b is correct and a, c and d are wrong.