Question

Which one of the following is correct with respect to homologous structures?

• A. Organs with anatomical similarities, but performing different functions
• B. Organs with anatomical dissimilarities, but performing same functions
• C. Organs that have no function now, but had an important function in ancestor
• D. Organs appearing only in embryonic stage and disappearing later in the adult

Answer 1

The correct option is A Organs with anatomical similarities, but performing different functions

Homologous organs are those that are anatomically/structurally similar but functionally different. A typical example would be the forelimbs in man and the flippers in whales. Despite being structurally similar (they are both made up of the same kinds of bones - humerus, radius, ulna, etc.), the forelimbs are meant to perform very different functions in these animals. This has resulted because they both originated from a common ancestor, and during the course of their evolution, according to their needs, the basic structure got modified differently.