Question

Tendrils of Cucurbita and thorns of Bougainvillea are
A. Homologous organs
B. Analogous organ
C. Vestigial organs
D. Atavistic divergence

Answer 1

Hint: Those organs which have similar structure, morphology and anatomy but not similar in function are called homologous organs. It involves the evolution of living individuals in distinct directions but belongs from similar ancestry.

Complete answer:
 Examples of these organs are those who’s not similar in function but similar in their anatomy and morphology. Tendrils of Cocurbita and thorns of Bougainvillea are homologous organs because they are similar in origin as they are modified branches and axial in position. Their different function is modified for protection and in Cucurbita, tendrils are for climbing.
In this structure animals are the same but the function is different. The dorsal fins are used for swimming, the forelimbs of frogs are used for jumping and propping and the forelimbs of man are used for writing, eating, etc.
In option (B) Analogous organs are defined as the organs of different animals that are having different structures but perform the same functions. Example of an analogous organ is the wings of the insect and the wings of the bird.so this option is not an example of Bougainvillea and tendril of Cucurbita.
In option (C) These ‘useless’ body-parts, otherwise known as vestigial organs, are remnants of lost functions that our ancestors possessed. this option is not correct
In option (D) Atavistic divergence genetic traits reappear after loss in evolutionary change for example people in modern times are reverting to the way of thinking and acting.

Hence, the correct answer is option (A).

Note: Homologous organs are modified in branches and their axillary in position axillary benches in bougainvillea is modified into thorns for protection from burrowing animals in Cucurbita into tendrils for climbing. Another Example of homologous organs are the forelimbs of frogs, man, and the flippers of the whale.