Question

A vestigial organ in man is
A. Mammary gland
B. Pelvic girdle
C. Vermiform appendix
D. Sebaceous glands

Answer 1

Hint: Structural features of organisms provide evolutionary relationships among them in the form of homology, analogy, vestigial organs and atavism.

Complete answer:
-Mammary gland
It is an important characteristic feature of mammals. It is an exocrine gland in them that produces milk for feeding their young ones.
Mammary glands are modified sudoriferous glands. They lie over the pectoral major muscle and are attached to them by a layer of deep fascia composed of dense irregular connective tissue. So these are functional organs in mammals.

-Pelvic girdle
It is composed of three bones- ilium, ischium and pubis and forms the hip bone. It helps in connecting the pelvis region of the spine with the lower limbs. So it is also functional in humans.
Sebaceous glands
It is an exocrine gland in humans that opens into hair follicles and secretes sebum which is an oily or waxy material.

-Vestigial organs
These are the organs that were once functional in the ancestral form but later become non-functional.
Presence of structure in an animal indicates its origin from the stock where it was functional.
For example- vestiges of the hind limb and pelvic girdle in python, splint bones in the horse.
Man has more than a hundred vestigial organs like a wisdom tooth, vermiform appendix, coccyx, body hair, pinna muscle, nictitating membrane, etc.
So among the given options in the question, the vermiform appendix is an example of vestigial organ.

So, the correct answer is “Option C”.

Note: Vestigial organs are evidence indicating that modern diverse forms of organisms have arisen by evolution from more ancient forms.