Question

In earthworm, the process of spermatogenesis takes place in
A. Spermatheca
B. Testis
C. Testis sac
D. Seminal vesicle

Answer 1

Hint: Earthworms are recognized as farmers’ friends. They possess a cylindrical structure metamerically segmented body. They are reddish-brown in colour.

Complete Answer:
Let us analyse the given options to find out the correct answer.
- Option A: Spermatheca is also understood as seminal receptacles as they conserve sperms from another earthworm during intercourse. This is an incorrect option.
- Option B: There are two sets of testes, which are arranged in the $10^{th}$ and $11^{th}$ portions on each side of the alimentary canal. The germinal epithelium of the testis provides increase to the sperm cells by spermatogenesis. This is the correct option.
- Option C: Testes are existing within fluid-filled sacs named testis sacs. This is an incorrect option.
- Option D: Two pairs, existing on the $11^{th}$ and $12^{th}$ segment. Each seminal vesicle is attached to the testis sac. Spermatogonia cells expire from testis sacs to seminal vesicles, where they evolve to shape spermatozoa. This is an incorrect option.

Thus, option B is the correct answer.

Additional Information: Earthworms are normally seen in soil, consuming a wide mixture of organic matter. This organic substance comprises plant matter, living protozoa, nematodes, bacteria, and other microbes. An earthworm's digestive tract rides the distance of its body. It respires by its skin. It has a dual conveyance system generated of coelomic fluid that stirs within the fluid-filled coelom and a similar closed circulatory network.

Note: Earthworms are monoecious i.e. they include both male and female reproductive parts. Reproduction is primarily by cross-fertilization in earthworms. Reproductive components are existing on 9th to 15th segments.