Question

In rabbit, the head of epididymis present at the head of the testis is called as-
A. Caput epididymis
B. Cauda epididymis
C. Vas deferens
D. Gubernaculum

Answer 1

In mammals the extra-testicular duct system consists of tubes which conduct sperms from the testes to the outside. It starts with the duct known as vasa efferentia. From each testis, 10-12 vasa efferentia confluent to form a folded and coiled tube called epididymis behind each testis.

Complete answer:
The epididymis connects testes to vas deferens. It is a single, tightly coiled tubule. It consists of three parts-

Caput-above the testes
Corpus-middle of testes
Cauda-below the testes
Main function of epididymis include-
Storage of sperms, temporarily.
Sperms attain motility and maturity here.
Decapacitation of sperms.
Sperms entering the caput lack the ability to swim forward and to fertilize an egg. Epididymis stores sperm for 2-3 months. Sperms undergo maturation process and the final maturation occurs in Female reproductive tract that is called capacitation.
Epididymis secrete some proteins which block the receptors on the plasma membrane of the sperm head, which renders sperm to be infertile in the male reproductive tract which Is known as Decapacitation.
Cells of sperms have stereocilia (microvilli) to increase the surface area for absorption of shed off part of sperms during its maturation.

The head of epididymis present at the head of the testes in case of rabbit is Caput epididymis.

Note: Decapacitation- Coat of cholesterol and glycoprotein are provided over sperm so that its membrane is prevented from rupturing during its journey from seminiferous tubule to epididymis.
Capacitation- Removal of the layers of cholesterol and glycoprotein from the sperm head occurs in the female reproductive tract.
Gubernaculum-A fibrous cord extending from caudal of the testes to the scrotal wall. It keeps the testes bound to the scrotal sac.