Question

Q. The diagram shown below is the longitudinal section of the testis of man. Study it carefully and answer the questions that follow-

1. Label the parts numbered 1 to 3 in the diagram.
2. In which part of the testis, are the sperms produced?
3. State the functions of the parts labeled 1 and 3 in the diagram?

Answer 1

1) Labeling the diagram:

1. The scrotum is a chamber made of loose skin present in between the thighs and hangs down from the abdomen that houses the testes. It helps in thermoregulation thereby supporting the development of sperms.
2. The sperm duct or Vas deferens is a thick long muscular tube that receives secretions from the epididymis. It starts from the epididymis and ends at the urethra.
3. The epididymis is a highly coiled tube present above the testis. It temporarily stores the sperms and exhibits peristalsis.

2) Site of sperm production:

1. Sperms are the male gametes that on fertilization with ova in the female reproductive tract are capable of giving rise to an embryo.
2. Sperms are produced in the testes in the seminiferous tubules which consist of germinal epithelium.

3) Functions of parts 1 and 3:

1. The scrotum (part-1) is a chamber made of loose skin present in between the thighs and hangs down from the abdomen. It consists of the testes.
2. It helps in thermoregulation by maintaining the temperature two degrees lower than the body temperature.
3. This helps in maintaining a proper environment for the production of sperms.
4. The epididymis (part-3) is a highly coiled tube present above the testis. It temporarily stores the sperms and exhibits peristalsis.