Question

The functional unit of the testis of man is

• A. Uriniferous tubules
• B. Malpighian tubules
• C. Seminiferous tubules
• D. Acini or lobules

Answer 1

The correct option is C Seminiferous tubules

Each test is oval-shaped measuring 4.5 cm long, 2.5 cm wide in adult. It is enclosed in fibrous sac called as tunica albuginea. The sac extends into a testes to divide the testes into lobules. Next to tunica albuginea is tunica vaginals which is a continuation of membrane of abdomino-pelvic cavity.

Each test contain 800 lightly coiled seminiferous tubules (functional unit of testis), which produce thousands of sperm each second.

The walls of the semniferous tubes are lined with germinal tissue. The germinal tissue contains two types of cells - spermatogenetic cell producing or developing the sperm cell and the sustentacular cell which provide nourishment for the germinal sperm. Between the seminiferous tubules clusters of endocrine cells, called as interstitial endocrinocytes (Leydig cell) secrete male sex hormone (Androgens), where testosterone is the most important.