no testosterone is produced during childhood. Resumption of testosterone production
at the onset of puberty stimulates growth and maturation of the male's reproductive
structures and secondary sex characteristics. Testosterone is the male sex hormone
secreted by the interstitial cells of the testes.
Figure 1-8. The male reproductive organs.
b. The primary function of the male's reproduction system is to produce male
sex cells, which are called sperm cells. The primary organs of the male's reproduction
system are the two testes in which the sperm cells are formed. The other structures are
the duct system and the accessory glandular structure.
1-10. MALE REPRODUCTIVE ORGANS
a. Testes (Two). The testes are two almond-shaped glands whose functions are
for the production of sperm and testosterone. The testes are suspended in the scrotal
sac outside the abdominopelvic cavity. It is believed that the testes lie outside the body
cavity because they are very sensitive to heat and the higher temperature within the
body is unfavorable to the production of sperm. Each testis is enclosed by a tough,
white fibrous capsule called the tunica albuginea. Extension of the capsule divides it
into a large number of lobes. Each lobe contains four tightly coiled seminiferous tubules
(this is the location of actual sperm production). The seminiferous tubules empty sperm