Page 68 - 86 human physiology part-2

The Male Reproductive System

as well as make the adluminal compartment an immune-privileged site.

During the time of sperm maturation, large sertoli cells nourish the immature sperm and filter out
harmful things before they reach the sperm. In these ways, they assist the sperm to mature. They are
support cells that form a blood barrier with the blood. They filter what comes to sperm cells.

The cell is also responsible for establishing and maintaining the spermatogonial stem cell niche,
which ensures the renewal of stem cells and the differentiation of spermatogonia into mature germ cells
that progress stepwise through the long process of spermatogenesis, ending in the release of
spermatozoa.

Other functions During the Maturation phase of spermiogenesis, the Sertoli cells consume the
unneeded portions of the spermatazoa.

Efferent ductules

The sperm are transported out of the testis and into the epididymis through a series of efferent
ductules.

Blood Supply

The testes receive blood through the testicular arteries (gonadal artery). Venous blood is drained
by the testicular veins. The right testicular vein drains directly into the inferior vena cava. The left
testicular vein drains into the left renal vein.

Epididymis

The seminiferous tubules join together to become the epididymis. The epididymis is a tube that is
about 20 feet long that is coiled on the posterior surface of each testis. Within the epididymis the sperm
complete their maturation and their flagella become functional. This is also a site to store sperm until
the next ejaculation. Smooth muscle in the wall of the epididymis propels the sperm into the ductus
deferens.

Ductus Deferens

The ductus (vas) deferens, also called sperm duct, or, spermatic deferens, extends from the
epididymis in the scrotum on its own side into the abdominal cavity through the inguinal canal. The
inguinal canal is an opening in the abdominal wall for the spermatic cord (a connective tissue sheath
that contains the ductus deferens, testicular blood vessels, and nerves. The smooth muscle layer of the
ductus deferens contracts in waves of peristalsis during ejaculation.

Seminal Vesicles

The pair of seminal vesicles are posterior to the urinary bladder. They secrete fructose to provide
an energy source for sperm and alkalinity to enhance sperm mobility. The duct of each seminal vesicle
joins the ductus deferens on that side to form the ejaculatory duct.

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