into the testicular network where they travel to the epididymis. The epididymis is
located outside of the testis (see figures 1-8 and 1-9).
Figure 1-9. Structure of the testes.
b. Duct System. The duct system is the passageway for the sperm to exit the
body. It contains the epididymis and the vas deferens.
(1) Epididymis. The epididymis is a coiled tube about 20 inches long. It
caps the superior part of the testis and runs down its posterior side. It forms the first
part of the duct system and provides a temporary storage site for immature sperm.
When the male is sexually stimulated, the walls of the epididymis contract to expel
sperm into the next part of the duct system.
(2) Vas deferens (ductus deferens). The sperm continue their journey
through the vas deferens. The vas deferens runs upwards from the epididymis through
the inguinal canal into the pelvic cavity and arches over the bladder (see figure 1-8). It
is enclosed with blood vessels and nerves in a connective tissue sheath, which is called
a spermatic cord. The vas deferens empties into the ejaculatory duct that carries the
sperm through the process to empty into the urethra.
c. Accessory Glandular Structure. The accessory glandular structure
includes the seminal vesicles, prostate gland, Cowper's glands, and the penis.
(1) Seminal vesicles. The two seminal vesicles are pouches that store
sperm. Sixty percent of fluid volume of semen (seminal fluid) is produced there. The
secretion is rich in sugar (fructose), which nourishes and activates the sperm passing
through the tract.
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