On this section of epididymis, and in the image at the right, identify the efferent ducts with their characteristic saw tooth or scalloped appearance due to the presence of tall columnar ciliated epithelial cells interspersed with simple cuboidal cells. The efferent ducts absorb most of the fluid produced by the seminiferous tubules and convey the sperm into the epididymis via contraction of the smooth muscle surrounding the ducts.

The epididymis is a long convoluted duct with smooth muscle in its wall. Examine the images below and the beginning or head of the epididymis adjacent to the efferent ductules and the tail of the epididymis (leading to the vas deferens). Identify the tall columnar, pseudostratified epithelium with stereocilia and the stored spermatozoa in the lumen. The epididymis functions to promote maturation of the sperm, providing factors that decapacitate them (prevent their fertilizing ability) and allow them to become fully motile. The epididymis also stores the spermatozoa and propels them into the ductus deferens during ejaculation.

The ductus deferens or vas deferens is a muscular tube that leads from the epididymis to the prostate gland and functions to rapidly propel sperm during ejaculation.

• Examine the images below and these specimens of ductus deferens (sample 1, sample 2). At higher magnification, identify the pseudostratified columnar epithelium with sparse stereocilia, fibroelastic lamina propria, and three thick layers of smooth muscle (organized as inner longitudinal (IL), middle circular (MC), and outer longitudinal (OL) layers) that allow for rapid, peristaltic expulsion of sperm from the epididymis. In sample 2, note the arteries, veins, and nerves embedded in loose connective tissue that travel with the ductus deferens in the spermatic cord.