Testis, ductus deferens, and seminal vesicle histology

Testes, or testis when singular, is responsible for the production of sperm, which is called spermatogenesis.

The testes also produce sex hormones, mainly testosterone.

The male genital ducts carry spermatozoa and liquid from the seminiferous tubules in the testes all the way to the penis.

The genital ducts can be split into two groups, the excretory genital ducts and intratesticular ducts.

The intratesticular ducts include the straight tubules (or tubuli recti), rete testis, and efferent ductules.

And the excretory gential ducts include the epididymis, ductus (or vas) deferens, and urethra.

This very low power image is a sagittal section of a testis, which also includes the head of the epididymis located posterior and partially superior to the testis.

The epididymis is a single, long convoluted duct where spermatozoa accumulate and continue to mature even further, including the development of motility.

Accessory glands, such as the seminal vesicles and prostate gland, secrete seminal fluid that provides lubrication and nutrients for the spermatozoa.

The seminal fluid is also slightly alkaline, or basic.

This alkalinity helps protect sperm and prolong their life after they’ve been deposited in the acidic environment of the vagina.

Surrounding each testis is a thick capsule of connective tissue, called the tunica albuginea.

The connective tissue extends inward from the posterior side of the testes and separates the seminiferous tubules into about 250 incomplete pyramid-shaped lobes.

Each lobe contains one to four highly-coiled seminiferous tubules.

Now, if we zoom in all the way to 40x magnification, we can see the individual seminiferous tubules, which have a germinal epithelium that’s responsible for spermatogenesis.