The testicles

The testicles are two oval glands that sit behind the penis in a pouch of skin called the scrotum. They are part of the male reproductive system and are also called testes (or a testis, if referring to one).

Role of the testicles – The testicles produce and store sperm. They also produce the sex hormone testosterone, which is responsible for the development of male characteristics, such as facial hair, a deeper voice and increased muscle mass, as well as sexual drive (libido).

Epididymis, spermatic cord and vas deferens – A tightly coiled tube at the back of each testicle called the epididymis stores immature sperm. The epididymis connects the testicle to the spermatic cord. The spermatic cord runs through the groin region into the pelvis and contains blood vessels, nerves, lymph vessels and a tube called the vas deferens. The vas deferens carries sperm from the epididymis to the prostate gland.

Seminal vesicles and prostate gland – Two small glands called seminal vesicles sit above the prostate gland. The seminal vesicles and prostate gland produce fluids that make up a large part of semen. Semen also contains sperm from the testicles and is ejaculated from the penis during sexual climax.

Lymph nodes and vessels – There are many lymph nodes (also called lymph glands) and lymph vessels around the testicles and in the abdomen. These are part of the lymphatic system and are important for resisting and fighting disease (immunity). The nodes and vessels also drain lymphatic fluid (lymph) from the tissues back into the bloodstream.

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