Male Reproductive Vocab

Scrotum

Skin-covered muscular sac that extends from the body and encloses the testes, controlling temperature for sperm development

Dartos muscle

Smooth muscle that gives the scrotum a wrinkled appearance; contracts in cold (decreases skin surface area) and relaxes in heat

Cremaster muscle

Muscle in the scrotum that reflexively contracts to elevate the testes in cold or relaxes to lower the testes in heat

Spermatic cord

Bundle of fibers and tissues that run through the abdominal region down to each testicle to provide blood flow, lymphatic drainage, and a conduit for the vas deferens

Pampiniform plexus

Network of small veins in the spermatic cord that surround the testicular artery and cool the blood before it reaches the testes; plays a crucial role in testicular thermoregulation

Tunica vaginalis

Outer serous membrane of the testes

Tunica albuginea

Tough, white, dense connective tissue layer covering the testes that forms septa in them to divide them into lobules

Sertoli/nurse cells

Large, branching support cells that secrete signaling molecules to promote sperm production, create the blood-testis barrier, digests excess cytoplasm of developing sperm cells, and secretes testicular fluid into the lumen of the seminiferous tubule

Blood-testis barrier

Physical barrier created via tight junctions of Sertoli cells that prevents bloodborne substances from reaching germ cells and prevents germ cells from reaching the blood and prompting an immune response

Seminiferous tubule

Developing sperm cells around a lumen that comprise the bulk of each testis

Straight tubule

Where seminiferous tubules empty

Rete testes

Fine meshwork of tubules that straight tubules empty into

Efferent ductules

Tubes that bring testicular fluid from the rete testes to the epididymis

Leydig cell

Cell in the interstitial tissues between seminiferous tubules that produce testosterone

Gubernaculum

Connective tissue fiber that contracts to move the testes through the inguinal canal to the scrotum at around month 7 of fetal development

Cryptorchidism

Condition where one or both testes fail to descend into the scrotum prior to birth; testes will not produce sperm and this condition increases the risk of testicular cancer if not surgically treated

Spermatogonia

Germ/stem cells of the testes that line the basement membrane inside seminiferous tubules

Spermatogenesis

Process that turns spermatogonia into mature sperm cells

Epididymis

Highly coiled tube next to the testes where immotile sperm mature and are stored until ejaculation

Acrosome

Cap that covers most of the head of a sperm cell and is filled with lysosomal enzymes important for breaking apart the female egg during fertilization

Ductus/vas deferens

Thick, muscular tube in the spermatic cord that brings sperm from the epididymis up to the abdominal cavity and then to the ejaculatory duct