Male Reproductive System & Meiosis – Vocabulary Flashcards

A set of vocabulary flashcards covering key terms related to male reproductive anatomy, spermatogenesis, hormonal regulation, and meiosis.

Gamete

A reproductive cell with half the usual chromosomes (sperm in males, oocyte in females), made by meiosis.

Spermatogenesis

The whole process of making sperm in the seminiferous tubules, including cell division, meiosis, and final shaping.

Spermiogenesis

The final step where an immature sperm cell (spermatid) changes into a mature sperm (spermatozoon), getting rid of extra parts and forming its tail.

Capacitation

The process after ejaculation where sperm become fully able to fertilize an egg, happening in seminal fluid and the female reproductive tract.

Seminiferous Tubule

A tightly coiled tube in the testes where sperm are made.

Sertoli (Nurse) Cell

Support cells in the seminiferous tubules that create a protective barrier (blood-testis barrier) and release hormones like inhibin, ABP, and MIF.

Leydig (Interstitial) Cell

Cells in the testes that make testosterone when stimulated by LH.

Gonadotropin-Releasing Hormone (GnRH)

A hormone from the hypothalamus that tells the pituitary gland to release FSH and LH.

Luteinizing Hormone (LH)

A hormone from the pituitary gland that makes Leydig cells produce testosterone.

Follicle-Stimulating Hormone (FSH)

A pituitary hormone that helps Sertoli cells support sperm production and release inhibin and ABP.

Inhibin

A hormone from Sertoli cells that tells the pituitary to make less FSH (and possibly GnRH).

Androgen-Binding Protein (ABP)

A protein from Sertoli cells that keeps testosterone levels high in the seminiferous tubules to help sperm mature.

Müllerian-Inhibiting Factor (MIF)

A hormone from Sertoli cells that causes the breakdown of Müllerian ducts in developing embryos.

Tunica Vaginalis

A protective outer layer covering the testes, like a sac, that comes from the abdominal lining.

Tunica Albuginea

The tough, white outer capsule of the testis that forms internal compartments (lobules).

Dartos Muscle

A smooth muscle in the scrotum that wrinkles the skin to control the temperature of the testes.

Cremaster Muscle

A skeletal muscle that raises or lowers the testes to help regulate their temperature.

Spermatic Cord

A cord containing the ductus deferens, blood vessels, nerves, and lymphatic vessels for the testes, passing through the groin.

Epididymis

A coiled tube on top of the testis where sperm develop more, are stored, and old sperm are broken down.

Ductus (Vas) Deferens

A muscular tube that carries sperm from the epididymis to the ejaculatory duct using wave-like contractions.

Ejaculatory Duct

A short tube formed where the ductus deferens joins the seminal vesicle, which then empties into the urethra.

Seminal Vesicle

A gland that makes about \sim 60\% of semen, containing sugar (fructose) for energy, prostaglandins, and fibrinogen; its fluid is alkaline.

Prostate Gland

A gland that adds about \sim 30\% of semen; it produces a thin, milky fluid that is alkaline and contains enzymes that help semen clot and then liquefy.

Bulbourethral (Cowper’s) Gland

Two glands that release thick, alkaline mucus into the urethra just before ejaculation, to clean and lubricate it.

Corpora Cavernosa

The two main erectile tissues in the penis that fill with blood to cause an erection.

Corpus Spongiosum

The single erectile tissue in the penis that surrounds the urethra and forms the head of the penis (glans penis).

Glans Penis

The expanded, sensitive tip of the penis.

Prepuce (Foreskin)

The loose skin fold covering the glans penis; it's removed during circumcision.

Meiosis

A two-step cell division that creates four genetically different cells (gametes) with half the usual number of chromosomes, from one parent cell.

Mitosis

A single cell division that creates two identical cells, used for growth and repair.

Crossing-Over

The exchange of genetic material between similar chromosomes during the first stage of meiosis.

Independent Assortment

The random way pairs of chromosomes line up during meiosis, which creates genetic variety.

Haploid (1n)

A cell containing a single set of chromosomes (23 in humans).

Diploid (2n)

A cell containing two complete sets of chromosomes (46 in humans).

Blood–Testis Barrier

A protective barrier formed by Sertoli cells that separates developing sperm cells from the body's immune system.

Seminal Fluid

The alkaline fluid from accessory glands that carries sperm, providing nutrients, pH buffers, and enzymes.

Seminal Plasmin

An antibiotic enzyme from the prostate gland in semen that might prevent urinary infections.

Fibrinolysin

An enzyme from the prostate that breaks down semen clots after ejaculation.

Testosterone

The main male hormone involved in sperm production, male characteristics, sex drive, and building muscle.

Negative Feedback (Hormonal)

A control system where high levels of a hormone (like testosterone or inhibin) tell the body to reduce the release of hormones that stimulate it (like GnRH or FSH).

Puberty (Male)

The stage when a male's body starts to mature sexually: GnRH increases, leading to higher FSH/LH and testosterone, and reproductive ability begins.