32 Male Reproductive System

Flashcards for Male Reproductive System Lecture

Testes

Produce sperm and secrete androgen hormones.

Seminiferous Tubules

Site of sperm production in the testes.

Spermatogenic cells

Sperm forming cells found in the seminiferous tubules.

Sustentacular cells

Cells in seminiferous tubules that produce testicular fluid and nutrients for sperm.

Interstitial Cells (Leydig Cells)

Cells located between seminiferous tubules that produce and secrete androgens, primarily testosterone.

Myoid Cells

Muscle-like cells surrounding seminiferous tubules that contract to push sperm and fluid through the tubules.

Rete Testis

Network of tubules on the posterior testis that sperm pass through.

Epididymis

Duct where sperm mature and are stored for several months.

Ductus Deferens

Tube that extends from the epididymis and transports sperm.

Spermatic cord

Contains the ductus deferens, arteries, veins, and nerves.

Ejaculatory Duct

Formed by the junction of the ampulla of the ductus deferens and the duct of the seminal vesicle; empties into the urethra.

Urethra

Tube that connects the urinary bladder to the external body surface and transports both urine and semen in males.

Penis

Male copulatory organ that delivers sperm into the female reproductive tract.

Accessory Sex Glands

Produce the liquid portion of semen, including seminal vesicles, prostate gland, and bulbourethral glands.

Seminal Vesicles

Paired glands on the posterior surface of the urinary bladder that secrete seminal fluid, contributing 60-70% of semen volume.

Prostate Gland

Gland inferior to the urinary bladder that surrounds the urethra and ejaculatory ducts, contributing 20-30% of semen volume with milky, alkaline secretions.

Bulbourethral Glands

Glands at the base of the penis on either side of the membranous urethra that secrete a thick alkaline mucus-like fluid to neutralize acidic urine and lubricate the urethra.

Semen

Milky white mixture of sperm and fluids from the testes, seminal vesicles, prostate, and bulbourethral glands.

Spermatogenesis

Process of sperm development that begins at puberty in the seminiferous tubules.

Spermatogonia

Diploid stem cells found along the basement membrane of seminiferous tubules that divide by mitosis.

Primary Spermatocytes

Diploid cells that result from the differentiation of spermatogonia and undergo meiosis I.

Secondary Spermatocytes

Haploid cells that result from meiosis I of primary spermatocytes and undergo meiosis II.

Spermatids

Haploid cells that result from meiosis II of secondary spermatocytes and undergo spermiogenesis to become sperm cells.

Spermiogenesis

Maturation process of spermatids where they elongate and shed excess cytoplasm to become sperm cells.

Acrosome

Cap-like structure formed over the nucleus of a sperm cell that assists during fertilization.

Hormonal Control (HPG Axis)

Regulation of testosterone production through a negative feedback loop involving the hypothalamus, pituitary gland, and testes.

Infertility

Inability to produce pregnancy after 1 year, often due to low sperm count or hormonal imbalances.

Cryptorchidism

Condition where the testes fail to descend into the scrotum, resulting in no sperm production.

Erection

Stiffening of the penis allowing it to enter the vagina, results from engorgement with blood due to parasympathetic reflex.

Ejaculation

Expelling semen from the penis, under sympathetic control with two stages: emission and expulsion.

Emission

Movement of sperm and semen into the male urethra.

Expulsion

Movement of semen from the urethra, resulting from skeletal muscle contraction of the penis.

Male Secondary Sex Characteristics

Characteristics that develop at puberty due to increased testosterone levels, including growth of hair, deepened voice, and thickened skin.

Male Secondary Somatic Characteristics

Characteristics that develop due to increased testosterone levels, including denser bone, increased muscle mass, and increased number of erythrocytes.