Male Reproductive System Quiz

Male Reproductive System

• The male reproductive system includes the testes, ducts (epididymis, ductus deferens, ejaculatory ducts, and urethra), accessory sex glands (seminal vesicles, prostate, and bulbourethral glands), and supporting structures (scrotum and penis).
• Testes produce sperm and secrete hormones.
• The duct system transports and stores sperm, aids maturation, and conveys sperm to the exterior.
• Semen contains sperm and secretions from accessory sex glands.
• The penis delivers sperm, and the scrotum supports the testes.
• The scrotum is a supporting structure for the testes.
• The scrotum consists of loose skin and an underlying subcu-taneous layer separated into lateral portions by a median ridge (raphe). A scrotal septum divides the scrotum into two separate sacs, one for each testis. Smooth muscle fibers (dartos muscle) regulate scrotal temperature.
• Testes (testicles) are paired oval glands measuring about 5 cm long and 2.5 cm in diameter located in the scrotum. They descend from the abdomen during fetal development.
• The tunica vaginalis is a serous membrane that partially covers the testes.
• Testes have internal compartments called lobules which contain tightly coiled seminiferous tubules.
• Sperm production (spermatogenesis) occurs in seminiferous tubules.
• Seminiferous tubules contain spermatogenic cells (sperm-forming cells) and Sertoli cells that support spermatogenesis.
• Spermatogenesis takes 65-75 days, starting with spermatogonia (stem cells) that undergo meiosis and form spermatids. These develop into sperm.
• Sertoli cells nourish spermatocytes and spermatids, phagocytize excess cytoplasm, and regulate the effects of testosterone and FSH on spermatogenesis.
• Leydig cells in the spaces between seminiferous tubules secrete testosterone.

Female Reproductive System

• Organs include ovaries, uterine (fallopian) tubes, uterus, vagina, vulva, and mammary glands.
• Ovaries produce secondary oocytes and hormones (progesterone, estrogens, inhibin, and relaxin).
• Uterine tubes transport the secondary oocyte to the uterus (fertilization site).
• The uterus is responsible for implantation, fetal development, and labor.
• The vagina receives the penis, and it is a birth canal.
• Mammary glands produce, secrete, and eject milk.
• Ovaries are almond-shaped, paired glands located in the pelvic cavity.
• Ovaries are held in place by ligaments (broad ligament, ovarian ligament, suspensory ligament).
• Ovaries contain follicles (containing oocytes) and the medulla(containing connective tissue, blood vessels, and nerves).
• Oogenesis begins before birth with oogonia.
• Many oogonia degenerate (atresia), remaining primary oocytes that arrest in prophase 1.
• During each cycle, one primary oocyte completes meiosis I, forming a secondary oocyte and first polar body.
• Ovulation releases the secondary oocyte, which possibly completes meiosis II upon fertilization.
• The uterine (menstrual) cycle is a series of cyclical changes in the endometrium to prepare for implantation.
• If fertilization does not occur, the stratum functionalis of endometrium sloughs off (menstruation).
• Hormonal control from hypothalamus (GnRh), anterior pituitary (FSH and LH), and ovaries regulate the cycle.
• The vagina is a fibromuscular canal that extends from the exterior to the cervix.

Reproductive System Ducts

• Epididymis is a comma-shaped organ lying along the posterior border of the testis.
• Epididymis's tightly coiled ductus epididymis receives sperm from rete testis.
• Sperm maturation occurs in the epididymis (acquire motility and fertility ability). Sperm may remain viable for months, then are reabsorbed.
• Ductus (vas) deferens ascends along the posterior border of the epididymis.
• Ductus deferens conveys sperm from the epididymis to the urethra via peristaltic contractions.
• Ejaculatory ducts are formed by the union of ducts from the seminal vesicles and ampullae of ductus deferens.
• The ejaculatory ducts empty into the prostatic urethra.
• The urethra is a shared terminal duct for both reproduction and urination.
• The urethra passes through the prostate, deep muscles of the perineum, and penis. It has three segments.
• The prostatic urethra passes through the prostate.
• The membranous urethra passes through the deep muscles of the perineum.
• The spongy (penile) urethra passes through the corpus spongiosum of the penis.

Accessory Sex Glands

• Seminal vesicles secrete an alkaline, viscous fluid including fructose for ATP production, prostaglandins, and clotting proteins.
• Prostate secretes a milky, slightly acidic fluid that contains citric acid, prostate-specific antigen (PSA), and other enzymes.
• Bulbourethral glands secrete an alkaline fluid that protects sperm by neutralizing acids from urine.