Untitled Quiz

Male Reproductive System

• Testes are located inside the scrotum, a protective sac of skin and muscle beneath the penis.
• Testes function to produce sperm through spermatogenesis and secrete androgens (male sex hormones).
• Spermatogenesis requires slightly lower temperatures than body temperature, hence the location outside the body in the scrotum.
• Testosterone is the primary androgen and triggers pubertal changes like facial/body hair, deepening voice, bone/muscle development, and sperm production.

Male Reproductive Ducts

• These ducts store and transport sperm out of the body.
• Paired structures include the epididymis, vas deferens, and ejaculatory duct.
• The urethra is a single structure.
• Epididymis is a coiled tube on the testicle where sperm mature and are stored for up to 2 months before being reabsorbed.
• Vas deferens connects the epididymis to the seminal vesicle, transporting mature sperm upwards from the scrotum to the pelvic cavity, over the bladder, and behind the prostate.
• During ejaculation, smooth muscle in the vas deferens contracts to rapidly move sperm.
• Each vas deferens joins a seminal vesicle and forms a short tube called the ejaculatory duct.
• Seminal vesicle fluid mixes with sperm in the ejaculatory duct to form semen, which empties into the urethra.
• The urethra is a shared duct for both semen and urine but not simultaneously.

Female Reproductive System

• Ovaries, located in the pelvic cavity, produce ova (eggs) and secrete hormones.
• Estrogen and progesterone are the primary female sex hormones and influence the development of female reproductive organs, menstruation, pregnancy, and secondary sexual characteristics (breast enlargement, hip widening, pubic hair).

Female Reproductive Ducts

• Fallopian tubes (uterine tubes) are connected to the ovaries and uterus.
• They transport mature ova from the ovary to the uterus.
• After ovulation, fimbriae (finger-like projections) sweep the ovum into the fallopian tube.
• Peristalsis (wave-like contractions) and cilia (tiny hair-like projections) guide the ovum towards the uterus.
• Fertilization typically occurs in the fallopian tubes.
• The fertilized egg (zygote) then travels to the uterus.

Uterus

• The uterus (womb) is a hollow, pear-shaped muscular organ located behind the bladder and in front of the rectum.
• It’s divided into the fundus (top), corpus (body), and cervix (lower section).
• The uterus protects and nourishes the embryo/fetus during pregnancy.
• The uterus wall has three layers: endometrium (innermost), myometrium (middle), and perimetrium (outermost).
• The endometrium is a blood tissue lining where a fertilized egg implants, providing nourishment during early development.
• If the egg isn’t fertilized, the endometrium sheds, leading to menstruation.
• The myometrium is the muscle layer that stretches and expands during pregnancy and contracts to help deliver the fetus during childbirth.
• The perimetrium is a protective membrane.

Vagina

• The vagina is a muscular tube connecting the cervix to the external body.
• It’s the female organ for sexual intercourse and the pathway for menstrual flow.
• Vaginal muscle tissue expands during intercourse and childbirth.

Vulva

• External structures of the female reproductive system collectively known as the vulva.
• Components include the mons pubis, labia majora, labia minora, clitoris, and vestibule.
• The vestibule contains the urethral and vaginal openings and the paraurethral (Skene’s) and Bartholin’s glands.
• The mons pubis is a fatty tissue pad covering the pubic bone.
• The labia majora are elongated folds of fatty skin protecting the vaginal opening.
• The labia minora are inner folds of skin enclosed by the labia majora.
• The clitoris is anterior to the vestibule, causing arousal and vaginal preparation for intercourse when stimulated.
• The paraurethral glands secrete lubricating mucus with antimicrobial properties for the urethra.
• The Bartholin’s glands secrete lubricating mucus for the vagina during intercourse.

Menstrual Cycle

• It begins after puberty, occurring every 28 days on average (can vary) to prepare the body for potential pregnancy.
• The cycle has three phases: follicular, ovulation, and luteal.
• The follicular phase starts with menstruation (lasting 5-7 days) triggered by the deterioration of the corpus luteum from the last cycle and hormonal decrease.
• The hypothalamus signals the pituitary gland to release FSH (follicle stimulating hormone), initiating the development of several ovarian follicles containing oocytes (immature ova).
• One follicle becomes dominant, while the others are reabsorbed.
• Estrogen levels rise during follicular phase, thickening the endometrium.
• The ovulation phase begins around day 14 when rising estrogen triggers a surge in LH (luteinizing hormone).
• LH causes the dominant follicle to rupture and release an ovum (egg).
• The egg travels to the uterus and can be fertilized by sperm, with pregnancy most likely to occur in this phase.
• Estrogen levels decrease, and progesterone levels increase during this phase.
• The luteal phase lasts from day 16-28 and involves the ruptured follicle becoming a mass of cells (corpus luteum), which secretes progesterone to maintain the uterine lining for potential pregnancy.
• If pregnancy occurs, the developing placenta releases hCG (human chorionic gonadotropin) to keep the corpus luteum functioning, nourishing the fertilized egg.
• If pregnancy does not occur, the corpus luteum deteriorates, causing progesterone and estrogen levels to drop, marking the start of a new cycle.

Mammary Glands

• Accessory organs in the female reproductive system located in the breasts.
• They produce milk through a system of ducts, secreted through the nipple after childbirth to nourish the newborn.