Reproductive Flashcards
Reproductive Objectives
What are gonads?
Reproductive organs that produce gametes and hormones
What is the pathway of spermatozoa?
Seminiferous tubules to epididymis to vas deferens to ejaculatory duct to urethra
What is the epididymis?
Monitors fluid secretions by seminiferous tubules.
Recycles damaged spermatozoa.
Stores and protects spermatozoa.
Site of spermatozoa maturation.
What is the vas deferens?
Helps propel sperm into ejaculatory duct via peristaltic contractions
What is histology of fallopian tubes?
Ciliated columnar epithelium and smooth muscle that transports oocyte along the tube
What is a testicular lobule?
Contains seminiferous tubules, site of spermatogenesis.
What are interstitial cells of Leydig?
Secrete testosterone in response to LH
What are the coverings of testes?
- Tunica vaginalis: superficial, derived from peritoneum.
2. Tunica albuginea.
What is the dartos muscle?
Smooth muscle in dermis of scrotum, elevates testes and causes wrinkled scrotum
What is cremaster muscle?
Skeletal muscle, tenses scrotum and pulls testes closer to body (temperature regulation)
What is mitosis?
Part of somatic cell division, produces 2 diploid daughter cells
What is a zygote?
Fertilized egg
What is process of spermiogenesis?
1. Spermatogonium Mitosis 2. Primary spermatocyte Meiosis I 3. Secondary spermatocyte Meiosis II 4. Spermatid Spermiogenesis 5. Spermatozoa
Anatomy of a spermatozoon?
- Head (nucleus and acrosome)
- Neck (contains centrioles)
- Middle piece (mitochondria in spiral around microtubules)
- Tail/flagellum (Moves in whiplike, corkscrew motion)
What are the contents of semen?
- Spermatozoa (20-100 million per mL)
- Seminal fluid (Lots of fructose, alkaline, Seminal gland 60%, prostate gland 30%, bulbourethral gland 5%)
- Enzymes (dissolve mucus, muscle contraction, antibiotic, clot/un-clot semen)
What is role of FSH in men?
Stimulates nurse cells (Sertoli) in spermatogenesis
What is role of LH in men?
Stimulates interstitial cells (Leydig) to secrete testosterone
What is role of GnRH in men?
Stimulates FSH and LH secretion
What is role of Testosterone in men?
Establish and maintain male secondary sex characteristics, and sexual behavior. Promote maturation of spermatozoa. Inhibit GnRH
What is the follicular phase of the ovarian cycle?
- Begins on first day of menstruation. Begins when FSH stimulates secondary follicle to tertiary follicle.
- As follicle grows and secretes more estrogen, the estrogen (and inhibin) inhibits FSH and LH. However, estrogen increases to the point that it STIMULATES LH secretion.
- Around day 14, massive surge in LH stimulates ovulation, which is the end of follicular phase
What is the luteal phase of ovarian cycle?
Postovulatory phase.
- Empty tertiary follicle collapses, LH turns it into corpus luteum.
- Corpus luteum secretes progesterone (and some estrogen), which prepares uterus for pregnancy
- Corpus luteum degenerates 12 days after ovulation (unless fertilization occurs). Decrease in estrogen and progesterone levels stimulates GnRH to stimulate more FSH, will starts a new cycle
Why is the suspensory ligament significant to the ovary?
It brings the ovarian artery, ovary vein, and ovarian nerve plexus to the ovary.
What are two layers of endometrium?
- Functional layer: uterine glands that change thickness/structure during uterine cycle
- Basal layer: attaches endometrium to myometrium (stays constant)
What is structure of uterine (fallopian) tube?
- Infundibulum: closest to ovary, contains fimbriae
- Ampulla: where fertilization typically happens
- Isthmus: opens to uterine cavity
What are 3 stages of uterine cycle?
- Menses: Degeneration and shedding of endometrial layer, constriction of spiral arteries
- Proliferative phase: Estrogens secreted by developing ovarian follicles stimulate functional layer growth of endometrium.
- Secretory phase: Progesterone and estrogen stimulate functional layer growth to prepare for pregnancy. Persists until corpus luteum atresia
What is blood supply to uterus?
- Uterine artery and vein
- Ovarian artery and vein
- Myometrium supply: arcuate, radial, basal arteries
- Endometrial supply: Spiral arteries
What are the 4 “arches”?
- Adrenarche: Prior to puberty
- Thelarche: breast development
- Pubarche: axillary and pubic hair development
- Menarche: first menstrual period
Terminal duct lobular unit?
Lobules made up of many acini (produce milk), drain into smaller ducts, bigger ducts (intralobular duct), bigger ducts (extralobular duct), nipple.
Mammogenesis
Breast growth and development (estrogen for growth of acini)
Progesterone for maturing acini.
Lactogenesis
Initiation of milk secretion (sharp drop in progesterone with delivery of fetus increases prolactin and low estrogen environment)
Galactokinesis
Ejection of milk (oxytocin, myoepithelial cells contract, propel milk into terminal ducts)
Galactopoiesis
Maintenance of established milk production (requires suckling which increases prolactin)
Involution
Termination of milk production