Mod 10 - Reproductive system

  1. What are the three major components of the indifferent embryonic stage and what is the fate of each of them in male/female
    • 1) mesonephric ducts: male- epidid., vas def., sem. vesic.; female - regress
    • 2) mesonephric tubules: male - efferent ductules (connect epidid to testes); females - regress
    • 3) paramesonephric ducts: male- regress; female - uterine tubes, uterus, cervix, prox 1/3 of vagina
  2. What are the embryological origins of the vagina?
    • prox 1/3: paramesonephric duct
    • distal 2/3: outgrowth of urogenital sinus
  3. What are the 3 major components of the developing external genitalia and the fate of each of them in male/female
    • 1) urogenital fold: male - penile urethra; female - labia minor
    • 2) genital tubercle: male - penis and glans; female - clitorus
    • 3) labioscrotal swelling: male - scrotum; female - labia majora
  4. Describe male and female pseudohermaphrodism
    male: genetically male, phenotypically female. either androgen or androgen receptor deficiency. 

    female: missing an enzyme that makes cortisol and aldosterone. Progesterone is a precursor to cortisol, aldosterone, and androgens. Since the cortisol and aldosterone pathway is knocked out, the reaction shifts to make more androgens, causing the masculization of genitals
  5. describe genetic sex determination
    • 1) meiosis gives haploid gametes
    • 2) genetic sex determined at fert (sperm)
    • 3a) XX: indifferent gonad becomes ovary
    • 3b) XY: testes-determining genes (SRY) on short arm of Y chrom
    • 4) phenotype modulated by endo and paracrine  hormones
  6. Describe Turner's Syndrome
    • -monosomy of X usually
    • -female sexual characteristics are present, but underdeveloped
    •   -small breasts, small ovaries, amenorrhea
    • -webbed neck, short
  7. Describe Klinefelter Syndrome.
    • - XXY karyotype
    • - small testicles and reduced fertility
    • - failure of an X chromosome to separate in meiosis
    • - tall
  8. Describe XYY syndrome
    • - almost always asymptomatic
    • - normal testosterone levels
  9. Describe senescence
    • - decreased testosterone around 60
    • - decreased bone formation, libido, facial hair, muscle mass
  10. List seven causes of male infertility
    • 1) low sperm count (oligospermia): most common, many causes
    • 2) Absence of sperm: "sertoli only syndrome", lots of sertolo cells, but no germ cells
    • 3) obstructions: vas deferens occluded, many causes
    • 4) congenital abnormalities: imcomplete development of some key portion
    • 5) environmental factors: e.g. smoking
    • 6) sperm factors
    • 7) leading cause: e.g. vasectomy
  11. How does viagra work?
    normally: cGMP causes the SM to relax allowing for erection

    pathology: excessive breakdown of cGMP to GMP via PDE-5

    Viagra inhibits PDE-5, thus increasing cGMP levels and giving you a mad boner
  12. Describe the interplay of hormones during the ovarian cycle
    • 1) small FSH surge recruits a cohort of follicles
    • 2) FSH slowly decreases because of a slow rise in estrogen, LH levels slowly start to increase
    • 3) finally the follicle releases a surge of estrogen causes a surge of LH from the pituitary
    • 4) LH surge causes the dominant follicle to ovulate
    • 5) corpus luteum produces estrogen, progesterone, and inhibin, which all suppress FSH and LH
    • 6) eventually the c. luteum atrophies and FSH increases and back to 1

    1-4 is follicular phase, 5 and 6 in luteal phase
  13. Describe the endometrial cycle
    • 1) slow rise of estrogen levels thanks to granulosa cells, causes endometrial cells to proliferate (proliferative phase)
    • 2) further growth and development by progesterones and estrogens produced by c. luteum (secretory phase)
    • 3) withdrawal of progesterone and estrogen cause start of the menstrual phase. Then back to 1
  14. What are some causes of amenorrhea?
    Primary: gonadal problems, mullerian duct problems, FSH and LH receptor problems, others

    Secondary: pregnancy, menopause, exercise, eating disorders, others
  15. How does the progestin-estrogen contraceptive pill work?
    supplemental progesterone and estrogen inhibit FSH and LH levels (via hypothalamus and pituitary). low FSH prevents follicular maturation, low LH prevents ovulation. Stop taking from day 22-28 to allow endometrial bleeding.
  16. Describe where the tunica albuginia and seminiferous tubules are
    Image Upload 1
  17. What is the pampiniform venous plexus?
    countercurrent heat exchanger, artery surrounded by cooler venous plexus
  18. What are the functions of Sertoli cells
    • 1) support of germ cells
    • 2) blood-testis barrier
    • 3) phagocytosis of germ cell cytoplasm
    • 4) secretion of testicular fluid and androgen binding protein
    • 5) regulate spermatogenesis
  19. Describe the sequence of secretions of accessory glands
    • 1) bulbourethral (after erection)
    • 2) Prostate secretions and spermatozoa from vas deferens just before ejaculation
    • 3) secretions from seminal vesicles
  20. What are the following (starred) structures?
    Image Upload 2
    Image Upload 3

    • Left picture left to right
    • -iliac crest
    • -ilium
    • -ala of sacrum
    • -sacrum
    • -pubic symphysis
    • -sacro-iliac joint
    • -ASIS

    • Right picture (left to right)
    • -lesser sciatic foramen
    • -ischial spine
    • -greater sciatic foramen
    • -Pelvic outlet (red line)
    • -PSIS
    • -ischial tuberosity
  21. identify all of the red marks
    Image Upload 4
    • Image Upload 5
    • Red circle is acetabulum (on all three bones)
    • From left to right:
    • -ASIS
    • -pubis
    • -iliac fossa
    • -arcuate line
    • -obturator foramen
    • -greater sciatic notch
    • -ischial spine
    • -lesser sciatic notch
    • -ischial tuberosity
    • -PSIS
  22. List the important landmarks (sup and post) surrounding the bladder in males and females. describe neck and trigone.
    • Superior: parietal peritoneum (male); uterus (female)
    • posterior: seminal vesicle and rectum (male); vagina and cervix (female)
    • neck: leads to urethra
    • trigone: smooth triangle on post surface between ureters and urethra
  23. Describe the relationships of the ureters in males and females
    • passes under uterine artery (water under the bridge)
    • passes under the vas deferens (semen on the water)
  24. Describe the route of the vas deferens
    epididymus-> spermatic cord-> inguinal canal -> over pelvic brim -> over the ureter -> joins seminal vesicles posterior to bladder
  25. Describe the lobes/zones of the prostate.
    Image Upload 6
    Image Upload 7
  26. What structures are embedded in the broad ligament?
    • -ovary
    • -uterine tube
    • -round lig
    • -susp lig
    • -ovarian lig
  27. Describe the boundaries of perineum and name its two sub triangles
    • Boundaries:
    • pubic symphysis, ischeal tuberosities (medial thighs), tip of coccyx (superior border of gluteal cleft
    • Subtriangles: urogenital, anal
  28. Describe the maternal-placental-fetal unit
    • 1) corpus luteum make E&P at first
    • 2) c. luteum is initially "rescued" by hCG and it alone initially supplies the hormones
    • 3) eventually the need for steroid hormones increases and the placenta starts making steroid hormones
    • 4) finally the need is so great that both the mother and fetus start making steroid hormones (after 8 weeks)

    intermediate molecules of synthesis are exchanged between the three
  29. List 6 factors determining fetal-placental exchange.
    • 1) concentration of substance in maternal blood
    • 2) mechanism of transfer across placental cell membranes
    • 3) concentration of subs in lacunae
    • 4) availability of carrier proteins if required
    • 5) placental consumption of subs
    • 6) concentration in blood feeding fetal side
  30. Describe folliculogenesis
    • 1) a cohort of follicles recruited each cycle
    • 2) takes about 290 days (ten cycles) before a primordial follicle fully matures
    • 3) usually only dominant follicle reaches full maturity, the rest undergo atresia
  31. What do granulosa and thecal cells do in the corpus luteum?
    • granulosa: produce estrogens and pregesterone from androgens
    • thecal cells: produce androgens, have receptors for hCG
  32. describe the histology of the oviduct (uterine tube)
    • 1) mucosa with longitudinal folds, simple columnar with ciliated and non-ciliated) secretory cells.
    • 2) muscularis: circular and longitudinal
    • 3) serosa: BVs and nerves
  33. How does the oviduct capture an oocyte?
    large veins become engorged which brings finbrae in contact with ovary. After that the cilia do the work
  34. describe the endometrium changes during menstruation
    • 1) 2 d before menses, contraction/relaxation of spiral aa
    • 2) menstruation (day 1) ischemia and loss of functional layer
    • 3) after this endometrium is 1 mm thick
    • 4) gradually gets thicker during prolif. phase
  35. List the layers in the placental barrier (early and at term, maternal to fetal)
    • early:
    •   -syncytiotrophoblast
    •   -continuous cytotrophoblast
    •   -BM of cytotrophoblast
    •   -CT of villus
    •   -BM of endothelium
    •   -endothelium of fetal capp.

    • term:
    •   -same as above except cytotrophblast is discontinuous and sync forms knobs
  36. What are the stages of labour?
    • 1) tranquility: uterine muscle is chill
    • 2) uterine awakening: extending to complete cervical dilation
    • 3) active labour: cervical dilation to delivery
    • 4) from fetal delivery to placental expulsion
  37. Describe the CV and resp changes that happen at birth
    • -vasoconstriction of umbilical artery
    • -first breath (surfactant is important)
    • -loss of placental circ. increases SVR and breathing decreases PVR
    • -therefore R atrial pressure decreases relative to L atrial pressure and foramen ovale closes
    • -ductus arteriosus b/n pulm a and aorta close in response to increased PO2
    • -pulmonary and systemic circ now in series
    • -ductus venosus, which mixed portal blood with umbilical vein closes, diverting all the portal blood to the liver
  38. Why have fetal shunts?
    • -allows most blood to bypass non-functional lungs (Da and FO)
    • -pulm circuit is in parallel with systemic circuit
    • -
  39. Describe the effect of suckling stimulus on hormone release
    • 1) physical stimulation by suckling goes to hypothalamus
    • 2) increases oxytocin and prolactin
    • 3) inhibits GnRH (thereby reducing LH and FSH), therefore reducing the ovarian cycle. Harder to get pregnant.
Card Set
Mod 10 - Reproductive system
Mod 10