Reproductive Embryology Flashcards
Which ridge of the intermediate mesoderm makes the genital system?
Gonadal or genital ridge
When is phenotypic sex made manifest?
Seventh week of development
What gene is important for male phenotype? What does it produce?
SRY (sex determining region of Y)
Testis-determining factor
What is the most common abnormality of sexual differentiation?
Klinefelter syndrome
What is the genotype of klinefelter syndrome?
XXY genotype
Are people affected by Klinefelter male or female?
Male, with femininization
What are the symptoms of turner syndrome?
Short stature High arched palate Webbed neck Shield-like chest Inverted nipples Cardiac and renal anomalies
What is the genotype of Turner syndrome?
XO 45
What genotype do true hermaphrodites have?
XX
Where do gametes come from in development?
Umbilical vesicle (yolk sac)
Where to gametes migrate to in development?
Genital ridge
When does gamete migration happen? (what week)
5th week
What do developing gonads consist of?
Mesothelium
Mesenchyme
Primordial germ cells
What serve as the precursors to the Sertoli cells?
Cortical cords
What do the cortical cords form?
Sertoli cells
Seminiferous tubules
Rete testis
Tubuli recti
What do the mesonephric ductules become?
Efferent ductules, then distal epididymis
What forms the interstitial cells of Leydig?
Mesenchyme
_______ induces Sertoli cells to produce ________, which suppresses development of the ___________ ducts.
hCG induces
Anti-mullerian hormone (Mullerian inhibitor substance)
Paramesonephric (mullerian ducts)
What does the indifferent sexual duct system consist of?
Mesonephric ducts (Wolffian) Paramesonephric ducts (Mullerian)
Where do the caudal ends of the paramesonephric ducts fuse?
Urogenital sinus
What is the remnant of the paramesonephric duct called in males?
Prostatic utricle
What stimulates the mesonephric duct to mature? What does it turn into?
Testosterone from interstitial cells
Epididymis, ductus deferens, ejaculatory duct
What stimulates the development of the seminal vesicles? Where does it bud out from?
Testosterone
Ductus deferens
What forms the prostate gland?
Epithelial outgrowth of pelvic urogenital sinus
What forms the bulbourethral gland?
Epithelial outgrowth of spongy urethra (UG sinus)
The absence of this allows paramesonephric duct development?
Anti-mullerian hormone
When the two paramesonephric ducts fuse, what forms?
Uterovaginal primordium
What forms the upper one-third of the vagina?
Uterovaginal primordium
What forms the lower two-thirds of the vagina?
Urogenital sinus
What are the female homologues of the bulbourethral glands?
Greater vestibular glands
What causes mesonephric ducts to regress?
Lack of testosterone
If the mesonephric ducts fail to regress completely in the female, what can result?
Gardner’s duct (perhaps cystic)
