GU Embryology Flashcards
kidenys, ureters, bladder form from which layer?
intermediate mesoderm
3 stages of the kidney
Which is the adult kidney derived from?
1) pronephros
2) mesonephros
3) metanephros
Adult kidney is derived from metanephros
excretory unit forms form _____
mesonephric tubules
Mesonephric tubules form Bowman’s capsule, glomerulus, renal corpuscle.
mesonephroi (function, time functional, regression)
Produce small amounts of urine.
6th-12th weeks.
Regress in FEMALEs, persist in males as genital duct system
ureteric bud
Branched from caudal end of mesonephric duct.
Forms collecting system of kidney (collecting ducts, calyces, ureter)
two structures that form the kidney
ureteric bud
metanephric blastema
metanephric blastema
Forms the rest of the kidney that the ureteric bud does not form.
Ureteric bud penetrates metanephric blastema and bifurcates
cloacal region is divided by _________________ into a ventral _________ and a dorsal ___________
cloacal region is divided by urogenital septum into a ventral urogenital sinus and a dorsal anorectal canal
ascent of kidneys
Form in sacral area.
Ascend to lumbar region by differential growth of the body.
Revascularized. If original vessels do not regress, then accessory renal arteries are present.
horseshoe kidney
Inferior poles of two mesonephroi fuse during ascent of kidneys.
Cannot migrate further up than the origin of the IMA
pelvic kidney
Failure of migration of one/both kidneys.
Kidney is retained in the pelvis.
No adverse effect on kidney function
renal agenesis
Kidney fails to develop.
Due to faulty tissue-tissue interactions between ureteric bud and nephrogenic mesenchyme
bilateral can be fatal (potter syndrome)
potter syndrome
Bilateral renal agenesis.
Oligohydramnios compresses fetus.
Stillborn or die soon after birth.
(amniotic fluid is largely made from fetal urination )
duplication of ureter
Variable in length.
Occurs if initial branching of ureteric bud is not incorporated into developing kidneys.
urachal cyst
Small patent area of the urachus.
Only detected if it becomes infected.
urachal sinus
Lumen in superior portion of urachus remains patent.
Opens at urachus.
Fluid is from endothelial lining, not urine
urachal fistula
Rare.
Entire urachus remains patent.
Allows urine to exit from urachal orifice.
SRY (what it encodes, what that does)
SRY = Sex-determining region of the Y chromosome. Encodes TDF (testes-determining factor).
SRY directs differentiation of Sertoli cells (directs male development).
In ABSENCE of SRY/TDF, female development occurs.
absence of testosterone on mesonephric ducts, paramesonephric ducts
Mesonephric ducts degenerate.
Paramesonephric ducts give rise to female reproductive system.
presence of testosterone on mesonephric ducts, paramesonephric ducts
Mesonephric ducts remain.
Paramesonephric ducts degenerate.
paramesonephric ducts develop into (male and female)
FEMALE:
Uterine tubes, uterus, cervix, superior 2/3 of vagina, Hydatid of Morgagni
MALE:
appendix testes
mesonephric ducts develop into (male/female)
FEMALE:
appendix vesiculosa, Gartner’s duct
MALE:
epididymus, ductus deferens, seminal vesicles, ejaculatory duct
mesonephric tubules develop into (adult male/female)
FEMALE:
epoophoron, paraoophoron
MALE:
efferent ductules, paradidymus
phallus develops into (adult male/female)
FEMALE:
clitoris
MALE:
glans and body of penis
urogenital folds develop into (adult male/female)
FEMALE: labia minora
MALE: penile raphe
labioscrotal folds develop into (adult male/female)
FEMALE: labia majora, mons pubis
MALE: scrotum, scrotal raphe
gubernaculum develops into (adult male/female)
FEMALE: ovarian ligament
MALE: gubernaculum testes
didelphic uterus
Paramesonephric ducts fuse to urogenital sinus separately.
2 vaginas, connected to own uterus separately
unicornate uterus
One entire Mullerian duct regresses or fails to elongate.
hypospadias
Urethra opens onto VENTRAL (underside) surface of penis.
Failure of urogenital folds to fuse normally
epispadias
Urethra opens on DORSAL side of penis.
Failure of urogenital folds to fuse normally
testicular hydrocele
Lumen between tunica vaginalis and peritoneal cavity fills with serous secretions.
cryptorchidism
Undescended testes.
male pseudohermaphroditism
Genetic males with feminized genitals.
Androgen insensitivity syndrome (androgens do not work on target cells).
5-alpha reductase deficiency (cannot make dihydrotestosterone).
female psuedohermaphroditism
Genetic females with masulinized genitals.
Disorder of adrenal glands that cause excessive production of androgens.
klinefelter syndrome
Extra X chromosome in males (XXY).
Failure of Leydig cells to produce sufficient amounts of male steroids.
Small testes, azoospermia/oliogospermia.
Gynecomastia, eunuchoidism
turner syndrome
45X or 46XX/45X mosaicism.
Failure of normal sexual maturation at puberty, short stature, webbed neck, coarctation of aorta, cervical lymphatic cysts
