2. Urogenital Development Flashcards
the urogenital ridge (nephrogenic cord) arises from the __ of the trilaminar disc before giving rise to urinary and genital system
intermediate mesoderm
what are the 3 kidneys that originally develop from nephrogenic cord
pronephric, mesonephric, metanephric
which of the 3 kidneys contains functional glomeruli in week 4 and becomes ductus deferens in males around week 10
mesonephros
what is the exit point of urinary system into amniotic cavity
cloaca
which of the 3 kidneys splits into two parts: ureteric bud and a mass of mesoderm
metanephros
renogenesis (kidney development) is dependent on reciprocal induction by
RA
the renogenic mesoderm established by an RA gradient is the ___ which secretes growth factors inducing growth of ureteric bud from the caudal portion of mesonephric duct
metanephric blastema
the ureteric bud secretes growth factors stimulating metanephric blastema to become what two adult structures
glomeruli, kidney tubules
the ureteric bud becomes what adult structures
collecting duct, minor calyx, major calyx, renal pelvis, ureter
urine is produced by the metanephros to supplement amniotic fluid in utero, what is the condition of insufficient amniotic fluid
oligohydramnios
oligohydramnios can be indicative of what two conditions
bilateral renal agenesis, urethral obstruction
aberrant (accessory) renal arteries may enter kidney only cause problems when they enter at a pole obstructing
ureter
no kidneys develop in this condition diagnosed by oligohydramnios (results in potter’s syndrome)
renal agenesis
renal fusion can prevent rotation of hilum to midline or prevent ascension causing wrong placement aka
ectopic kidney
fused kidneys (horseshoe) usually found inferior to what major aortic artery
inferior mesenteric
cancer of kidney caused by WT1 gene mutations characterized by blood in urine
wilms tumor
the cloaca (common urogenital outflow in utero) gets divided by the __ into dorsal and ventral portions
urorectal septum
common urogenital outflow in utero occurs through what structure
cloaca
the cloaca when divided by urorectal septum dorsally becomes __ and ventrally becomes __
rectum, bladder
failure of __ to retract completely and close from the umbilicus leads to leakage of fecal matter
vitteline duct
failure of __ to retract completely and close from the umbilicus to become urachus leads to leakage of urine
alantois
two structures that preliminarily open into the bladder, one of which gets displaced to the prostate gland in males so that semen does not enter the bladder
ureteric bud, mesonephric duct
the triangular region of the mesonephric duct incorporated into the bladder wall forms the
trigone
along with being patent (fistula, failing to close) what other anomaly can occur with the urachus causing an abdominal mass
urachal cyst
the embryo remains genitally undifferentiated until what week of development
6
male versus female external genitalia can be recognized at what week of development
12
fetal sex is determined by encoding what region of chromosome 46
SRY
synthesis of what triggers male development? When it’s not expressed default is female
SRY protein (TDF)
SRY triggers the development of ___ into the wolffian duct which become epididymis, vas deferens, seminal vesicle, ejaculatory duct
leydig cells
SRY causes __ to develop signaling the mullein ducts to degenerate preventing female development
sertoli cells
the absence of SRY allows __ to develop which become fallopian tubes, uterus, and upper part of vagina
mullerian duct
the absence of SRY means leydig cells do not develop and thus testosterone does not signal ___ to become male genitalia
wolffian ducts
duct that plays the most essential role in male development
mesonephric
duct that plays the most essential role in female development
paramesonephric
gonads develop from intraembryonic coelom, intermediate mesoderm and ___ from yolk sac which invade dorsal mesentery and migrate to urogenital ridge
primordial germ cells
primary sex cords are aggregates that become gonad which has an outer cortex (becomes ___ in female) and inner medulla (becomes ___ in males)
ovary, testes
in females, the paramesonephric duct becomes
oviduct, uterus, upper vagina
in females, the mesonephric duct becomes
regresses
in females, the urogenital sinus
remains open
in females, the genital tubercle becomes
clitoris
in females, the labioscrotal swellings become
vulva
in males, the paramesonephric ducts
regress
in males, the urogenital sinus becomes
urethra, protate
in males, mesonephric ducts become
ductus deferens, epidydymis
in males, the genital tubercle becomes
penis
in males, the labioscrotal swellings become
scrotum
urogenital folds become __ in males
shaft
urogenital folds become __ in females
labia minora
2 uterus, 2 vagina (paramesonephric duct anomoly)
uterus didelphys
2 uterus, 1 vagina (paramesonephric duct anomoly)
uterus bicornis
(paramesonephric duct anomoly) closure of cervix or vagina
atresia
anomoly resulting in missing uterine tube, uterus, upper vagina (paramesonephric ducts don’t develop)
mullerian agenesis
incomplete fusion of urethral fold in males (occurring at glans, shaft, scrotal, perineal) harder to treat the closer it occurs to the body
hypospadias
46 XX individual who undergoes excess adrenal androgen production in utero and forms genitalia that may be masuclinization of external genitalia: labial fusion, phallic urethra, but normal ovaries
adrenal hyperplasia
46 XY individual with receptors unresponsive to androgens thus failure to masculinize and secondary female sex characteristics form at puberty- X linked
AIS Androgen Insensitivity Syndrome
autosomal recessive condition where testosterone cannot be converted to DHT thus child has ambiguous genitalia, normal ductus deferens
5ARD
