Renal Embryology Week 1, part 2

kschmidt's version from 2015-12-18 07:54


Question Answer
the primitive urogenital sinus has ? partscranial (vesical) part, middle (pelvic), and caudal (phallic)
the cranial/vesicle part of the primitive urogenital sinus is continuous withallantois and receives the Wolffian ducts
the dilated part of the primitive urogential sinus is thecranial part
the cranial part of the urogenital sinus forms theurinary bladder
the middle/pelvic part of UG sinus forms intramural and prostatic parts of male urethra and ENTIRE female urethra
caudal/phallic part of UG sinus forms spongy urethra in males, gonadals, and external genital organs
caudal part of mesonephric ducts get absorbed into the bladder to form musculature and connective tissue of the trigone & part of the genital ductal system in males
the smooth part of bladder is called what and located wheretrigone; between opening of left and right ureters and thickening of urethra (or internal urethra orifice)
the degenerated allantois becomes theurachus aka median umbilical ligament
the epithelial lining of the bladder is derived from theendoderm (vesical part of UG sinus)
mesopnephric ducts form muscle and connective tissue of the trigone
muscles in the rest of the bladder wall are fromsplanchnic mesoderm
# of parts to male urethra4 (intramural, prosthetic, spongy, intermediate)
the intramural and prostatic parts of male urethra are derived from pelvic part of UG sinus
spongy aka penile urethra is from phallic part of UG sinus (endoderm) EXCEPT for the glans part
the glandular part of penile/spongy urethra is fromthe surface ECTOderm
intermediate part of male urethra is fromphalic part of UG sinus?
muscles and connective tissue of urethra are derived fromsplanchnic mesoderm
agenesis of kidneys meansthe kidneys do not form at all (e.g. of bud)
bilateral agenesis vs unilateralbilateral - incompatible with life vs unilateral - more common, L. kidney usually absent, and asymptomatic if other kidney is normal
agenesis is due to early degeneration or failure of formation of the ureteric bud
a bifid ureter is usually due toearly splitting of ureteric bud
bifid ureter results in partial or complete duplication of the ureter
if 2 ureteric buds develop due to a bifid ureter, one ureter may be positioned normally (w/bladder) while other may open into vagina, bladder, or vestibule
current theory behind renal cystsabnormal collecting system development; wide dilations of ductal system esp. loops of henle
renal cysts are problematic becausecan occupy majority of kidney volume --> prevent normal parenchyme function --> renal insufficiency
multiples (100s) of small cysts in parenchyma of kidneys is calledpolycystic kidney disease
horseshoe kidney is common and the result offusion of lower poles while passing through umbilical form (arterial fork of umbilical arteries) in ascent
root of the ? prevents further ascent of horseshoe kidneyinferior mesenteric artery
what happens with ureters in horseshoe kidney?urters arise anteriorly, passing over the joined lower poles (normal ureters-->so often asymptomatic)
more likely to get ? with horseshoe kidneyswillis? tumors( 8x more likely)
fetal kidney is lobulated with fissues on its surface, which disappear with growth of connective tissue, vascularity, and size of nephrons at time of birth. failure to do so results inkidney showing fetal lobulations - functionally fine
indifferent gonad: identical betwen male and female before what weekweek 7
mesonephric ducts akaWolfian duct (male reproductive tract)
paramesonephric duct akaMullerian (female reproductive tract)
wolfian duct is lateral to paramesonephritic duct
when gonads are developing in posterior abdominal wall, if mesonephritic duct disappears, end up with ovaries
if male embryo, what duct disappears in forming gonads?paramesonephric duct disappears
SRY gene on Y chromosome secretestestes developing factor (TDF) - if have TDF, get testes and if not, get ovaries
with testes, producetestosterone (interstital or Leydig cells) and MIS (sertoli cells)
ovaries XX - abscence of both testosterone and MIS
if mesonephric duct persist in the female genital system, can developgartner (duct) cysts