Lecture 7 (Urogenital) Flashcards
When does the pronephros begin to appear? What else are differentiating with it?
during week 3
mesonephos and mesonephric duct
When do the metanephric mesenchyme and ureteric bud appear?
end of week3/beginning of wk4
when do the major calyces form?
week 5
When do minor calyces form? what are these?
week 7
chambers that urine passes through
when do functional nephrons begin to form in the renal vesicles?
weeks 10-12
When is the renal collecting duct system complete?
roughly week 32
When does the bladder develop?
week 5
When do the kidneys ascend?
weeks 6-7
What are the major molecular determinants in the urogenital system?
BMP4, BMP7, FGF8, GDNF, VEGF, WNT4, 5a, and 9b
What are the three regions of the kidney system during development? What direction do they extend?
pronephros
mesonephros
metanephros
cervical to pelvic region along posterior wall
Describe the pronephros:
forms in the cervical region, rudimentary
provides intermediate mesoderm cells direction until they become mesonephros
Describe the mesonephros:
forms in thoracic and upper lumbar regions (may fxn briefly)
consists of filtration unit na ducts
degenerates almost completely in females, contributes to duct work of male reproductive system
Describe the metanephros:
definitive kidney system
forms in pelvic region
begins fxn in 10-12th wks
When do the kidney regions appear and degenerate?
pro-: degenerates in 4th wk
meso-: forming 4-6, starts to degenerate as meta- appears in 5th wk
What makes up a nephron?
Bowman’s capsule + glomerulus + excretory tubules
The ureteric bud forms the: __________.
What does it form from?
collecting system for the definitive kidney
outgrowth from the mesonephric duct into the metanephros
What forms as the ureteric buds branches into the metanephros?
induces mesoderm to form filtration units (nephrons)
When do the kidneys ascend? Birth defects associated?
week 12
pelvice or horseshoe kidneys
The anterior portion of the cloaca becomes the:
urogenital sinus
What does the urogenital sinus become?
upper portion -> bladder
caudal -> urethra
During what time does the genital system develop?
weeks 3-12
Where does the gonadal/genital ridge form?
next to the mesonephric system
trace the path of PGC migration (when does this occur?):
formed in yolk sac endoderm -> move along hindgut through dorsal mesentery -> genital ridge
begin migration in 4th week and arrive at ridge in 6th week
