Flashcards in renal development Deck (16):
List the names of the sets of kidneys throughout development
The pronephros (about 3 to 4 weeks), the mesonephros (about 4 weeks-2 months), and the metanephros (about 5 weeks to maturity).
Where do all of the kidneys develop from
the nephrogenic cord within the urogenital ridge- Mesodermal cells within the nephrogenic cord develop into groupings of cells called nephrotomes that are located in each somite during embryo segmentation.
Describe development of mesonephric duct
The nephrotomes vesiculate and join laterally forming first the pronephric duct, then as nephrotomes further caudally add to it it becomes the mesonephric duct (week 5). This grows even more caudally and the pronephros degenerates, leaving the mesonephric/wolffian duct.
What is Wolffian body
development of urogenital ridge that protrudes into coelom
Discuss development of paramesonephric duct
An invagination of coelom wall which runs along the length of the wolffian body.
Male vs female ducts
Wolffian/mesonephric ducts develop into male reproductive system (degrade in females) while paramesonephric ducts /mullerian ducts develop into female repro system (degrades in males)
Describe development of metanephros- ureteric bud
at 5-6 weeks, A bud of epithelial cells from a portion of mesonephric duct forms (ureteric bud) and it is eveloped by the metanephric blastema (which will develop into parts of the kidney). The ureteric bud branches to form the ureter, renal pelvis and major/minor calyces.
Describe development of collecting ducts and tubules
The branches of the ureteric bud branch into tubules called Malpighian pyramids. The epithelia of these outgrowths
will become the collecting ducts of the kidney, then further branch into collecting tubules.
Describe development of glomeruli and nephron
Mesoderm at tips of collecting tubuless organize into a metanephric spheroid, then vesiculates to form a metanephric vesicle. The vesicle elongates to form a tubule, then folds into shape of "S" as it becomes the metanephric tubule. Meanwhile, renal artery and vein branch btw the Malpighian pyramids to form the intralobar vessels... all the way to the glomerular capillaries, efferent arterioles and vasa recta.
What does the urogenital sinus develop from
When does urogenital sinus separate from hindgut
What does the urogenital sinus develop into
bladder and urethra
discuss kidney ascent
As ureteric bud elongates, kidneys ascend from sacral region into retroperitoneal location.
What happens to the allantois
degenerates to form a fibrous cord called the urachus
What does the mesonephric duct form?
epididymis and ductus deferens in males