Embryology of the Kidney Flashcards
what 4 parts are the urinary system made up of
kidneys
ureters
urinary bladder
urethra
what two parts are the reproductive system made up of
internal/external genitalia
when does the formation of the pronephros occur
4th week
describe the formation of the pronephros
intermediate mesoderm in the cervical region condenses and reorganises
forms epithelial buds - disappear around day 25
how does the mesonephric duct form
intermediate mesoderm in the lower cervical region induced to epithelise forming a solid duct
what does the mesonephric duct fuse with and on what day
cloaca on day 26 (develops caudally)
what is the formation of the mesonephros derived from
intermediate mesoderm in upper thoracic to upper lumbar regions
what does the development of the mesonephric duct induce
formation of the mesonephric buds from mesenchyme
formation of the mesonephric tubules occur in what fashion
carniocaudally
what do mesonephric tubules differentiate into
S shape and bowman capsule
what is the renal corpuscle made from
bowman capsule and glomerulus
what is the glomerulus made out of
tuft of capillaries which form at the medial end of the tubule
how many of the cranial-most tubules fun with the mesonephric duct
6/7
when do the tubules first start producing small amounts of urine
between weeks 6-10
what happens to the mesonephric ducts after week ten
males - develop into reproductive structures
females - regress
where does gonadal development take place
on the medial aspect of the mesonephric ridge
what parts make up the collection portion
collecting ducts
major and minor calyces
renal pelvis
ureter
what parts make up the excretory portion
bowmans capsule
PCT
LoH
DCT
what happens to the ureteric buds by day 32
penetrate the metanephric mesenchyme
what is the biurification pathway after the ureteric bud penetrates the metanephric mesenchyme
renal ampulla renal pelvis major calyces minor calyces collecting ducts
what covers newly formed collecting tubules
metanephric tissue cap
what does the metanephric tissue cap cause
specific branching of the tubule
differentiation of cells in the metanephric cap to form renal vesicle
what does the renal vesicle turn into
s shape tubule and bowman capsule
what 3 parts make up the nephron
renal corpuscle, tubule and collecting tubule
describe duplication of the ureter
premature biurification of the ureteric bud
can be partial or complete
present in approx 5%
describe unilateral and bilateral renal genesis
early degeneration of ureteric bud or failed interaction between ureteric and meseneohric tissue cap
unilateral - generally asymptomatic, hypertrophy of remaining kidney
bilateral - incompatible with life
what is oligohydraminos
bilateral renal agenesis
decreased volume amniotic fluid causing the foetus to present with potter sequence
describe polycystic kidney disease
autosomal dominant occurs 1 in 1000
cysts form on all parts of the nephron
autosomal recessive 1 in 5000
cysts form in collecting ducts and kidneys enlarge to renal failure in childhood
caused by gene mutations in cilia
what is ascent of kidneys caused by
growth and elongation of developing foetus
by what week do kidneys fully relocate
week 9
what is horseshoe kidney
occurs in around 1/600 people
inferior poles of kidney fuse
resides lower in the lumbar region
usually asymptomatic
what happens to the cloaca in week 4-7
divides into the urogenital sinus and the anal canal which are separated by urorectal septum
what is the urogenetial sinus divided into
upper part - presumptive urinary bladder
pelvic part - urethra
phallic part - penile urethra (males), vestibule (females)
what is the bladder initially continuous with
allantois
what happens to the allantois
obliterates to form the urachus that connects the apex of the bladder with the umbilicus in the adult
