sex determination Flashcards
3 weeks (1)
PGC’s induced from mesoderm migrate out of the epiblast
6 weeks (2)
PGC’s migrate back into the genital ridge
bipotential gonads
female/xx/-ovaries male/xy/-testes
genital ridges
female- mullerian duct male- wolffian duct
(3) bipotential gonad differentiation
gonads determined by embryo chromsome, if xx-ovaries xy-testes
testes MRG
SRY
(4) duct development
male: testes secrete testosterone and anti mullerian hormone forming wolffian duct female: without testosteorne and AMH wolffian duct deteriorates and mullerian duct forms
wolffian tube derivatives
epididymus, vas deferens, seminiferous tubules
mullerian duct derivatives
fallopian tubes(oviduct) , uterus, cervix
vas deferens
allows sperm and urine out of the body
seminiferous tubules
-made of serotoli cells house and nurture sperm to maturation
epididymus
holds mature sperm waiting to be ejaculated (lol)
SRY mechanism
sry maintains sf1 productio, together they activate sox0
leydig cells
make up testes, secrete testosterone
serotoli cells
make up the seminiferous tubules, secrete anti mullerian hormone
sperm: early methylation, but late proliferation and meiosis (doing mitosis for many years)
egg: late methylation but ealy proliferation and paused at prophase of meisosi 1 at birth
females do some of their imprinting and DNA methylation during each cycle (during follicular maturation) but megin meiosis before birth!
