fertility and early development Flashcards
what is syngamy?
where sperm and egg hit/meet/come together
where does syngamy and fertilisation occur?
in AMPULLA of fallopian tube
what is acrosome reaction?
coating of head/acrosome changes allowing sperm to penetrate zona pallucida, allowing to fuse with oocyte membrane.
where do gonads develop?
gonadal ridges - form on posterior abdominal wall
what can change sperm motility ?
level of K+
what determines sex of offsrping?
Y bearing sperm determines sex at time of conception
how does oogonia transform into oocyte?
by meiosis inducing substance (MIS) (from mesonephric duct)
what substances does male produce?
MIS and meiosis preventing substances (MPS) which counteracts MIS. (AMH)
where are MIS and MPS (AMH) released from?
MIS- mesenephric duct
MPS - testes cords
where/what is testes determining gene?
SRY gene. on Y chromosome (induces testes formation)
what is AMH and where is it produced?
Anti-mullarian hormone - produced in testes along with testosterone
what happens to SOX9 levels in males and females?
females - SOX 9 levels decrease
male - SOX9 levels increase (in sertoli cells) (few days after SRY activated)
what duct degenerates in male and female?
in female - mesonephric duct degenrates
in male - paramesonephric duct degenerates
what is testicular feminism syndrome?
where there is male genotype but female phenotype.
46XY
how is testicular feminism sndrome caused?
normal levels of testosterone produced BUT are low levels of cytosolic carrier protein - prevents testosterone action.
