embryogenesis Flashcards
what is an overview of the events of week 1
fertilization, formation of the blastocyst and the implantation of the blastocyst
what happens in week 2?
- embryoblast differenciation
- trophoblast differentiation
- placenta formation
when is the fetus most succeptible to a teratogen?
between weeks 1-8
where does fertilization happen?
in the ampulla where the oocyte and the sperm meet
whats the hormone that maintains the corpus luteum?
HCG
what secretes HCG?
trophoblasts of the placenta
what are the phases of fetilization
penetration of
corona radiata
zona pellucida
plasma membrane fusion
what is the feature of the oocyte that blocks polyspermy?
there are two steps.
- plasma membrane depolarises
- the cortical reaction- intracellular Ca2+ flux
what is the difference between blastomeres and morula?
blastomeres are two cell stage and morula is 32 cell
when does the polarity of the cells start? and what forms whichblast?
inner cell mass forms the embryoblast and the outer cell masss forms the trophoblast
what is significant about the inner cell mass?
they make pluripotent cells
implantation happens on what day
6 days after fertilization
what directs implantation and where do the cells come from?
trophoblast drives implantation and the cells are from the oter cell mass. implantation ends week 1
what develops from the epiblast vs. hypoblast vs. trophoblast?
epiblast- amniotic cavity
hypoblast- yolk sac and connecting stalk
trophoblast- fetal part of placenta
what cells migrate to the primitive streak to start gastrulation?
epiblast cells migrate to primitive streak to start gastrulation
if you are short on time here is the conclusion
