Placental Development Flashcards
Capacity ion of the sperm happens in the female reproductive tract. What does this involve?
- Removal of some epididymal and seminal glycoproteins
- increase in membrane permeability of Ca
- Ca influx maximizes cAMP, increases sperm motility
What 3 things need to happen for fertilization once the sperm finds the egg?
- bind to Zona Pellucida via SP3
- Acrosomal reaction, release hydrolytic enzyme so it can penetrate Zona Pellucida
- Sperm and egg fusion
What are the 2 main enzymes released during the acrosomal reaction?
Neuramidase and acrosin
What happens in the cortical reaction after a sperm binds to the egg to prevent polyspermy?
Cortical granules present in the egg remove oligosaccharides from ZP3 and partially cleave ZP2, essentially destroying the receptors
What is another IG superfamily protein couple on the sperm and egg that is necessary for them to fuse?
Izumo on the sperm binds to CD9 on the egg
The slow component of the cortical reaction is the granule release. What is the fast component?
Change in Resting potential of oocyte plasma membrane that prevents further binding of sperm
What does the syncytiotrophoblast secrete to tell the corpus Luteum to secrete estrogen and progesterone?
Human chorionic gonadotropin (hCG)
What is tested for in a pregnancy test?
-hCG
What is the chorion made up of?
Syncytiotrophoblast, cytotrophoblast, and a layer of extraembryonic mesoderm
What is the maternal portion of the placenta called?
Decidua basalis
What is the embryonic portion of the placenta called?
Chorion frondosum
What makes up the Placental Barrier?
1: syncytiotrophoblast
2: Cytotrophoblast
3: extraembryonic mesenchyme
4: fetal endothelium
Where does fertilization happen?
Ampulla of uterine tube
