Pregnancy and Placentation Flashcards
4 placental fetal membranes
Yolk sac, amnion, chorion, allantois
Amnion
Membrane immediately surrounding the fetus and encloses the amniotic cavity
Amniotic cavity
Filled with fluid to provide physical support to the fetus
Choriovitelline
Marsupials
Choriovitelline then Chorioallantoic
Horse, carnivore, feline
Chorioallantoic
Ruminants, pigs, humans
Functional unit of placenta
Chorionic villus
Discoid
Disk shape. Making contact with just one part of the uterine wall. Humans and rodents
Cotyledonary
Attached to maternal caruncles and then form the placate. Ruminants
Zonary
A band around the fetus. Dogs, cats, foxes.
Diffuse
Through the entire uterine surface for exchange. Equine and pigs.
Invasive implantation
Conceptus breaks through the surface endometrium
Types of invasive implantation
Interstitial and eccentric
Non-invasive
Epithelial integrity retained
Interstitial Invasive Implantation
Very deep invasion and surface epithelium restores
Eccentric Invasive Implantation
Stroma only partially invaded and conceptus continues to project into the lumen . Doesn’t completely implant in the wall
Animals with a non-invasive implantation
Cow, ewe, pig, mare
Animals with an invasive, eccentric implantation
Rodents, dogs, cats
Animals with invasive interstitial implantation
Humans
Interdigitation attachment point types
Folded, lamellar, villous
Folded interdigitation attachment points
Pig
Lamellar Interdigitation attachment points
Carnivores
Villous interdigitation attachment points
Equids, ruminants, humans, rodents
What does the blastocyst cause
The elongation of the fetus
