chorion or allantois develop into placenta?

[wantVCUdental]

Advertisement - Members don't see this ad

According to AP cliffs chorion is for gas exchange and later develops in to placenta and that allantois is initially for gas exchange but fuses with chorion
On KBB, it says allantois is the one that is involved in gas exchange and later forms placenta
is KBB wrong?

 

[bebebebebebe]

I think both are fetal part of placenta.Maternal part of placenta is Endometrial epithelial and CT as we know

Chorion:the outermost layer of fetal membranes derived from trophoblast which is the main part of placenta

Allantois: is incorporated into umbilical cord of placenta

That's my opinion. I might be wrong

 

[americanpierg]

According to AP cliffs chorion is for gas exchange and later develops in to placenta and that allantois is initially for gas exchange but fuses with chorion
On KBB, it says allantois is the one that is involved in gas exchange and later forms placenta
is KBB wrong?

The allantois forms part of the placenta, if it says it forms the whole placenta then it is wrong. The placenta comprises mostly of the chorion from the baby's side, which makes sense since the chorion is bascially the outer envelope.