Reproduction : The Placenta - Structure & Function

The ___ is a ___ structure composed of ___ ( ____ ) and ___ membrane tissues, where the ___ and ___ blood circulations are brought very close together over a ___ surface area, but do not mix.

___ and ___ are connected by ___ and a ___ in the ___. Exchange in the placenta takes place via ___ and ___.

Movements across the placenta involve :

The placenta is ___ bacteria, although ___.