The fetal layer of the placenta on the other hand is called the chorion, which is a tissue that has fingerlike projections called chorionic villi which contain tiny fetal arterioles and venules.

胎盘的“胎儿层”也被称为；这是一有这手状突起的组织，富含微小的胎儿动脉和静脉。

But the placenta -- the organ that provides material to the embryo from the mother -- is actually formed from the chorion and allantois membranes of the egg.

是胎盘——为母亲的胚胎提供物质的器官——实际上是由卵子的和尿囊形成的。

Because, the main membranes of an amniotic egg -- known as the sac, the chorion, and the allantois -- are all present in animals that give birth to live young.

因为，羊卵的主要——被称为囊、和尿囊——都存在于生下活幼仔的动物身上。

Her belly is pretty big, so it's harder sometimes to know those things, unless you are able to see what we call the chorion, which is the separation between the two sacs.

她的肚子很大， 所以有时很难知道这些东西，除非你能看到我们所说的，也就是两个囊之间的分隔。