And the placenta plays a role in exchanging the nutrients, the oxygen and the waste products between that developing fetus, developing embryo and that mother. So these are the two functions of the Corian. Now let's move on to the embryonic membrane, the extra embryonic membrane that actually encloses that fetus itself. This is known as the emeon. So the Emeon is an extra embryonic membrane that directly surrounds that developing embryo. And in this diagram, the Emeon is this blue structure here.