And what the placenta allows the fetus to do is basically excrete those wasteful byproducts to the mother that can ultimately excrete those products to the surrounding environment. It also plays a role in immunity and that means it can actually fight off infections. And finally we have this endocrine ability of the placensa to basically produce hormones and release those hormones into the bloodstream. And in this lecture we're going to focus on the endocrine capabilities of the placenta's. So we're going to focus on six different types of hormones that are produced and released by the placenta. Now previously we discussed two of these hormones.