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. We discussed progesterone and estrogen. So these two hormones are basically steroid hormones and what that means is they're lipid soluble, they cannot dissolve in the blood and so they need a protein carrier. And because they're lipid soluble, they can easily cross the plasma membrane of the target cell, which means they bind onto protein receptors found inside our cell.