So this is a signal transduction pathway that we're going to focus on in this lecture. So we see that this pathway stimulates the growth and division. So processes like cell proliferation, cell division, cell growth, cell differentiation of these epidermal and epithelial cells. So let's begin by focusing on the actual structure of that protein receptor that binds the EGF molecules. And this is basically what it looks like here. So we have the cell membrane the outside and the inside of the cell.