Now let's examine each one of these individual monomers. So we have this purple region found on the extracellular side and this is a region that contains a binding side for that EGF molecule. This brown section is that section that essentially spans the membrane and it anchors that molecule in that membrane. And this is the intracellular domain region found on the inside portion of the cell. And this is the region that contains the tyrannine protein kinase domain that will be responsible for initiating the first phosphorylation process as we'll see in just a moment. Now, this is the Seatile, the carboxyl terminal end of this polypeptide and we'll see why that's important in just a moment.