So basically in this step we conclude the following the binding of the EGF molecules onto these binding sides basically causes this dimerization process to actually take place. And what that leads to is the cross phosphorylation of these C terminal tails on both of these sides. And what this cross phosphorylation process actually does is it creates attachment points for further attachment of other proteins as we'll see in just a moment. So the entire point of these regions is to basically allow the attachment of other important proteins that are part of the EGF signal transduction pathway. And to see what we mean by that, let's take a look at the following diagram. So we can see that there are many different types of proteins and enzymes involved in this process.