On the inside portion, of that structure. So we have an alpha domain, a beta domain, and a gamma domain. Now, the alpha domain is actually a g protein itself. And what that means is it binds guanial nucleotides such as GDP and GTP. Now, before the epinephrine actually binds, the alpha domain contains a GDP, a guanosine diphosphate. And when the guanosine diphostate is bound to that alpha domain, the alpha domain has a very high affinity for the seven TM domain and these other two domains.