And this GTP bound protein is attached onto the adenolate cyclist. Now, the A chain catalyzes the addition of an ADP ribosemoidi onto the arginine residue found on this g protein in the GTP phase. And so this covalent modification of that g protein in the GTP phase stabilizes the structure of the GTP phase. And so this structure will not be able to turn itself off and that traps it in its active state. And so if we move on to this region here, we see that the Galpha protein will be trapped in the active state, which implies that it will continually stimulate the cyclic Amp production, which in turn stimulates the activity of the protein kinase A. And protein kinase A does two important things.