And through the inner cavity we have that stock that is made up of this red structure as well as this blue structure as we see in this particular diagram. Now, what's the function of this gamma epsilon central stock? Well, the GAM epsilon central stock will essentially connect this structure shown in orange to this structure here. And as that stalk basically rotates it will cause the catalysis of the ADP and the orthophosphate to form the ATP molecules and the subsequent release of those ATP molecules into the matrix of the mitochondria. So once again the GAM epsilon central stalk will interact with the hexamer ring. As the stalk rotates it stimulates the synthesis and the release of ATP molecules and we'll discuss the details of that in a future lecture.