And that allows the ATP synthase to actually use that energy that is stored in that proton gradient to generate these ATP molecules. So we conclude the following the oxidation of the fuel molecules in glycolysis and the citric acid cycle is actually coupled to the oxidative phosphorylation of the ADP to ATP by using this oxygen in protein complex four, by the establishment of this hydrogen ion gradient on the electron transport chain. So what we're ultimately doing in aerobic cell respiration is we're transforming one form of energy into a different form of energy, into a form that we can actually use by the cells of our body. So we basically transform the energy that is stored in the movement of electrons into the energy that is stored in the gradient that exists between the two sides as a result of the unequal distribution of H plus ions. And then we ultimately transform that energy into the energy that is stored in the chemical bonds of the ATP molecules because it's the ATP molecules which can be used by ourselves to carry out a variety of different types of processes. So the final thing that I'd like to focus on in this lecture is some facts that you should know about the mitochondrion found inside our cells.