Now, in which processes do we actually form our NADH and how is it exactly used to synthesize our ATP molecules? Well, NADH molecules are formed in glycolysis, which takes place in the cytoplasm of the cell. And NADH molecules are also formed in pyruvate decarboxylation and in the citric acid cycle, also known as the crept cycle, which takes place in the mitochondrial matrix. Now, once we form our NADH molecules, those NADH molecules then travel to the electron transport chain. Now, the electron transport chain is found in the inner phospholipid bilayer membrane of the mitochondria that is shown on the board. So we have the mitochondrial matrix, we have the inner membrane, the intermembrane space, and our outer mitochondrial membrane that is not shown, which is found somewhere here.