The final stage, oxidative phosphorylation, generates the majority of ATP - approximately 32 molecules per glucose molecule. It consists of the electron transport chain and chemiosmosis. During this stage, electrons carried by NADH and FADH2 are passed along a series of protein complexes, leading to the pumping of protons across the mitochondrial membrane, creating a gradient. This gradient powers ATP synthase, an enzyme that catalyzes the synthesis of ATP.