Electron carriers like FADH2 and NADH transfer electrons through proteins in the inner mitochondrial membrane until they reach O2, forming water. This process releases energy, which pumps H+ ions into the inner membrane space, creating a high concentration of protons. This triggers ATP synthesise to convert ADP to ATP through oxidative phoshorylation, producing about 34 ATP molecules. Overall, from glycolysis process to the electron transport chain, around 38 molecules are generated