Question

Give a summary of each complex that brings electrons to oxygen for oxidative phosphorylation. Be sure to give how many protons are pumped into the intermembrane space for each complex.

Answer 1

The electron transport chain (ETC) is composed of four complexes that bring electrons to oxygen for oxidative phosphorylation. Complex I (NADH dehydrogenase) pumps 4 protons into the intermembrane space. Complex II (succinate dehydrogenase) does not pump any protons into the intermembrane space. Complex III (cytochrome c reductase) pumps 4 protons into the intermembrane space. Complex IV (cytochrome c oxidase) pumps 2 protons into the intermembrane space.