Electrons cannot be passed translocated at the same time. The through unless the protons are used to force by the passage of the electron pair from the protons across the inner membrane is released coenzyme Q. The electrons are then passed through complex ill, where more protons are forced complex M, where still more protons are forced Complex IV, called cytochrome across, and oxidase, uses the energy it receives along with an electron pair to reduce oxygen to water. Note that since molecular oxygen is diatomic it takes two complexes, two electron pairs, and four hydrogen ions to complete the reaction