AP BIOLOGY

Detailed explanation-1: -Complex III – 4 protons pumped/pair of electrons.

Detailed explanation-2: -Complexes I and III each transfer four protons across the membrane per pair of electrons. In complex IV, two protons per pair of electrons are pumped across the membrane and another two protons per pair of electrons are combined with O2 to form H2O within the matrix.

Detailed explanation-3: -mitochondrial matrix. 6. During electron transport, protons are pumped out of the mitochondrion at each of the major sites except for: Complex I.

Detailed explanation-4: -Complex III of the electron transport chain, also known as Q-cytochrome c oxidoreductase or simply cytochrome reductase, is a multi-subunit structure that functions to accept electrons from ubiquinol and transfer them onto another electron carrier called cytochrome c.