(electron transport chain and atp synthase)which of the four complexes pump protons out of the mitochondrial matrix? complexes i, ii, and ivcomplexes i, ii, and iiicomplexes i, iii, and ivall four complexes pump protons out of the mitochondrial matrix.

All four complexes pump protons out of the mitochondrial matrix

Explanation:

What differs are the biochemical processed by which each complex pumps out the protons. Only ATP synthase pumps proton from the intermembrane space to the matrix. This is as it harnesses the proton motive force, created by the other complexes, to generate ATP molecules.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

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