Question

multiple choice question
which component of the aerobic respiration pathway acts as a proton pump that removes h+ from the mitochondrial matrix and pumps it into the space between the inner and outer mitochondrial membranes?
glycolysis
the citric acid cycle
the electron - transport chain
the matrix reactions

Explanation:

In aerobic respiration, the electron - transport chain is composed of protein complexes embedded in the inner mitochondrial membrane. As electrons are passed through these complexes, protons ($H^+$) are pumped from the mitochondrial matrix into the inter - membrane space, creating a proton gradient. Glycolysis occurs in the cytoplasm and does not directly pump protons in the mitochondria. The citric acid cycle occurs in the mitochondrial matrix and generates electron carriers but does not act as a proton pump in the described way. Matrix reactions in general do not function as proton pumps for the purpose of creating the proton - motive force across the inner mitochondrial membrane.

Answer:

The electron - transport chain