1. The "proton flow" of ATP-ETC coupling. An explanation for the coupling of ATP synthesis with electron transport chain reactions
2. The result of pumping of protons in the mitochondrial matrix across the inner mitochondrial membrane is a higher concentration of protons in the intermembrane membrane space than in the matrix. This concentration difference constitutes an electrochemical (proton) gradient.
3. A spontaneous flow of proton from the region of high concentration to low occurs because of the gradient.
4. ATP synthase has 2 subunits F° and F¹. The F° part of the synthase is the channel for proton flow, whereas the formation of ATP occurs in F¹ subunit.
5. The ATP produced through oxidative phosphorylation must be moved from the matrix back to the intermembrane space before it can be used for metabolic reactions.