Which of the following processes generates a proton-motive force in mitochondria?
A) the flow of protons through ATP synthase down their concentration gradient
B) the reduction of NAD⁺ by the first electron carrier in the electron transport chain
C) lowering of pH in the mitochondrial matrix
D) pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space

Question

Quizplus · Accepted Answer

The pumping of hydrogen ions (protons) from the mitochondrial matrix across the inner membrane and into the intermembrane space generates a proton-motive force. This force is used to drive the synthesis of ATP through the flow of protons back into the matrix through ATP synthase. The other options listed are steps in mitochondrial energy production, but do not directly generate the proton-motive force.

Which of the Following Processes Generates a Proton-Motive Force in Mitochondria