Proton-motive Force (pmf): refers to ΔG stored in a proton gradient; has two components:
1. Chemical potential energy (ΔpH) - difference in H+ concentration across the membrane
2. Electrical potential energy (Δψ) -results from charge imbalance when H+ is transferred without a counter ion
Which of the following processes generates a proton-motive force in mitochondria?
a. The reduction of NAD+ by the first electron carrier in the electron transport chain.
b. The flow of protons through ATP synthase down their concentration gradient.
c. Pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space.
d. Lowering of pH in the mitochondrial matrix.