Which of the Following Best Describes the Proton-Motive Force

Question

Which of the following best describes the proton-motive force?
A)a higher concentration of protons in the intermembrane space compared to the mitochondrial matrix
B)a higher concentration of protons in the mitochondrial matrix compared to the intermembrane space
C)a higher concentration of protons in the cytosol compared to the mitochondrial matrix
D)a higher concentration of hydrogen atoms in the intermembrane space compared to the mitochondrial matrix
E)a lower pH inside the mitochondrial matrix compare to the cytosol

Accepted Answer

The proton-motive force refers to the electrochemical gradient of protons (H+) across the inner mitochondrial membrane, which is generated by the pumping of protons across the membrane during the electron transport chain. As a result, there is a higher concentration of protons in the intermembrane space compared to the mitochondrial matrix. This gradient of protons represents a form of potential energy that can be harnessed to generate ATP through ATP synthase. Thus, option A is the correct answer.