According to the chemiosmotic theory of how oxidation and phosphorylation are coupled, which of the following processes produces the chemical gradient that drives the generation of ATP from ADP?
A) electron transport causes H+ to penetrate the inner mitochondrial membrane
B) electron transport ejects H+ into the intermembrane space
C) FADH2 is regenerated from FAD
D) NADH is regenerated from NAD+
E) osmotic forces cause H+ to bind with FAD in the mitochondrial matrix

Question

Quizplus · Accepted Answer

Electron transport ejects H+ into the intermembrane space, creating a proton gradient that drives ATP synthesis.  The normal flow of electrons, through the proteins of the oxidative phosphorylation machinery, is coupled with the establishment of a proton gradient across the inner mitochondrial membrane. As electrons flow from one complex to another the energy released is used to pump protons out of the matrix into the inner membrane space. The establishment of this proton gradient is the chemiosmotic potential that is coupled with the production of ATP.

According to the Chemiosmotic Theory of How Oxidation and Phosphorylation