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Old 08-23-2015
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Default electron transport chain HELP!!!

Can someone explain why E is the answer. Wouldnt increasing the proton concentration in the matrix just decrease the gradient across the membrane and decrease the flow of electrons through the F0 channel, thus decreasing ATP synthesis?

QUESTION: Which of the following would be expected to increase the amount of ATP produced through operation of the electron transport chain and oxidative phosphorylation?

A. Application of respiratory uncouplers, such as thermogenin
B. Decreasing NADH levels
C. Decreasing the pH in the space between the inner and outer mitochondrial membranes
D. Increasing the permeability of the inner mitochondrial membrane to protons
E. Increasing the proton concentration in the mitochondrial matrix

The correct answer is E. The proton gradient drives and supplies the energy needed to phosphorylate ADP to ATP in the F1 compartment. The greater the gradient potential (more protons on the outside), the more energy is in the gradient and the more ATP can be synthesized.
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