In oxidative phosphorylation, what is the primary purpose of the electron transport chain (ETC) in the inner mitochondrial membrane?
A
To directly catalyze the phosphorylation of ADP to ATP by substrate-level phosphorylation
B
To oxidize glucose to pyruvate in the mitochondrial matrix
C
To use energy from electron transfer to pump protons (H) across the inner mitochondrial membrane, generating a proton-motive force that drives ATP synthesis
D
To transport ATP out of the mitochondrial matrix by moving it through Complex IV
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검증된 단계별 안내
1
Understand the role of the electron transport chain (ETC) in oxidative phosphorylation, which occurs in the inner mitochondrial membrane.
Recognize that the ETC consists of a series of protein complexes (Complexes I-IV) that transfer electrons derived from NADH and FADH2 to molecular oxygen.
Know that as electrons move through these complexes, energy is released and used to pump protons (H\+ ions) from the mitochondrial matrix into the intermembrane space, creating a proton gradient.
This proton gradient, also called the proton-motive force, stores potential energy across the inner mitochondrial membrane.
Finally, this proton-motive force drives ATP synthesis by allowing protons to flow back into the matrix through ATP synthase, which catalyzes the phosphorylation of ADP to ATP.