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Moderate

Mechanism of the Electron Transport Chain

APBIO-YQEY4W

The electron transport chain (ETC) transfers electrons between molecules in a series of oxidation-reduction reactions to generate a difference in pH across the thylakoid membrane.

How is the energy generated through electron transfer used to establish the pH gradient?

A

From the formation of molecular oxygen through the acceptance of electrons at the end of ETC.

B

From water being split in Photosystem I.

C

By powering the movement of protons into the thylakoid space.

D

By the transfer of $CO_2$ into the stroma.