Question

H+ ions are pumped by which complexes?

1) Complex I, II, III, and IV
2) Ubiquinone
3) Cytochrome C

Answer 1

H+ ions are pumped by Complex I, II, III, and IV, as well as Ubiquinone (Q) and Cytochrome C.

Step-by-step explanation:

The H+ ions are pumped by Complex I, II, III, and IV in the electron transport chain. Complex III passes on electrons from coenzyme-Q (QH₂) to cytochrome c, and complex IV aids in the splitting of molecular oxygen (O₂) while pumping hydrogen ions to the intermembrane space. Ubiquinone (Q) receives electrons from complex I and complex II and delivers them to Complex III.