The electron transport chain, also known as the oxidative phosphorylation pathway, consists of four protein complexes and integrates redox activities to create an electrochemical gradient that leads to the production of ATP.
Both photosynthesis and cellular respiration take place in the mitochondria.
The third protein complex in the electron transport chain is Q-cytochrome c oxidoreductase, sometimes referred to as the III complex.
It catalyzes the transfer of electrons from reduced coenzyme Q (ubiquinol) to cytochrome c and completes the electron transport chain by transferring the electrons to the complex IV.