Which enzyme in the photosynthetic Z scheme catalyzes the PQ cycle,which is analogous to Complex III and the Q cycle in the mitochondrial electron transport chain? A) photosystem II B) plastocyanin C) cytochrome b₆f D) photosystem I

Question

Quizplus · Accepted Answer

The cytochrome b₆f complex, also known as the cytochrome b6f complex, performs the PQ (plastoquinone) cycle in the photosynthetic Z scheme. This process is similar to the Q cycle in the mitochondrial electron transport chain and is responsible for transferring electrons from PQH2 to plastocyanin (PC) and ultimately to photosystem I. Photosystem II is responsible for the initial step of capturing light energy, while photosystem I is involved in the final step of producing NADPH. Plastocyanin is involved in transferring electrons from the cytochrome b6f complex to photosystem I but is not directly involved in the PQ cycle.

Which Enzyme in the Photosynthetic Z Scheme Catalyzes the PQ