Photosynthesis Question 29
29. In light reaction, plastoquinone facilitates the transfer of electrons from
(a) Cytb $ _6$ complex to PS-I
(b) PS-I to NADP
(c) PS-I to ATP synthase
(d) PS-II to Cytb $_6 f$ complex
Show Answer
Answer : d
Hints & Solution
(d) After excitement, $e^{-}$is passed from PS-II $(P _{680})$ to primary electron acceptor (Pheophytin). From primary $e^{-}$acceptor, $e^{-}$is passed to plastoquinone. Plastoquinone (PQ) in turn transfer its $e^{-}$to Cyt $b_6 f$ complex. Therefore plastoquinone facilitates the transfer of electrons from PS-II to Cyt $b_6 f$ complex. Plastoquinone (PQ) and ubiquinone (UQ) are two important prenylquinones, functioning as electron transporters in the electron transport chain of oxygenic photosynthesis and the aerobic respiratory chain, respectively, and play indispensable roles in plant growth and development through participating in the biosynthesis.
