Photosynthesis Question 39
39. In photosystem-1the first electron acceptor is
(a) Cytochrome
(b) Plastocyanin
(c) An iron-sulphur protein
(d) Ferredoxin
Show Answer
Answer : c
Hints & Solution
(c) In photosystem I or photoact I electrons released by P-700 are accepted by a substance of iron-sulphur-protein complex denoted as $A(FeS)$ which is thus reduced and it passes these high electrons to oxidised ferredoxin and it gets reduced. From reduced Fd these electrons are passed to FAD which is now reduced to $FADH_2$ and then electrons and hydrogen are accepted by NADP which makes $NADPH_2$. Here, photosystem I ends.