Question

Which one of the following is not true about the light reaction of photosynthesis?

• A. Light energy provides energy for the photolysis of water through excitation of the reaction center of PS-II.
• B. The flow of electrons from water to NADP in non-cyclic electron transport produces one ATP.
• C. Reaction of the two photosystem are needed for the reduction of NADP.
• D. $P_{680}$ and $P_{700}$ are the reaction centers of PS-I and PS-II respectively.
• E. NADPH is not produced in cyclic electron transport in light reaction.

Answer 1

The correct option is D $P_{680}$ and $P_{700}$ are the reaction centers of PS-I and PS-II respectively.

Photosystem I has the reaction centre as P${}_{700}$. Photosystem II has reaction centre as P${}_{680}$. In the cyclic photophosphorylation only PS I is used while in Non-cyclic Z-scheme both PS II and PSI is involved. PS II receives the electron by photolysis of water while ferredoxin is the ultimate electron provider to PS I.

So, the correct answer is option D.