Question

Which one of the following statements correctly describes cyclic photophosphorylation?

• A. Cyclic photophosphorylation involves both PS-I and PS-II
• B. Cyclic photophosphorylation produces neither ATP nor $NADPH+H^{+}$
• C. Water is the ultimate source of e- in cyclic phosphorylation
• D. There is cyclic flow of electrons

Answer 1

The correct option is D There is cyclic flow of electrons

In cyclic photophosphorylation, only PS-I is involved. The electrons released from PS-I are cycled back to the same photosystem. Hence, the source of electrons is not water in cyclic photophosphorylation. ATP is synthesised during cyclic photophosphorylation but NADPH + H+ is not synthesised.