Question

Which one of the following is incorrect about the activities associated with PS-I and PS-II in non-cyclic photophosphorylation?

• A. Water is oxidised in PS - II, but not in PS - I.
• B. Photons (light) are needed to activate both PS - I and PS-II.
• C. Photolysis of water, formation of ATP $+ NADPH + H$ occur.
• D. Production of NADPH $+ H ^{+}$is associated with PS - II, but not with PS - I.

Answer 1

Answer: (C)

Photosystem (PS) - I and II are two pigments system of light reaction. Non-cyclic photophosphorylation is the light-requiring part of photosynthesis in higher plants, in which an electron donor is required, and oxygen is produced as a waste product. It consists of two photoreactions, resulting in the synthesis of ATP and $NADPH _2$. The hydrogen needed for the reduction of NADP (nicotinamide adenine dinucleotide phosphate) is made available from the breakdown of water.