Question

NADP is converted into $NADP{{H}_{2}}$ in
(a)Photosystem-I
(b)Non-cyclic photophosphorylation
(c)Calvin cycle
(d)Photosystem-II

Answer 1

Hint: The conversion of NADP takes in the Z scheme. In the Z scheme, the electron transport chain helps establish electrochemical proton gradient by the involvement of both photosystems by absorbing light and excited electrons are emitted from the primary pigments of both photosystem reaction systems.

Complete answer:
Nicotinamide adenine dinucleotide phosphate (NADP) is a coenzyme used in the anabolic reaction, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent. Non-cyclic photophosphorylation is a two-stage process involving two different chlorophyll photosystems that occur on thylakoid membranes inside the chloroplast. When the highly excited electron is transferred to ferredoxin-NADP reductase or FNR which uses exciting electrons to catalyze the reaction-
$NAD{{P}^{+}}+2H+2{{e}^{-}}\to NADPH+{{H}^{+}}$

Additional Information:
-Plants and cyanobacteria utilize two photosystems that work sequentially to produce both energy and reducing power for the synthesis of sugar in the Calvin cycle.
-The result of the non-cyclic electron flow is that water is oxidized to yield hydrogen ion, electron, and oxygen.
-Cyclic photophosphorylation of electron flow produces ATP but no NADPH or oxygen. In a cyclic electron, the flow electron passes to ferredoxin and moves back through the cytochrome bf complex to plastocyanin.
-The concentration of NADPH in the chloroplast runs low on ATP for the Calvin cycle, NADPH will accumulate and the plant may shift from non-cyclic to cyclic electron flow.

So, the correct answer is ‘non-cyclic photophosphorylation.’

Note: -In non- cyclic electron flow photosystem-I is the more primitive system and cannot produce ATP.
-In non- cyclic electron flow photosystem-II replaces the electron displaced by photosystem- I and gets its electron from water.