In photosynthesis, the set of reactions that use nadph and atp formed in the light-capturing reactions to drive the fixation of co2, reduction of the fixed carbon to produce sugar, and the regeneration of the substrate used to fix co2.

The correct answer will be- light independent reaction or Calvin cycle

Explanation:

The process of photosynthesis takes place in the two phases: light-dependent and light-independent phase.

The light-dependent phase form NADPH  and NADPH which are utilized during the light-independent phase to synthesise glucose molecule.

The light-independent phase occurs in the cytosol or stroma of the chloroplast in dark conditions which help synthesize the glucose molecules. The light-independent reaction is also known as the Calvin cycle which forms the glucose molecules in three steps- carboxylation, reduction and regeneration.

Thus, the Calvin cycle is the correct answer.

it has one origin of replication, but it proceeds in two directions - d)

1) a

2)c

3)a

4)c

5)b

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