Dark Reaction Nomenclature: Light Independence — NEET Biology
📚 Practice ConceptCan we, hence, say that calling the biosynthetic phase as the dark reaction is a misnomer? Discuss this amongst yourselves.
Which of the above statements are correct? S1: NADPH is primarily formed during non-cyclic photophosphorylation and functions as a key reducing agent in the biosynthetic phase of photosynthesis. S2: The chemiosmotic hypothesis explains that ATP synthesis is driven by a proton gradient where H+ ions accumulate in the stroma, leading to their diffusion into the thylakoid lumen through ATP synthase. S3: For the fixation of one molecule of CO₂ in the Calvin cycle, the energy requirement is two molecules of ATP and two molecules of NADPH. S4: Cyclic photophosphorylation exclusively involves Photosystem I, resulting in the production of ATP but not NADPH, specifically when light wavelengths beyond 680 nm are available. S5: The ATP produced during the light reaction is utilized in the Calvin cycle for the carboxylation of RuBP and the reduction of 3-PGA, but not for the regeneration of RuBP.
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