PHOTOSYNTHESIS
THE CALVIN CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Reduction
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Regeneration
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Carbon Fixation
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Phosphorylation
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Detailed explanation-1: -In stage 1, the enzyme RuBisCO incorporates carbon dioxide into an organic molecule. In stage 2, the organic molecule is reduced. In stage 3, RuBP, the molecule that starts the cycle, is regenerated so that the cycle can continue. In summary, it takes six turns of the Calvin cycle to fix six carbon atoms from CO2.
Detailed explanation-2: -Stage 1: Fixation RuBisCO catalyzes a reaction between CO2 and RuBP. For each CO2 molecule that reacts with one RuBP, two molecules of 3-phosphoglyceric acid (3-PGA) form. 3-PGA has three carbons and one phosphate. Each turn of the cycle involves only one RuBP and one carbon dioxide and forms two molecules of 3-PGA.
Detailed explanation-3: -So the correct answer is ‘carboxylation’.
Detailed explanation-4: -ATP is used to convert some PGAL into more RuBP. What is carbon fixation? When carbon dioxide is combined with the RuBP to form the unstable 6-carbon compound.
Detailed explanation-5: -The carbon fixation process occurs during the light reaction phase of the Calvin cycle.