In the Calvin cycle, what is the first stable product formed when carbon dioxide combines with ribulose bisphosphate?
Answer and explanation
Correct answer: A. Two molecules of glycerate 3-phosphate (GP)
- Step 1: RuBisCO catalyses the reaction of CO2 with RuBP (5C). Step 2. The unstable 6C intermediate splits into two 3C GP molecules. Answer: Two molecules of glycerate 3-phosphate (GP). Why not the others: triose phosphate is made later using ATP and NADPH; pyruvate belongs to respiration; glucose is built from triose phosphate.
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