How many times must the Calvin cycle turn to yield a single molecule of glyceraldehydes-3-phosphate (G3P).
A) 2
B) 3
C) 4
D) 5
E) 6

Question

Quizplus · Accepted Answer

The Calvin Cycle must turn 3 times to produce a single molecule of G3P. During each cycle, 3 molecules of CO2 combine with 3 molecules of RuBP to form 6 molecules of 3-phosphoglycerate (3PG). Through a series of enzyme-catalyzed reactions, the 6 molecules of 3PG are converted into 6 molecules of G3P. However, only one of the 6 molecules of G3P is released from the cycle to be used for the synthesis of glucose, while the other 5 molecules are recycled back into the cycle to regenerate RuBP. Thus, it takes 3 cycles of the Calvin Cycle to produce one molecule of G3P, which is ultimately used for glucose synthesis.

How Many Times Must the Calvin Cycle Turn to Yield