Question

Six carbon atoms that enter the Calvin cycle as carbon dioxide flow through the cycle.

A) True
B) False
C) Maybe
D) Unknown

Answer 1

False. Carbon dioxide enters the Calvin cycle as a 5-carbon molecule called ribulose bisphosphate (RuBP). It takes six turns of the Calvin cycle to synthesize one molecule of glucose.

Step-by-step explanation:

False.

In the Calvin cycle, carbon dioxide enters as a 5-carbon molecule called ribulose bisphosphate (RuBP), not as individual carbon atoms. Each turn of the Calvin cycle fixes one carbon dioxide molecule and generates two molecules of glycerate 3-phosphate (3-PG). But it takes six turns of the Calvin cycle to synthesize one molecule of glucose, which contains six carbon atoms.