How many turns of the Calvin cycle yield one molecule of glucose?

Explanation

The Calvin cycle is integral to photosynthesis, as it incorporates carbon dioxide into organic molecules. Each turn of the cycle fixes one carbon dioxide molecule, contributing one carbon atom. Glucose, a hexose sugar, has a six-carbon structure. Therefore, it takes six turns of the Calvin cycle to fix enough carbon to form one glucose molecule. Option B is correct because it accounts for the necessary carbon fixation. Option A is incorrect, as four turns only fix four carbon atoms. Option C is incorrect, as eight turns result in excess carbon fixation. Option D is incorrect because two turns only produce G3P, not a complete glucose molecule.