How many ATP and NADPH molecules will be required to make one molecule of glucose through the Calvin pathway?

For synthesis of 1 glucose molecule (C₆H₁₂O₆):

Requirement:6 turns of Calvin cycle (fixing 6 CO₂ molecules)

Energy consumption per turn:

• 3 ATP molecules (2 for reduction, 1 for regeneration)
• 2 NADPH molecules (for reduction phase)

Total for 1 glucose:

• 18 ATP molecules (6 × 3)
• 12 NADPH molecules (6 × 2)

Breakdown by phase:

Calvin Cycle Phase	ATP Used	NADPH Used
Carboxylation	0	0
Reduction	12	12
Regeneration of RuBP	6	0
Total	18	12