What is the total number of ATP and NADPH molecules required to synthesize one molecule of glucose during the biosynthetic phase in a maize plant?

Step-by-step solution

Maize is a C₄ plant. In the C₄ pathway, the fixation of one CO₂ molecule requires 5 ATP (3 ATP for the Calvin cycle in the bundle sheath cells and 2 ATP for the regeneration of PEP in the mesophyll cells) and 2 NADPH. To synthesize one molecule of glucose, 6 molecules of CO₂ must be fixed. Therefore, the total energy requirement is 6 5 = 30 ATP and 6 2 = 12 NADPH. Option 1 represents the requirement for a C₃ plant, which lacks the additional ATP cost for PEP regeneration. Answer: 30 ATP and 12 NADPH