Answer: Oxaloacetate (4-carbon compound).
- A PGA, a 3-carbon compound formed via the Calvin cycle
- B Oxaloacetate (4-carbon compound)
- C Sucrose, synthesized directly within mesophyll cells
- D RuBP, regenerated during the Calvin cycle
Correct answer: B. Oxaloacetate (4-carbon compound)
Explanation: C<sub>4</sub> plants first fix CO<sub>2</sub> into oxaloacetate (4-carbon) in mesophyll cells via PEP carboxylase, then transfer CO<sub>2</sub> to bundle sheath for Calvin cycle.
Simplified photosynthesis diagram: light energy, CO2, and H2O enter the leaf and are converted in the chloroplast into glucose and O2.
Concept context
Light reactions, the Calvin cycle, C 3 /C 4 /CAM pathways, photorespiration, and factors affecting the rate of photosynthesis. One of the highest-yield NEET chapters.