Dark Reactions: Calvin Cycle and C3 Pathway · NCERT Biology

If a C3 plant is provided with CO2 containing 14C, which molecule would show radioactivity first?

  1. Glucose
  2. 3-phosphoglycerate
  3. Ribulose bisphosphate
  4. Phosphoenolpyruvate
Show answer and explanation

Correct answer: 3-phosphoglycerate

As 3-phosphoglycerate (3-PGA) is the very first stable product formed after CO2 fixation in C3 plants, it would be the first molecule to incorporate the radioactive 14C.

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