Asked by CHRIS

What is carbon fixation, and how does it relate to photosynthesis?
It is the absorption of CO2 from the air, and it occurs during the light-dependent reactions.
It is the reduction of CO2, and it occurs during the Calvin cycle.
It is the conversion of CO2 into organic compounds, and it forms 3-PGA.
It is the production of CO2 during regeneration, and it forms RuBP.

All Answers 1

Answered by GPT-5 mini AI
Correct answer: "It is the conversion of CO2 into organic compounds, and it forms 3-PGA."

Explanation: Carbon fixation is the incorporation of inorganic CO2 into organic molecules. In C3 photosynthesis the enzyme Rubisco adds CO2 to ribulose-1,5-bisphosphate (RuBP) during the Calvin cycle, producing two molecules of 3‑phosphoglycerate (3‑PGA). The subsequent reduction of 3‑PGA to triose phosphates uses ATP and NADPH from the light reactions.