College

Which compound is produced during carbon fixation?

A. PGA
B. G3P
C. RuBP
D. C6H12O6

Answer :

During the process of carbon fixation in photosynthesis, carbon dioxide (CO2) is incorporated into organic molecules. The Calvin cycle is a key part of this process, and it occurs in the chloroplasts of plant cells.

Here's a step-by-step explanation:

1. CO2 Involvement: Carbon fixation begins when CO2 in the atmosphere is captured.

2. Role of RuBP: Ribulose bisphosphate (RuBP) is a 5-carbon sugar that acts as the acceptor for CO2.

3. Catalysis by Rubisco: The enzyme RuBisCO catalyzes the reaction between CO2 and RuBP. This forms an unstable 6-carbon intermediate.

4. Formation of PGA: The unstable 6-carbon intermediate quickly breaks down into two molecules of 3-phosphoglycerate (PGA), a 3-carbon compound. This is the first stable compound formed during carbon fixation.

Hence, the compound produced during carbon fixation is PGA.