Question

Carbon dioxide acceptor in C3 plants is

• A. PGA
• B. PEP
• C. RuDP
• D. none of these.

Answer 1

The Correct Option is C

To solve the question of which compound acts as the carbon dioxide acceptor in C3 plants, we need to delve into the process of photosynthesis, specifically the Calvin cycle.

In C3 plants, the Calvin cycle is the set of chemical reactions that take place in chloroplasts during photosynthesis. This cycle is light-independent as it does not require sunlight to proceed. The cycle uses ATP and NADPH, produced by the light-dependent reactions, to convert carbon dioxide into glucose.

Now, let's examine the options provided:

1. PGA: PGA stands for 3-phosphoglyceric acid, which is an intermediate in the Calvin cycle, not the initial acceptor of carbon dioxide.
2. PEP: Phosphoenolpyruvate (PEP) is the primary CO₂ acceptor in C4 plants, not in C3 plants.
3. RuDP: RuDP stands for Ribulose-1,5-bisphosphate. This compound acts as the carbon dioxide acceptor in C3 plants. The enzyme RuBisCO catalyzes the fixation of CO₂ to RuDP, forming two molecules of 3-phosphoglycerate (3-PGA).
4. none of these: This option can be disregarded as RuDP is the correct answer.

Based on this analysis, RuDP is the correct answer since it is the carbon dioxide acceptor in the Calvin cycle of C3 plants.