Question

Which among the following is the initial acceptor of carbon dioxide during photosynthesis?

• A. Ribulose - 1,5 - bisphosphate
• B. Ribose - 5 - phosphate
• C. Ribulose - 5 - Phosphate
• D. Phosphoglyceric acid.

Answer 1

The correct option is A Ribulose - 1,5 - bisphosphate

In the Light dependent reaction or Calvin cycle, carbon atoms from carbon dioxide are incorporated into organic molecules and used to build carbohydrates.
This reaction can be divided into three main stages: carbon fixation, reduction, and regeneration of the starting molecule.
During Carbon fixation, a carbon dioxide molecule combines with a five-carbon acceptor molecule, ribulose-1,5-bisphosphate (RuBP) to form ​​​​​​​3-phosphoglyceric acid (3-PGA). ​​​​​​​This reaction is catalyzed by the enzyme RuBP carboxylase/oxygenase, or rubisco.