Question

Ribulose diphosphate carboxylase enzyme, catalyse the carboxylation reaction between

• A. $C{O}_2$ and ribulose-1, 5-diphosphate
• B. Oxaloacetic acid and acetyl Co-A
• C. PGA and dihydroxyacetone phosphate
• D. Ribulose diphosphate and phosphate glyceraldehyde

Answer 1

The correct option is A $C{O}_2$ and ribulose-1, 5-diphosphate

Photosynthesis comprises of light phase and dark phase. During light phase reducing power and assimilatory powers are synthesized, which are used in the dark phase to reduce carbon dioxide to carbohydrates. The dark phase comprises of initial carboxylation reaction, reduction of phosphoglyceric acid to phosphoglyceraldehyde and synthesis of carbohydrates and regeneration of ribulose 1,5 bisphosphate from phosphoglyceraldehyde. The initial carboxylation comprises of reaction between carbon dioxide and ribulose 1,5 bisphosphate to generate two molecules of phosphoglyceric acid. This reaction is catalyzed by ribulose 1,5 bisphosphate carboxylase oxygenase (RuBisCO) enzyme.