Question

Ribulose diphosphate carboxylase enzyme, catalyze the carboxylation reaction between
A) $CO_2$ 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

Carboxylation is a chemical reaction that produces carboxylic acid. The first carboxylation reaction involves the reaction of carbon dioxide with ribulose.

Complete answer:
Option A) $CO_2$ and $ribulose - 1$,$5 - diphosphate$: Ribulose diphosphate carboxylase enzyme, catalyze the carboxylation reaction between $CO_2$ and $ribulose - 1$,$5 - diphosphate$.
Photosynthesis
Comprises light and dark phases. The first stage of carboxylation involves the interaction of carbon dioxide with ribulose. They react together to generate two molecules of phosphoglyceric acid.
Option B) Oxaloacetic acid and acetyl $Co - A$: This is the initiating step of the citric acid cycle. The citric acid cycle occurs when a four-carbon compound (Oxaloacetic acid) condenses with acetyl $Co - A$ to form citric acid.
Option C) PGA and dihydroxyacetone phosphate: PGA and dihydroxyacetone phosphate in this process ribulose diphosphate carboxylase enzyme is not the catalyst. Dihydroxyacetone phosphate is important in the lipid biosynthesis process.
Option D) Ribulose diphosphate and phosphate glyceraldehyde: The catalyst in this process is not Ribulose diphosphate carboxylase enzyme. Ribulose diphosphate synthesis phosphoglycerate. And phosphate glyceraldehyde is also known as triose phosphate.

option A) $CO_2$ and $ribulose - 1$,$5 - diphosphate$.

Note:
In the initial, carboxylation comprises reaction between carbon dioxide and ribulose. They together produce two molecules of phosphoglyceric acid. There are two stages of photosynthesis: light and dark. During the light phase, solar energy is converted into chemical energy. And unlike light phase dark phase can happen in light and darkness light energy is captured by photosystem.