Question

Carboxylation in the C3 plants requires the following enzyme-

• A. Kinase
• B. RuBisCO
• C. Nitrogenase
• D. -ketoglutarate dehydrogenase

Answer 1

The correct option is B

RuBisCO

The correct option is B.

Explanation of the correct option:

1. In C3 plants, the Calvin cycle ( chemical reactions that take takes place during photosynthesis.) occurs in mesophyll cells.
2. Here carboxylation processes the first step of the Calvin cycle reaction.
3. It is the fixation of CO₂ into a stable organic form.
4. The carboxylation process is catalyzed by the enzyme RuBisCO.
5. CO₂ is utilized for carboxylation of RUBP.
6. RuBisCO enzyme then transforms it into 3- phosphogoglyceric acid.

Explanation of the incorrect option:

Option A:

1. The kinase is an enzyme that adds phosphate groups to other molecules.
2. Kinases are enzymes that are required during cell signaling.

Option C:

1. Nitrogenase is the main enzyme for biological nitrogen fixation.
2. The nitrogenase enzyme converts nitrogen to ammonia.

Option D:

1. Ketoglutarate dehydrogenase is an enzyme complex.
2. It plays an important role in the citric acid cycle.

Final answer: Carboxylation in the C3 plants requires the enzyme RuBisCO.