NEET Botany Question (2026) — Solution

Step-by-step solution

The Calvin cycle is the primary pathway for carbon fixation in plants. The first step of the Calvin cycle is carboxylation, where carbon dioxide is added to a five-carbon acceptor molecule, Ribulose-1,5-bisphosphate (RuBP). This reaction is catalyzed by the enzyme Ribulose bisphosphate carboxylase-oxygenase, commonly known as RuBisCO. Hexokinase is an enzyme involved in glycolysis. PEP carboxylase is the primary carboxylating enzyme in the C4 pathway. Carboxypeptidase is a proteolytic enzyme involved in digestion. Answer: RuBP carboxylase – oxygenase