Photosynthesis Question 87

87. The enzyme that catalyses carbon dioxide fixation in $C_4$ plants is

[1992]

(a) RuBP carboxylase

(b) PEP carboxylase

(c) Carbonic anhydrase

(d) Carboxy dismutase

Show Answer

Answer : b

Hints & Solution

(b) In $C_4$ plants, the primary acceptor of $CO_2$ is phosphoenol pyruvate. It combines with carbon dioxide in the presence of PEP carboxylase to form oxaloacetic acid in mesophyll cells.