PEP is the CO₂ receptor in which plants?

Options

(a) C₁
(b) C₂
(c) C₃
(d) C₄

Correct Answer:

C₄

Explanation:

CO₂ in C₄ plants (sugarcane, maize) combines with a 3-carbon compound phosphoenol pyruvate (PEP) to form 4-carbon compound oxaloacetic acid. This reaction is catalysed by PEP carboxylase and occurs in mesophyll cells.