Question

Name any two $C_4$ plants. Describe how carbon dioxide is fixed in such plants.

Answer 1

Maize and wheat are the two examples of C₄ plants.

These plants do not follow the direct carbon fixation in the Calvin cycle like in C₃ carbon fixation. The C₄ pathway involves steps that first converts pyruvate to phosphoenolpyruvate (PEP) to bind with the CO₂ forming a four-carbon compound (hence the name, C₄), as a result of which, the photorespiration pathway is by-passed, and the wasteful loss of CO₂ (as in C₃ carbon fixation pathway) is minimized.