Question

RuBisco is an enzyme that acts both as a carboxylase and oxygenase. Why do you think RuBisco carries out more carboxylationin in C₄ plants.

Answer 1

1. The C₄ plants have dimorophic chloroplasts. In mesophyll cells chloroplast are granal but in bundle sheath cells the chloroplasts are agranal.

2. So in the these plants when CO₂ is fixed in bundle sheath cells, the intracellular CO₂ concentration is increased that is why RuBisco enzyme carries out more carboxylation in C₄ plants.