Q. The C₄ plants are photosynthetically more efficient than C₃ plants because
A) They have more chloroplasts
B) The CO₂ compensation point is more
C) CO₂ generated during photorespiration is trapped and recycled through PEP carboxylase
D) The CO₂ efflux is not prevented
Explanation
[Solution from source] C₄ plants use PEP carboxylase in mesophyll cells to capture CO₂ and concentrate it in bundle sheath cells, so RuBisCO works near saturation and photorespiration is minimal; any CO₂ that leaks out can be refixed by PEP carboxylase. Their efficiency comes from this CO₂-concentrating mechanism, not from simply having more chloroplasts, and their CO₂ compensation point is lower, not higher. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.