Question

The C4 plants are photosynthetically more efficient than C3 plants because

• A. They have more chloroplasts
• B. The carbon dioxide compensation point is more
• C. Carbon dioxide generated during photorespiration is trapped and recycled through PEP carboxylase
• D. The carbon dioxide efflux is not prevented

Answer 1

The correct option is C Carbon dioxide generated during photorespiration is trapped and recycled through PEP carboxylase

C4 plants use PEP carboxylase to capture more carbon dioxide in the mesophyll cells and shuttled it to bundle-sheath cells as malate. In these bundle-sheath cells carbon dioxide is released by decarboxylation of the malate.
Therefore, C4 plants are more efficient at fixing carbon dioxide than C3 plants.