Both C₃ and C₄ plants have the enzymes of the Calvin cycle.How are C₄ plants more efficient than C₃ plants at fixing carbon?
A)In C₄ plants,carbon fixation takes place in mesophyll cells,whereas the Calvin cycle takes place in bundle-sheath cells.
B)Both the carbon fixation reaction and the Calvin cycle take place in mesophyll cells,but the carbon fixation reactions take place in the dark,and the Calvin cycle is light dependent.
C)C₄ plants do not have rubisco and therefore do not undergo photorespiration.
D)C₄ plants fix carbon using the Calvin cycle;C₃ plants use the reverse of glycolysis,a series of reactions that requires more energy in the form of ATP.

Question

Quizplus · Accepted Answer

C₄ plants are more efficient at fixing carbon due to their unique anatomy and physiology. In C₄ plants, carbon fixation occurs in mesophyll cells, which are close to the leaf surface and have a high concentration of CO₂. The fixed carbon is then transported to bundle-sheath cells, where the Calvin cycle takes place. This separation of carbon fixation and the Calvin cycle reduces photorespiration and allows for a more efficient use of CO₂. C₃ plants, on the other hand, fix carbon and carry out the Calvin cycle in the same cells, resulting in more photorespiration and less efficient carbon fixation.

Both C₃ and C₄ Plants Have the Enzymes of the Calvin