Cam stands for Crassulacean acid metabolism.

C3 and C4 conserve less water than Cam plants.

Actually, C4 plant captures more carbon than C3 plant. In the struggle to reduce carbon dioxide concentration in the atmosphere, genetic scientists have modified some large-scale crops into C4 bases. Cam plant is wholly different from C3 and C4 and examples of are the cactus and other succulent plants in order to survive in dry dusty regions. In Cam plants, carbon fixation occurs at night while C3 and C4 plants carry out photosynthesis during daylights.