What is the characteristic of C3 Plants versus C4 Plants?
How they gather CO2 and their leaf structure
C3 plants use the CO2 directly in the calvin cycle. These plants are usually found in places where water supply is no problem, as a lot of water can evaporate in these plants.
C4 plants fix their CO2 in the cytoplasm of the mesophyll cells first. In these cell the CO2 is bound to PEP, which is then transported into the bundle sheath cell to be used in the calvin cycle