Dicotyledonous Plant

• With plants, gaseous exchange primarily takes place in the leaves. Gases enter of leave the leaf mainly by diffusion through the stomata found in lower epidermis
• The gaseous exchange surface is largely the outer surface of the spongy mesophyll cells . Have large surface area
• Thin cell walls are moist so O2 and CO2 can easily dissolve
• The spongy mesophyll cells have large intracellular spaces that enable the transport of gases. They occur inside the leaf and are therefore protected by the surrounding plant tissue