Structure of leaves

• 1. carbon dioxide diffuses into the air spaces within the leaf then it diffuses into the cells where photosynthesis happens leads adapted to allow this happen
• 2. The underneath of the leaf is an exchange surface- covered in little holes called stomata which the CO2 diffuse through
• 3. Oxygen( produced in photosynthesis) and water vapour also diffuse out through the stomata
• 4. The size of the stomata is Controlled by guard cells- they close if the stomata if the plant is loosing water faster then gaining. without guard cells the plant would wilt
• 5. The flattened shape of the leaf increased the area of this exchange surface so that it’s more effective
• 6. The walls of the cells inside the leaf form another exchange surface. the air spaces inside the leaf increase the area of this surface so there’s more chance of CO2 getting into the cells
• The water vapour evaporated from the cells inside the leaf. then it escapes by diffusion