Biology AQA Leaf structure and adaptations of a leaf 1. Label the section through a leaf 2. Draw arrows to show how light enters and the passage of CO2 and O2 3. Complete the table below to give the name of each part Name of part Function Tiny pores on the underside of the leaf, where gasses diffuse in and out. Water vapour is also lost from here. Transports water and mineral ions Layer of cells with air-spaces between them. Gas exchange occurs here. Transparent layer on the top of the leaf. Waxy layer at the top of the leaf Layer of long cylindrical cells where most photosynthesis happens Control the closing and opening of the stomata Single layer of flat cells covering the bottom surface of the leaf. Transports dissolved sugars in the plant 4. Extension questions in your green book: Why is the leaf an organ? Give three adaptations of the leaf for photosynthesis.