Untitled Document Photosynthesis Leaves are like small factories that produce food for the plant. Different parts of the leaf have different jobs. The veins in a leaf are bundles of tiny tubes that carry water and minerals to the leaf and return food from the leaf to the rest of the plant.
Veins also help to support the leaf.
On the underside of the leaf are small openings or pores called the stomata. The stomata serve as the lungs of the leaf allowing air to enter. The stomata allow the evaporation of water and the release of oxygen during the night. The outer layers of the leaf are covered with a waxy layer which prevents the leaf from drying out. Leaves are green because they contain small bodies in the cells called chloroplasts.