Biology is a natural science concerned with the study of life and living organisms. The leaf consist of a broad, flat part called the lamina, which is joined to the rest of the plant by a leaf stalk or petiole. Running through the petiole are vascular bundles, which then form the veins in the leaf. Although a leaf looks thin, it’s made up of several layers of cells. The term leaf refers to the organ that forms the main lateral appendage on the stem of vascular plants. In general, leaves are thin, flat organs responsible for the photosynthesis of the plant. Leaves are typically oriented on a plant to avoid blocking the sunlight of the leaves situated underneath. The main function of a leaf is to carry out photosynthesis, which provides the plant with the food it needs to survive. Plants provide food for all life on the planet.