Plants are made up of organs, including roots, leaves, the stem and reproductive organs. Each organ has its own functions, e.g. Roots keep a plant in the ground. They also absorb water and nutrients from the soil. Leaves absorb sunlight, and make food for the plant by photosynthesis. The waste product of photosynthesis, oxygen, escapes through tiny holes in the leaves. The stem supports the leaves and flowers. It also transports water and nutrients between the roots and the leaves. Reproductive organs allow a plant to produce new plants.