Photosynthesis is a process by which plants produce energy for its survival. It follows a very simple chemical reaction:carbon dioxide + water (+sunlight) => glucose (energy) + oxygen. Carbon dioxide comes from the air and goes through the stomata of a plant on the underside of the leaf. The water comes from the soil and is absorbed via the root hair cells at the bottom of the plant. The water is transported to the leaf through the xylem. Sunlight is absorbed by the chloroplasts in the plant cells on the leaves. The chemical reaction using carbon dioxide, water and sunlight produce glucose (which the cell will use for energy) and oxygen. The oxygen is released into the air through the stomata.