This is the process of photosynthesis. Photosynthesis is the process by which green plants make their own food, it occurs in two stages; the light dependent stage and the light independent stage (dark stage). During the first stage energy from the sunlight is used to break water molecules to yield oxygen atoms and hydrogen ions. Then in the dark stage involves the fixation of carbon dioxide to yield simple sugars. Therefore, the end products are organic compounds and oxygen gas.