Photosynthesis is the process by which plants and a few other organisms make their own energy using the sun, water and carbon dioxide. Organisms that can make energy for themselves are called autotrophs. The plant will make glucose as part of photosynthesis which can be used as energy. As a part of the process oxygen is released as a biproduct into the atmosphere. Photosynthesis happens in a part of the plant cell called the chloroplast. Our cells do not have chloroplasts because we do not perform photosynthesis. Photosynthesis is important because without it we would not have enough oxygen in the atmosphere to survive. Plants and other photosynthetic organisms produce the oxygen we need in order to breathe!