Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy. This process primarily occurs in the chloroplasts of plant cells, where the pigment chlorophyll captures sunlight. Plants take in carbon dioxide from the air and water from the soil. Using sunlight, they convert these into glucose (a sugar) and oxygen. The overall chemical reaction can be summarized as: carbon dioxide + water + sunlight → glucose + oxygen. Photosynthesis is essential for life on Earth, as it provides oxygen and serves as the foundation of the food chain.