The process that plants undergo to produce oxygen is called photosynthesis. During photosynthesis, plants use sunlight, water, and carbon dioxide to create glucose and oxygen. This process occurs primarily in the chloroplasts of plant cells, where chlorophyll captures sunlight. The overall chemical reaction can be summarized as: 6CO2 + 6H2O + light energy → C6H12O6 + 6O2. In this reaction, carbon dioxide and water are converted into glucose (a form of energy storage for the plant) and oxygen, which is released into the atmosphere. Photosynthesis is essential for life on Earth, as it is the basis of the food chain and produces the oxygen we breathe.