The process by which plants convert sunlight into energy is called photosynthesis. During photosynthesis, plants utilize sunlight, carbon dioxide from the air, and water from the soil to produce glucose, which serves as their energy source. In this process, chlorophyll, the green pigment in plant leaves, captures sunlight and initiates a series of chemical reactions. Oxygen is released as a byproduct of photosynthesis, contributing to the Earth's atmosphere. This process is fundamental not only for plant life but also for the entire ecosystem, as it forms the basis of the food chain and provides oxygen for other living organisms.