The process of converting sunlight into energy by plants is called photosynthesis. During photosynthesis, plants use chlorophyll to capture sunlight and convert it into chemical energy. They take in carbon dioxide from the atmosphere and water from the soil, producing glucose (a sugar used for energy and growth) and oxygen as a byproduct. This process is essential not only for the survival of the plants themselves but also for the broader ecosystem, as it forms the basis of the food chain and provides oxygen necessary for many living organisms.