Video narration
Photosynthesis is how plants make their own food. Instead of eating, a plant uses sunlight as energy to build sugar, which it uses to grow and stay alive. Here’s the simple recipe: the plant takes in carbon dioxide from the air through tiny openings in its leaves, and it pulls water up from the soil through its roots. In the leaves, sunlight powers a chemical change that combines that carbon dioxide and water into sugar. As a helpful bonus, the plant releases oxygen back into the air. So the main inputs are light, water, and carbon dioxide, and the main outputs are sugar for the plant and oxygen for us. That’s why photosynthesis matters: it fuels plant life and helps keep the air breathable.