Photosynthesis

This passage describes the plant process called photosynthesis.

Lexile Level: 490L

Categories: Science & Technology Animals & Nature

Photosynthesis is a process that helps trees make energy. Trees need energy to grow. The process is like a recipe. It turns light, water, and carbon dioxide into sugar. In winter, there isn't enough light for this process. Trees can't make enough sugar to stay healthy. They need to save energy. As a result, trees "go to sleep." In other words, the process stops. As days get shorter in the fall, trees stop making chlorophyll. Chlorophyll helps trees collect light. Remember, light is part of the recipe. Without chlorophyll, photosynthesis doesn't work. You can see when a tree stops making chlorophyll. You can see trees prepare for winter. Chlorophyll gives trees their green color. When trees stop making chlorophyll, they lose their green color. It fades away. Leaves turn red, orange, yellow, and brown. Surprisingly, trees always have these colors. They are just hidden by the green color.