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Leaves Change Color

Answer Key

Photosynthesis is the process plants use to make food. The food they make is called glucose. To make glucose, plants need sunlight. They also need a chemical called chlorophyll. Chlorophyll gives plants their green color. As autumn approaches and days get shorter, plants get less sunlight. Photosynthesis stops and chlorophyll starts to disappear from the leaves. Now other colors also can be seen. The red and purple colors are caused by glucose that was trapped in the leaves when photosynthesis stopped. The brown colors are caused by waste trapped in the leaves. The orange and yellow colors were always there; they were just hidden by the green color of the chlorophyll.

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