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The green leaves of plants make food from carbon dioxide and water.

The Moon has no natural life because it has no air or water.

Sun

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carbon dioxide from air

water from roots

in carbon dioxide from the atmosphere, and water from the ground. The two substances combine in a chemical reaction in the plants’ leaves to make their food, sugar. But this process takes place only in the daytime because it needs the energy in sunlight to make it work. That is why it is called photosynthesis , which means making with light.

leaf gives out oxygen

Light work Besides warmth, water and oxygen, living things also need food. Both animals and plants need to consume food to produce energy. They need energy to make their bodies work and for growth and, in the case of animals, movement. Animals eat plants or other animals. They cannot make their own food. Plants can make their own food from carbon dioxide gas and water. They take

∆ Sunscreen can protect skin from invisible ultraviolet rays.

Alligators in one of Florida’s swamps raise their body temperature by basking in the Sun.

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