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Ocean and Ocean Basins
More than half of Earth’s surface is
ocean. Water in the ocean is cold in the
far north and far south, and warm in the
middle parts of the planet. The warm
ocean basins are called tropical oceans.
Life on land is based on plants. But there are few plants in the
tropical oceans. The tropical oceans are known for the diversity of
their animals. The most important animals in tropical oceans are the
corals. They surround themselves with hard shells for protection. In
this way, they build huge structures called reefs. Thousands of animals
make their homes in the coral-reef environment.
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