LPKW+5.4

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=5.4 Rocks from reefs=

Vocabulary

 * coral reef**-a calcite structure built by coral animals in warm waters
 * atoll**-a ring-shaped coral island

Outline

 * Rocks from reefs**
 * Living coral
 * Coral animals are tiny relitives of jellyfish
 * They produce skeletons that form coral reefs
 * How a reef forms
 * Coral animals absorbs calcium and changes it into calcite.
 * When the animals die, they leave calcite behind
 * They pile up forming reefs
 * Limestone deposits from coral reefs
 * Coral reefs may rise above sea levels
 * This forms limestone
 * Limestone is found in mainly the USA