Question

Coral reefs is diverse underwater
ecosystems hold together by calcium
carbonate structures. They were
secreted by corals. Colonies of animals built
coral reefs. These animals is found in marine water
An individual coral is knew as a polyp.
It are a very small and simple organism
Coral reefs looks beautiful
and is admired
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Answer 1

Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and jellyfish.

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