What is coral?

Coral is a marine invertebrate of Polypodiaceae in Echinoderm.

Coral is the oldest marine life on earth, which appeared nearly 500 million years ago. Coral is a kind of marine cylindrical coelenterate, which is automatically fixed on the calcareous remains of ancestral corals at the stage of white larvae. Coral is the shell secreted by coral polyps.

Coral is like a branch, so it is often mistaken for a plant. From a biological point of view, coral is an animal, which is formed by countless tiny corals. Coral is a coelenterate. It is very small, often only a few millimeters, with exquisite posture and bright colors. It is distributed in the equator with a temperature higher than 20℃ and its adjacent tropical and subtropical regions. ?

Coral is bright and beautiful, which can be used as an ornament and has high medicinal value.

Extended data:

The main body of coral reefs is composed of corals.

Coral is a coelenterate in the ocean. It preys on tiny plankton in the ocean, absorbs calcium and carbon dioxide in seawater during its growth, and then secretes limestone to become its living shell.

Each coral is only the size of a grain of rice. They live in groups, metabolize, grow and reproduce from generation to generation, and secrete limestone and stick together. These limestones are compacted and petrified to form islands and reefs, which are called coral reefs. ?

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