The coral is the Han Viet noun that refers to a class of scientific invertebrates called Anthozoa, the Japanese called Hoa Trung, French called Anthozoaires, called Corals or Sea anemones, Germany called Blumentiere.
Corals exist in the form of small polyps like anemones, often living in populations of many identical individuals. These individuals secrete calcium carbonate to build hard bones, building coral reefs in tropical waters.
Statistics scientists have about 1,200 to 1,300 species of corals worldwide. Half of these species are in coral reefs. The coral belt that we see is the result of about 18,000 years to 20,000 years of construction.
Vietnamese coral has the highest diversity of species in the world. Scientists have investigated that Vietnam has about 1,222 km of coral reefs, distributed throughout the coast from North to South. Most in Central and South. About 400 species have been identified. In Vietnam, up to 90% of hard corals of the Indo-Pacific region.
Coral species grow in shallow waters, warm water, fast flow, high temperature and clean. Most corals can germinate and these sprouts cannot be separated from the mother's body, creating a linked population with a branched tree shape that many people think of corals as plants.
However, the fact that corals are a low-enteral intestinal animal , have two lungs, often use tentacles around their mouths to catch prey. Especially, 80% of the coral's nutritional needs come from photosynthetic activity of the single-celled algae symbiosis with it. At the same time, this activity also contributes to the supply of oxygen to the environment. So in this respect, some people misunderstand that corals are a photosynthetic autotrophic plant.