Returning from vacation, many bring home souvenirs that will remind you of the sandy beach and the warm sea. Often among them you can find corals. They attract attention with their bizarre appearance, and they are specially mined for the manufacture of souvenirs. And what are corals: plants or animals?

coral reef
At first glance, it may seem that corals are plants that grow in coastal areas and in shallow waters in warm seas. But in fact, corals are the skeleton of a colony of living organisms called coral polyps.

Coral polyps belong to the class of marine invertebrates. Many species of coral polyps live at the bottom in large colonies that form coral reefs of extraordinary beauty. The diversity of coral polyps is more than 6,000 species that live mainly in warm waters, although individual specimens also live northern latitudes. Colonies of coral polyps have been found in the North Atlantic, off the coast of Scotland and even in the rather cool White Sea.

The structure of the coral polyp
Coral polyps reproduce by budding and also by sexual reproduction. The resulting larvae swim for some time in the thickness as zooplankton, and then settle to the bottom, where they spend the rest of their lives. Corals feed, as a rule, on plankton, absorbing it along with sea water during the filtration process. But some species are able to absorb small crustaceans or even fish. The skeleton of corals can be not only calcareous, but also consist of protein compounds. And there are corals that are generally devoid of any skeleton.

Brain coral from the order of stony coral polyps

All coral polyps are divided into two subclasses: six-ray (in which there are 6 orders) and eight-ray (in which there are 5 orders). The most numerous order is stony corals, which includes more than 3,000 species. Representatives of this order are most often found among the inhabitants of coral reefs and in souvenir shops. But other units are no less interesting.

Sea anemones - representatives of six-beam corals of the sea anemone order

Members of the Zoantaria

And this coral polyp from the detachment of sea feathers

Corals are often used not only for making souvenirs, but also in jewelry. For this reason, corals are prohibited from exporting from some countries, such as Turkey, Egypt, Thailand. You can export corals if you have a receipt proving their purchase in the store. But in all other cases, frivolous tourists can expect trouble at customs.

CORALS
marine colonial coelenterates, mainly from the class of coral polyps, partly from the class of hydroids (hydrocorals), characterized by the ability to form a powerful - usually calcareous (from calcium carbonate), less often horny - skeleton, which persists after the death of the animal and contributes to the formation of reefs, atolls and islands. The most famous and important from an environmental point of view are the so-called. stony corals, because it is their growth that leads to the formation of coral reefs and islands. They are found almost exclusively in tropical and subtropical waters with a temperature of at least 21 ° C and at a depth of no more than 27 m. The main places of their distribution are the Caribbean Sea (Florida, Bahamas, West Indies) and the Indo-Pacific region, especially the zone to northeast of Australia (Coral Sea).
Polyps. Corals are usually called only the skeleton of the colony, left after the death of many small polyps. As a rule, they occupy cup-shaped depressions visible on its surface. The shape of these polyps is columnar, in most cases with a disk at the top, from which the tentacles rims extend. The polyps are immovably fixed on a skeleton common to the entire colony and are interconnected by a living membrane covering it, and sometimes by tubes penetrating limestone. The skeleton is secreted by the outer epithelium of polyps, and mainly by their base (sole), so living individuals remain on the surface of the coral structure, and all of it grows continuously. The number of polyps involved in its formation is also constantly increasing through their asexual reproduction(budding). Corals also reproduce sexually, producing tiny free-swimming larvae that eventually settle to the bottom and start new colonies. Usually during the day the polyps shrink, and at night they stretch out and straighten their tentacles, with the help of which they catch various small animals. In addition to madrepore corals belonging to the subclass of six-rayed coral polyps, some other groups of them also deserve attention. so-called. stinging coral from the hydroid class forms dense tangles of calcareous branches pierced by miniature pores. Red or noble coral (Corallium), organ coral (Tubipora) and bright blue sun coral (Heliopora) belong to the subclass of eight-pointed corals and differ from madrepore corals in the presence of eight feathery tentacles in the polyp, and not a multiple of six of their number.

Collier Encyclopedia. - Open Society. 2000 .

See what "CORALS" are in other dictionaries:

corals- Corals. CORALS, marine, predominantly colonial coelenterates. Most have a calcareous skeleton. In tropical seas form coral reefs, atolls; some are brightly colored (usually all shades of yellow, red and brown... ... Illustrated Encyclopedic Dictionary

corals- marine invertebrates of the class of coral polyps such as coelenterates. Some of them have a massive calcareous skeleton. Corals form large colonies, creating atolls, coral reefs and islands. Particularly numerous... Marine Biographical Dictionary

Corals, bright red, pink or white calcareous deposits of marine polyps. Used for making jewelry: 1) Heb. the word peninim, usually translated as pearls and only in Lamentations 4:7 as corals, probably means ... ... Brockhaus Bible Encyclopedia

- (Greek koralion, from koreo I decorate, and hals the sea). A genus of polyps that, attaching one to another, form branches; as they die. They harden, and over time increase, forming whole trees. They come in red, pink and... Dictionary foreign words Russian language

- (Greek singular h. korallion) marine cnidarians, mainly from the class of coral polyps. Corals are also called the skeletons of some types of corals, from which jewelry and various crafts are made ... Big Encyclopedic Dictionary

Mor. cnidarians, ch. arr. from the class of coral polyps, partly from the class of hydroids (neg. hydrocorals). Most K. forms a calcareous (rarely horny) skeleton of various shapes. Thickets of madrepore corals form the basis of coral ... ... Biological encyclopedic dictionary

Fossils. Representatives of the class K. are already known from very ancient Silurian deposits and are found in more or less significant quantities in the sediments of all systems up to the Quaternary, inclusive, and in places among marine sediments they form ... ... Encyclopedia of Brockhaus and Efron

CORALS- (from Greek korallion), 1) marine intestinal animals (coral polyps, hydroid polyps). Most corals form a calcareous, less often horny skeleton of various shapes. Thickets of madrepore corals form the basis of coral ... ... Ecological dictionary

corals- represent the calcareous skeleton of marine polyps and are usually used to make jewelry. The most important of the washbasins for industrial use are mother-of-pearl...

If you had a chance to dive into the depths of the sea, then you probably saw bright corals of bizarre shapes there. They look like living beautiful bushes with numerous branches that you will not find in an ordinary garden.

Are corals an animal or a plant? This thought comes first when faced with this maritime miracle. For a long time, scientists could not figure out what kind of organisms corals belong to. Only in 1982 did a French researcher prove that these were not marine plants.

coral base

They are made up of very small organisms called polyps. This is a class of intestinal invertebrates that can live both in colonies and alone. To date, there are approximately 6,000 species.

These multicellular organisms have appeared since the ancient mammoths. They have only one cavity - the intestines, through which food is digested. Hence their name follows - intestinal. Therefore, there is no dispute about whether corals are an animal or a plant. Polyps can have different sizes - from a millimeter to several centimeters.

There are also huge ones - from half a meter in diameter. These include representatives of the madrepore species. From numerous polyps, one large organism emerges, which resembles a huge bush that attracts the eyes of divers.

The structure of the polyp and nutrition

It is quite primitive and resembles a cylinder with tentacles. Some polyps have a skeleton that is made up of calcium. Not all polyps can move along the seabed. Only their tentacles bend, helping to get food. How does this happen? Coral tentacles pull small fish and shrimp into their nets.

In the intestinal cavity, the polyp has cilia that create a water flow. Thanks to him, oxygen and food enter the body. We hope we have answered the question of whether corals are an animal or a plant.

Dimensions and shape

The rich variety of a wonderful living organism knows no limit. The smallest coral reefs can be a few centimeters long, the largest reach over 5 meters in height! Their shape can be very diverse: in the form of a twig, a curved hook, a barrel, a feather, or even in the form of a household item.

There are also more complex corals, resembling a fan, a bird, an animal. Some colonies grow up, others in breadth. They often look like spread out colorful carpets. What are corals? Their colors are the most diverse - these are shades of red, black, pink, green tones. Blue and purple corals are quite rare.

Features of coral polyps are such that they are found only in tropical and subtropical waters. Some species live in the polar seas in the north. For example, hersemia. Another noteworthy thing is that all corals live mainly in salty clear waters.

Many coral species prefer to live at shallow depths that are well illuminated by daylight. This is due to the fact that this living organism lives in partnership with algae, which need light for photosynthesis. What types of corals are there? The most famous are porous, mushroom-shaped, black. There are about 400 species of corals in the Great Barrier Reef alone!

deep polyps

These include curved corals called "batipates". They can be found at a depth of over 8000 meters! Colonies appear only at the bottom of a solid substance. Also excellent habitats for them are sunken ships, aircraft, underwater structures.

Deep sea corals prefer a sedentary lifestyle. Some of them can move along the seabed, but very slowly. Despite the fact that the structure of corals is primitive, they have complex biological rhythms.

Most often, this unusual organism behaves actively at night. Corals throw out their tentacles like nets and wait for food. As dawn breaks, the polyps shrink and prefer to be at rest.

coral breeding

Scientists believe that this marine organism can reproduce both vegetatively and sexually. Amazing ability, isn't it? Vegetative consists in fragmentation, and then separation of the "child" from the parent polyp.

Usually, a small “plate” is formed on the coral’s stem, which then detaches and takes root on the bottom of the sea soil. The sexual method suggests that the corals must be male and female. This is not the case for all polyps. Reproduction in this case occurs as follows: during fertilization, sperm enter the gastric cavity. Then they go outside and find themselves in the area of ​​\u200b\u200bthe mouth of the female polyp.

Cell division occurs traditionally. As a result of embryonic development, small larvae are formed, which then swim freely in the water. Such information should dispel the doubts of those people who have not yet found a clear answer to the question of whether corals are an animal or a plant.

A little about the benefits

Corals delight the eye with their unusual appearance, but this is not their only advantage. In fact, they are the builders of the marine ecosystem. And they organize it without too much fuss. Forming colonies, they provide a roof over their heads to various marine inhabitants, such as: eels, rays, starfish and various fish.

Jewelers claim that marine polyps are an excellent material for the manufacture of various products. It is known that in ancient times, coral necklaces were hung around the neck of small children for better growth teeth. It was also believed that sea gifts help in difficult situations. Therefore, they were used as an amulet that could protect from the evil eye and give strength in difficult situations. traditional healers believe that corals regulate metabolism, have a beneficial effect on cardiovascular system improve memory.

In conclusion, I would like to note that corals belong to the animal world and you can tell a lot of interesting things about them.

Coral

coral jewelry

Coral is the skeletal material of the colony coral polyps. Large accumulations of coral form coral reefs and coral islands. The “growth” of corals is usually, even under favorable conditions, no more than 1 cm per year in the longitudinal direction, so it can take centuries to form an average reef, and millennia for islands.

Etymology

The Russian word "coral" ascends through it. Koralle or Polish. coral to lat. corallium, which, in turn, was borrowed from other Greek. κοράλλιον . Modern names of corals in oriental languages: Persian "bussad", Armenian "boost", Arabic "mariam" and so on.

Chemical composition and properties

Application

In nature, more than 3,500 varieties of corals are known, in the palette of which up to 350 color shades are distinguished. Corals are used as a raw material for lime production, some species are used for making jewelry. In the latter case, black (akkabar), white and silver-pearl “angel skin”, and the most popular red and pink precious corals are especially valued.

Pink, red and black corals are considered the most valuable.

Links

Notes

Literature

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Synonyms:

See what "Coral" is in other dictionaries:

Coral- (Nikolaev, Ukraine) Hotel category: Address: Admiral Makarov Street 22, Nikolaev, 54030, Ukraine … Hotel catalog

Greek koralion, from koreo, decorate, and hals, sea. A genus of polyps, which, when combined, form branches, little by little filled with stony substance; over time, the branches increase and the whole mass represents the appearance of a tree. Above… … Dictionary of foreign words of the Russian language

Polyp Dictionary of Russian synonyms. coral n., number of synonyms: 30 agaricia (1) acori ... Synonym dictionary

coral- An animal belonging to the type of cnidarians; has a modified generational change with a predominance of the attached polyp form. Being a predator, the coral captures the prey with the help of stinging cells. )