From Big Medical Encyclopedia

ANIMALS — one of the largest divisions of the organic world. Animal and vegetable organisms (see. Plants ), and also viruses (see) and a phage, being in a close ekol, interrelation, form the uniform biosphere of Earth

. are characterized heterotrophic (sometimes myxotrophic) by way of food; the active mobility provided with specialized bodies or organellas, existence of a nervous system (at metaphytes), absence at cells of a dense cellulose cover typical for plant cells, restriction of growth of an organism with the small temporary periods (at plants growth continues throughout all life of an individual) etc. At the same time, though there is no uniform criterion of distinctions between animal and vegetable organisms, the unity of their origin from primary one-celled forms is proved (see. Life )

. subdivide on one-celled (Monocytozoa) and multicellular (Metazoa). One-celled are the most simply organized., consisting of a cell with one or several kernels and cytoplasms, in a cut numerous organellas are differentiated (see. Protozoa ). For some types one-celled. formation of colonies, i.e. groups, connected with each other, but structurally isolated individuals is characteristic. At the majority of multicellular. the organism is differentiated on set of cells, various on a structure and functions which form fabrics, bodies, systems of bodies. Functions of all bodies are coordinated by nervous and endocrine systems.

World. it is extremely diverse. More than 1,5 million types are known. The largest systematic categories Zh. — types (see. Taxonomic categories ).

All one-celled. combine in the Protozoa type. Metaphytes form a number of types: sponges (Spongia); coelenterates (Coelenterata); flat worms (Plathelminthes); roundworms (Nemathelminthes); annlides (Annelides); worm-shaped, or shchupaltsevy (Tentaculata); arthropod (Arthropoda); mollusks (Mollusca); pogonofor (Pogonophora); erinaceouses (Echinodermata); chordate (Chordata). The last type is divided into several subtypes, the most numerous of which combines the most high-organized cranial, or vertebrata (Vertebrata), and is divided into classes: fishes (Pisces), amphibious (Amphibia), reptiles (Reptilia), birds (Aves) and mammal (Mammalia).

. are consumers (konsument) of the organic matters created by plants. Herbivorous. are konsument of the first order; carnivorous., eating on herbivorous. — konsument of the second order, and carnivorous, eating carnivorous — konsument of the third order. Parasitic belong to konsument of the second or third orders, in particular. The saprophages feeding on corpses or excrement carry out decomposition of organic matters, their gradual mineralization and return to structure of the inorganic nature. They perform functions of bioreducers and play an important role in implementation of cycle of matter in biocenoses (see).

Animals have huge value for the person. Since ancient times domestic animals (see) serve the person, the circle is various trade animals (see), have great value in scientific, in particular medicobiological, researches laboratory animals (see). Many types., being parasites of the person and., are activators or carriers of various diseases (see. Parasitism , Carriers ); with. the big group of infectious diseases of the person is connected (see. Zoonoza ). The population of many countries suffers from poisonous animals (see). Extensive economic damage is caused by wreckers rural and forestry, and also stocks of food and other products (see. Wreckers of grain, grain products , Wreckers of crops , rodents ). To number Zh., capable to do harm to the person, it is necessary to carry many types insects (see), mollusks (see), worms (see), etc., and also the predators causing essential damage to livestock production in some areas. Representatives of many types. can be sources of activators of a number of diseases of the person and

Zh. V of the USSR systematic fight with harmful to Zh. Poleznye and rare is conducted. are protected by the law: established periods of hunting and trade, are created reserves and National parks will be organized. New types of Zh. Razrabatyvayutsya special events for regulation of number are entered into fauna of the USSR. for the purpose of rational use of useful types. and reduction of the damage caused by harmful. (see. Ecology ).

See also Zoology .

Bibliography: Willie K. and Detye V. Biologiya (Biological processes and laws), the lane with English, M., 1974, bibliogr.; A. G. Biogeografiya's ravens (with elements of biology), M., 1963, bibliogr.; Dyuvinyo P. and M. Biosfer's Tang and the place of the person in it (Ecological systems and the biosphere), the lane with fr., M., 1973, bibliogr.; Severtsov S.A. Dynamics of the population and adaptive evolution of animals, M. — L., 1941, bibliogr.; Structure and functional biogeotseno-ticheskaya a role of the animal population of the land, under the editorship of Yu. A. Isakov, M., 1967.

E. I. Korenberg.