contractile vacuole

contractile vacuole
Cell Biol.
a membrane-enveloped cellular organelle, found in many microorganisms, that periodically expands, filling with water, and then contracts, expelling its contents to the cell exterior: thought to be important in maintaining hydrostatic equilibrium. See diags. under ameba, paramecium.

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      regulatory organelle, usually spherical, found in freshwater protozoa and lower metazoans, such as sponges and hydras, that collects excess fluid from the protoplasm and periodically empties it into the surrounding medium. It may also excrete nitrogenous wastes. In amoebas (amoeba) it changes position with the animal's movement; in most ciliates it follows a definite path through the cell; in the Euglena and other flagellates it remains stationary. The filling and emptying cycle may last from seconds to a minute, depending on the species.

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Universalium. 2010.

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  • Contractile vacuole — Vacuole Vac u*ole, n. [L. vacuus empty: cf. F. vacuole.] (Biol.) A small air cell, or globular space, in the interior of organic cells, either containing air, or a pellucid watery liquid, or some special chemical secretions of the cell protoplasm …   The Collaborative International Dictionary of English

  • Contractile vacuole — Contractile Con*tract ile, a. [Cf. F. contractile.] tending to contract; having the power or property of contracting, or of shrinking into shorter or smaller dimensions; as, the contractile tissues. [1913 Webster] The heart s contractile force. H …   The Collaborative International Dictionary of English

  • contractile vacuole — n a vacuole in a unicellular organism that contracts regularly to discharge fluid from the body * * * an osmoregulatory organelle of protozoa and sponges that alternately fills with water extracted from the adjacent cytoplasm and then ejects the… …   Medical dictionary

  • contractile vacuole — contractile vacuole. См. сократительная вакуоль. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Contractile vacuole — Protist Paramecium aurelia with contractile vacuoles A contractile vacuole (abbreviation: CV) is a sub cellular structure (organelle) involved in osmoregulation. It is found predominantly in protists and in unicellular algae. It was previously… …   Wikipedia

  • contractile vacuole — (vak u ōl) In protists and some animals, a clear fluid filled cell vacuole that takes up water from within the cell and then contracts, releasing it to the outside through a pore in a cyclical manner. Contractile vacuoles function primarily in… …   Dictionary of microbiology

  • contractile vacuole — noun Date: 1876 a vacuole in a unicellular organism that contracts regularly to discharge fluid from the body …   New Collegiate Dictionary

  • contractile vacuole — A specialized vacuole of eukaryotic cells, especially Protozoa, that fills with water from the cytoplasm and then discharges this externally by the opening of a permanent narrow neck or a transitory pore. Function is probably osmoregulatory …   Dictionary of molecular biology

  • contractile vacuole — noun A vacuole that removes waste or excess water …   Wiktionary

  • contractile vacuole — noun : a vacuole in many unicellular organisms that gradually enlarges and suddenly collapses, dispersing its watery content often in regular pulsations, and that is thought to maintain the normal hydrostatic relation of the organism with its… …   Useful english dictionary

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