coccolith

coccolith
—coccolithic, adj.
/kok"euh lith'/, n.
a microscopic calcareous disk or ring making up part of the covering of certain marine plankton and forming much of the content of chalk rocks.
[1865-70; < NL Coccolithus orig. a genus name; see COCCUS, -O-, -LITH]

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      minute calcium carbonate platelet or ring secreted by certain organisms (coccolithophores, classed either as protozoans or algae) and imbedded in their cell membranes. When the organisms die, the coccoliths are deposited (at an estimated 60,000,000,000 per square metres [10 square feet] annually) onto the ocean floor and form, along with organic debris, a gray sediment. Fossil forms of coccoliths date from as far back as the Cambrian Period (542 to 488 million years ago).

      The taxonomy of these organisms is not yet established. Zoologists place them either in the protozoan order Chrysomonadida or in their own order Coccolithophorida; botanists include them in the algal division Chrysophyta because they contain yellow to brown chromatophores.

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Universalium. 2010.

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Look at other dictionaries:

  • Coccolith — Coc co*lith, n. [Gr. ? a grain, seed + lith.] (Biol.) One of a kind of minute, calcareous bodies, probably vegetable, often abundant in deep sea mud. [1913 Webster] …   The Collaborative International Dictionary of English

  • coccolith — [käk′ə lith΄] n. [< ModL coccus (see COCCUS) + LITH] a minute calcareous plate covering the body of certain golden algae (division Chromophycota) …   English World dictionary

  • Coccolith — False colour scanning electron micrograph of Gephyrocapsa oceanica, showing the coccoliths. Coccoliths are individual plates of calcium carbonate formed by coccolithophores (single celled algae such as Emiliania huxleyi) which are arranged around …   Wikipedia

  • Coccolith — REM Aufnahme eines Coccolithen von Discoaster surculus aus dem Paläogen Coccolithen sind mikroskopische (maximal 0,01 mm große) scheibenförmige Plättchen aus Kalk, die die Schale von Kalkalgen der Ordnung Coccolithophorida bilden. Das aus… …   Deutsch Wikipedia

  • coccolith — noun A microscopic skeletal plate of calcite on the surface of certain marine phytoplankton; it forms chalk and limestone when fossilized …   Wiktionary

  • coccolith — tiny calcareous plate whose fossils form chalk and limestone deposits Stones and Rocks …   Phrontistery dictionary

  • coccolith — [ kɒkəlɪθ] noun Biology a minute rounded calcareous platelet, numbers of which form the spherical shells of coccolithophores. Origin C19: from Gk kokkos grain or berry + lithos stone …   English new terms dictionary

  • coccolith — coc·co·lith …   English syllables

  • coccolith — coc•co•lith [[t]ˈkɒk əˌlɪθ[/t]] n. gel mcr a microscopic calcareous disk or ring making up part of the covering of certain marine plankton and forming much of the content of chalk rocks • Etymology: 1865–70; < NL Coccolithus orig. a genus… …   From formal English to slang

  • coccolith — …   Useful english dictionary

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