vorticella

vorticella
/vawr'teuh sel"euh/, n., pl. vorticellae /-sel"ee/, vorticellas.
any ciliated protozoan of the genus Vorticella, having a transparent, bell-shaped body with a retractile stalk.
[1780-90; < NL; see VORTEX, -ELLA]

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 genus of the ciliate protozoan order Peritrichida, a bell-shaped or cylindrical organism with a conspicuous ring of cilia (hairlike processes) on the oral end and a contractile unbranched stalk on the aboral end; cilia usually are not found between the oral and aboral ends. Vorticellas eat bacteria and small protozoans and live in fresh or salt water attached to aquatic plants, surface scum, submerged objects, or aquatic animals. Although vorticellas are often found in clusters, each stalk is fastened independently. The stalk consists of an external sheath that contains a fluid and a spirally arranged contractile thread. When the vorticella is contracted the stalk thread is shortened, and the sheath is coiled like a corkscrew.

      Vorticellas reproduce by longitudinal fission. One of the two daughter cells retains the original stalk; the other grows a temporary wreath of cilia at the aboral end and migrates. Propelled by these cilia, the migrant eventually grows a stalk, attaches to a substrate, and loses its temporary cilia. In conjugation one small special migrant (microconjugant) finds an attached vorticella (macroconjugant) and the two conjugants amalgamate completely, forming one organism in a sexlike union that eventually leads to fission.

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Universalium. 2010.

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Look at other dictionaries:

  • Vorticella — Vor ti*cel la, n.; pl. E. {Vorticellas}, L. {Vorticell[ae]}. [NL., dim. fr. L. vortex. See {Vortex}.] (Zo[ o]l.) Any one of numerous species of ciliated Infusoria belonging to {Vorticella} and many other genera of the family {Vorticellid[ae]}.… …   The Collaborative International Dictionary of English

  • vorticella — [vôrt΄ə sel′ə] n. pl. vorticellae [vôr΄tə sel′ē] [ModL, dim. < L vortex: see VORTEX] any of a genus (Vorticella) of one celled ciliates living in water, with a bell shaped body on a thin, contractile stem serving as a holdfast …   English World dictionary

  • Vorticella — Vorticella, 1) so v.w. Schnellthierchen, vgl. Blumenthierchen 2); 2) so v.w. Encriniten u. Pentacriniten …   Pierer's Universal-Lexikon

  • Vorticella — Vorticella, s. Infusorien …   Meyers Großes Konversations-Lexikon

  • Vorticella — Vo …   Wikipédia en Français

  • Vorticella —   Vorticella …   Wikipedia Español

  • Vorticella — Taxobox | color = khaki name = Vorticella image width = 200px domain = Eukaryota unranked phylum = Alveolata phylum = Ciliophora classis = Oligohymenophorea subclassis = Peritrichia ordo = Sessilida familia = Vorticellidae genus = Vorticella… …   Wikipedia

  • vorticella — vor·ti·cèl·la s.f. TS zool. protozoo del genere Vorticella con corpo a forma di calice peduncolato, provvisto di ciglia disposte in modo da determinare movimenti a vortice | con iniz. maiusc., genere della famiglia dei Vorticellidi {{line}}… …   Dizionario italiano

  • vorticella — noun (plural vorticellae or cellas) Etymology: New Latin, from Latin vortic , vortex Date: 1787 any of a genus (Vorticella) of stalked bell shaped ciliates …   New Collegiate Dictionary

  • vorticella — [ˌvɔ:tɪ sɛlə] noun Zoology a sedentary, single celled aquatic animal with a contractile stalk and a bell shaped body bearing a ring of cilia. [Genus Vorticella.] Origin C18: mod. L., dimin. of L. vortex, vortic eddy …   English new terms dictionary

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