Flagellate

Flagellate
"Flagellata" from Encyclopædia Britannica
"Flagellata" from Ernst Haeckel's Artforms of Nature, 1904
Parasitic excavate (Giardia lamblia)
Green alga (Chlamydomonas)

Flagellates are organisms with one or more whip-like organelles called flagella. Some cells in animals may be flagellate, for instance the spermatozoa of most phyla. Flowering plants do not produce flagellate cells, but ferns, mosses, green algae, some gymnosperms and other closely related plants do. Likewise, most fungi do not produce cells with flagellae, but the primitive fungal chytrids do. Many protists take the form of single-celled flagellates.

The word flagellate describe a particular construction of eukaryotic organism and its means of motion. The term does not imply any specific relationship or classification of the organisms that possess flagellae. However, the term "flagellate" is included in other terms (such as "dinoflagellate" and "zooflagellate") which often are more formally characterized.[1]

Form and behavior

Eukaryotic flagella are supported by microtubules in a characteristic arrangement, with nine fused pairs surrounding two central singlets. These arise from a basal body or kinetosome, with microtubule roots that are an important part of the cell's brain. In some, for instance, they support a cytostome or mouth, where food is ingested. The flagella often supports hairs, called mastigonemes, or contain rods. Their ultrastructure plays an important role in classifying eukaryotes.

In protoctists and microscopic animals, flagella are generally used for propulsion. They may also be used to create a current that brings in food. In most things, one or more flagella are located at or near the anterior of the cell e.g. Euglena. Often there is one directed forwards and one trailing behind. Among animals, fungi, and Choanozoa, which make up a group called the opisthokonts, there is a single posterior flagellum. They are from the phylum Mastigophora. They can cause diseases and they can make their own food. They reproduce by binary fission.

References

  1. ^ Cavalier-Smith T (1995). "Zooflagellate phylogeny and classification". Tsitologiia 37 (11): 1010–29. PMID 8868448. 

External links


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  • flagellate — Ⅰ. flagellate [1] ► VERB ▪ flog, either as a religious discipline or for sexual gratification. DERIVATIVES flagellation noun. ORIGIN Latin flagellare whip . Ⅱ. flagellate [2] …   English terms dictionary

  • flagellate — [flaj′ə lāt΄; ] for adj., also [ flaj′ə lit ] or [ flə jel′it] vt. flagellated, flagellating [< L flagellatus, pp. of flagellare, to whip, scourge < flagellum, a whip, dim. of flagrum < IE base * bhlaĝ , to beat > ON bluk, a slap] to… …   English World dictionary

  • Flagellate — Flag el*late, v. t. [imp. & p. p. {Flagellated}; p. pr. & vb. n. {Flagellating}.] [L. flagellatus, p. p. of flagellare to scoure, fr. flagellum whip, dim. of flagrum whip, scoure; cf. fligere to strike. Cf. {Flall}.] To whip; to scourge; to flog …   The Collaborative International Dictionary of English

  • Flagellate — Fla*gel late, a. 1. Flagelliform. [1913 Webster] 2. (Zo[ o]l.) Of or pertaining to the Flagellata. [1913 Webster] 3. Having a flagellum or flagella. [PJC] …   The Collaborative International Dictionary of English

  • flagellate — index beat (strike), ill use, lash (strike) Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • flagellate — (v.) 1620s, from L. flagellatus, pp. of flagellare to scourge, lash (see FLAGELLUM (Cf. flagellum)). Related: Flagellated; flagellating. An earlier verb for this was flagellen (mid 15c.) …   Etymology dictionary

  • flagellate — [v] whip, lash beat, beat the living daylights out of*, belt, flay, flog, hit, lash, spank, tan*, tan someone’s hide*, thrash; concept 189 …   New thesaurus

  • flagellate — I. transitive verb ( lated; lating) Etymology: Latin flagellatus, past participle of flagellare, from flagellum, diminutive of flagrum whip; perhaps akin to Old Norse blaka to wave Date: circa 1623 1. whip, scourge 2. to drive or punish as if by… …   New Collegiate Dictionary

  • flagellate — 1. Possessing one or more flagella. 2. Common name for a member of the class Mastigophora. collared f. SYN: choanomastigote. * * * fla·gel·late flaj ə lət, .lāt; flə jel ət adj 1 a) or flag·el·lat·ed …   Medical dictionary

  • flagellate protozoan — noun a usually nonphotosynthetic free living protozoan with whiplike appendages; some are pathogens of humans and other animals • Syn: ↑flagellate, ↑flagellated protozoan, ↑mastigophoran, ↑mastigophore • Derivationally related forms: ↑flagellate… …   Useful english dictionary

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