trichocyst

trich·o·cyst

T0349200 (trĭk′ə-sĭst′)n. An organelle in certain protozoans, especially ciliates, consisting of filamentous fibers that are discharged suddenly.

trich′o·cys′tic adj.

trichocyst

(ˈtrɪkəˌsɪst) n (Zoology) any of various cavities on the surface of some ciliate protozoans, each containing a sensory thread that can be ejected ˌtrichoˈcystic adj

trich•o•cyst

(ˈtrɪk əˌsɪst)

n. a small sac in certain protozoans that contains a hairlike stinger. [1850–55]

Trichocyst

enUK

trichocyst

[′trik·ə‚sist] (invertebrate zoology) A minute structure in the cortex of certain protozoans that releases filamentous or fibrillar threads when discharged.

Trichocyst

a type of extrusome; a cytoplasmic organelle of protozoans that is discharged when the protozoan is mechanically or chemically irritated.

Filamentous trichocysts are protective organelles typical of Infusoria; they are elongated (2–6 microns) albuminous bodies of paracrystalline structure. They generally have a dense tip and are situated in the cytoplasm perpendicular to the surface, as in par-amecia. When discharged, they extend into a filament 20–60 microns long and ending in a sharp point.

There are other types of trichocysts in infusorians, as follows. Mucoid trichocysts, or protrichocysts, are without a sharp point; they swell into a jellylike substance with a houndstooth pattern when discharged. Rhabdocysts are rod-shaped and are completely extruded to the surface of the protozoan. Toxicysts are poisonous organelles of predatory infusorians; they are used for attack and are generally located in a circumoral position. They consist of a long capsule containing a telescoping tubule that extends when discharged. Haptocysts are minute extrusomes located at the tips of antennae; they consist of an ampulla and a short tubule. Cnidocysts, or stinging capsules, are oval or spherical in shape. They contain a wound-up tubular filament that can unwind.

Mastigophorans have mucoid trichocysts, filamentous trichocysts, cnidocysts, and taeniobolocysts. The last is in the form of an albuminous rolled-up ribbon that unrolls when discharged. Cnidosporidians have cnidocysts (polar capsules), which are characteristic of spores. When cnidocysts are discharged, they help attach spores to the host’s body.

I. B. RAIKOV

trichocyst

trich·o·cyst

(trik'ō-sist), One of a number of structures, in the form of minute elongated cysts, arranged radially around the periphery of a protozoan cell and containing fluid that when discharged serves for offense or defense; found in ciliates, such as Paramecium species. Synonym(s): trichite [tricho- + G. kystis, bladder]

trichocyst

(trĭk′ə-sĭst′)n. An organelle in certain protozoans, especially ciliates, consisting of filamentous fibers that are discharged suddenly.

trich′o·cys′tic adj.

trichocyst

(1) Trichilemmal cyst, see there.
(2) An elongated vesicular structure found in ciliate protozoa, which contains toxic substances used for defence.

trichocyst

a thread-like structure of uncertain function found in some PROTOZOANS, which is ejected from a pit on stimulation.

单词	trichocyst
释义	trichocyst enUK trich·o·cyst T0349200 (trĭk′ə-sĭst′)n. An organelle in certain protozoans, especially ciliates, consisting of filamentous fibers that are discharged suddenly. trich′o·cys′tic adj. trichocyst (ˈtrɪkəˌsɪst) n (Zoology) any of various cavities on the surface of some ciliate protozoans, each containing a sensory thread that can be ejected ˌtrichoˈcystic adj trich•o•cyst (ˈtrɪk əˌsɪst) n. a small sac in certain protozoans that contains a hairlike stinger. [1850–55] Trichocyst enUK trichocyst [′trik·ə‚sist] (invertebrate zoology) A minute structure in the cortex of certain protozoans that releases filamentous or fibrillar threads when discharged. Trichocyst a type of extrusome; a cytoplasmic organelle of protozoans that is discharged when the protozoan is mechanically or chemically irritated. Filamentous trichocysts are protective organelles typical of Infusoria; they are elongated (2–6 microns) albuminous bodies of paracrystalline structure. They generally have a dense tip and are situated in the cytoplasm perpendicular to the surface, as in par-amecia. When discharged, they extend into a filament 20–60 microns long and ending in a sharp point. There are other types of trichocysts in infusorians, as follows. Mucoid trichocysts, or protrichocysts, are without a sharp point; they swell into a jellylike substance with a houndstooth pattern when discharged. Rhabdocysts are rod-shaped and are completely extruded to the surface of the protozoan. Toxicysts are poisonous organelles of predatory infusorians; they are used for attack and are generally located in a circumoral position. They consist of a long capsule containing a telescoping tubule that extends when discharged. Haptocysts are minute extrusomes located at the tips of antennae; they consist of an ampulla and a short tubule. Cnidocysts, or stinging capsules, are oval or spherical in shape. They contain a wound-up tubular filament that can unwind. Mastigophorans have mucoid trichocysts, filamentous trichocysts, cnidocysts, and taeniobolocysts. The last is in the form of an albuminous rolled-up ribbon that unrolls when discharged. Cnidosporidians have cnidocysts (polar capsules), which are characteristic of spores. When cnidocysts are discharged, they help attach spores to the host’s body. I. B. RAIKOV trichocyst enUK trich·o·cyst (trik'ō-sist), One of a number of structures, in the form of minute elongated cysts, arranged radially around the periphery of a protozoan cell and containing fluid that when discharged serves for offense or defense; found in ciliates, such as Paramecium species. Synonym(s): trichite [tricho- + G. kystis, bladder] trichocyst (trĭk′ə-sĭst′)n. An organelle in certain protozoans, especially ciliates, consisting of filamentous fibers that are discharged suddenly. trich′o·cys′tic adj. trichocyst (1) Trichilemmal cyst, see there. (2) An elongated vesicular structure found in ciliate protozoa, which contains toxic substances used for defence. trichocyst a thread-like structure of uncertain function found in some PROTOZOANS, which is ejected from a pit on stimulation.
随便看	antinonian controversey antinonian controversy anti-non-identified extractable nuclear antigen antinoos antinous antinovel antinovelist antinovels antinoös antinoüs antinuclear antinuclear a anti-nuclear alliance of western australia antinuclear antibodies antinuclear antibodies test anti-nuclear antibody antinuclear antibody antinuclear antibody (ana) antinuclear antibody profile antinuclear antibody test antinuclear factor antinuclear factor (anf) antinuclearist antinucleon antinucleoside analogue