From Encyclopedia Jr, free information reference for Kids
- This article is about the protozoan. For the Australian doom metal band, see Paramaecium.
| Paramecium |
Paramecium aurelia
|
| Scientific classification |
| Kingdom: |
Protista
|
| Phylum: |
Ciliophora
|
| Class: |
Oligohymenophorea
|
| Order: |
Peniculida
|
| Family: |
Parameciidae
|
| Genus: |
Paramecium
Müller, 1773 |
|
Paramecium is a well-known genus of ciliate protozoa, formerly known as slipper animalcules from their slipper shape. They are commonly studied as a representative of the ciliate group. Paramecia are unicellular and slipper-shaped, ranging from 50 to 300 μm in length, depending on species. Simple cilia cover the body, and allow the cell to move with a synchronous motion; and there is a deep oral groove, containing inconspicuous compound oral cilia, as found in other peniculids. Osmoregulation is carried out by a pair of contractile vacuoles, which actively expel water absorbed by osmosis from the surroundings. Paramecia are widespread in freshwater environments, and are especially common in scums. Paramecia are attracted by acidic conditions.
Paramecia have cilia to help them move in the water. There are also cilia around the oral groove that help draw food into it. They usually feed on bacteria and other smaller cells.
[edit] Species
The division into species is still in flux—for instance, P. aurelia has recently been divided into 14 species—but the following are representative:
- P. aurelia Ehrenberg, 1838
- Paramecium bursaria (Ehrenberg) Focker, 1836
- P. calkinsi Woodruff, 1921
- P. caudatum Ehrenberg, 1838
- P. duboscqui Chatton and Brachon, 1933
- P. jenningsi Diller & Earl, 1958
- P. multimicronucleatum Powers & Mitchell, 1910
- P. nephridiatum von Gelei, 1925
- P. polycaryum Woodruff, 1923
- P. putrinum Claparede & Lachmann, 1858
- P. trichium Stokes, 1885
- P. woodruffi Wenrich, 1928
[edit] Paramecium in popular culture
- In a popular computer program, Chip's Challenge, the main character encounters a cartoon paramecium, one of the many monsters that he must overcome.
- In the Homestar Runner universe, the gang was a "bunch o' parameciums" before they were in middle school.
- In the anime One Piece, Wiper of the Shandian Tribe realizes (after attacking him) that Luffy has eaten a Paramecium-type devil's fruit.
- In an episode of Mad About You it is used as a word that is difficult yet possible to use in an everyday conversation, as to discreetly tell another one involved in the conversation that a point of irriation has been reached by the user.
