cilium(redirected from Cirrus (organ))
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singular of cilia.
cil·i·a(sil'ē-ŭm, -ă), Do not confuse this word with psyllium.
1. Synonym(s): eyelash
2. A motile extension of a cell surface, for example, of certain epithelial cells, containing nine longitudinal double microtubules arranged in a peripheral ring, together with a central pair.
[L. an eyelid]
cilium/cil·i·um/ (sil´e-um) [L.] singular of cilia.
n. pl. cil·ia (-ē-ə)
1. A microscopic hairlike process extending from the surface of a cell or unicellular organism. Capable of rhythmical motion, it acts in unison with other such structures to bring about the movement of the cell or of the surrounding medium.
2. An eyelash.
3. Botany One of the hairs along the margin or edge of a structure, such as a leaf, usually forming a fringe.
cil·i·um, pl. cilia (sil'ē-ŭm, -ă)
1. Synonym(s): eyelash.
2. A motile extension of a cell surface, e.g., of certain epithelial cells, containing nine longitudinal double microtubules arranged in a peripheral ring, together with a central pair.
[L. an eyelid]
cilium(pl. cilia) a fine cytoplasmic structure in the form of a thread which projects from the surface of cells. Each cell may bear numerous cilia which beat constantly in one direction, either moving liquid over the surface of the cells concerned or moving the cell(s) in relation to the liquid, for example, locomotion in PROTOZOANS. They are also present in all Metazoa except the ARTHROPODS and NEMATODES, but in only a few plants, for example, cycads. The cilium has a similar structure to the FLAGELLUM, consisting of an outer membrane surrounding a matrix containing two central MICROTUBULES around which is a ring of nine more microtubules (a ‘9 + 2’ structure). At the base of the cilium is a basal body concerned with ATP production.
ciliummotile extensions of some cell types (e.g. ciliated epithelium)
An eyelash (plural: cilia).
pl. cilia [L.] see cilia.