Columnar

Columnar

In biology, columnar refers to the shape of epithelial cells that are taller than they are wide.[1] Form follows function in biology, and columnar morphorphology hints at the functions of the cell. Columnar cells are important in absorption and movement of mucus. The cells may or may not bear microvilli (involved in maximizing the surface area for intestinal absorption) or cilia (involved in moving mucus and trapped material up the respiratory passages to be expectorated or swallowed). Columnar epithelium may be simple or stratified. Simple columnar epithelium is most common and involves one layer of cells attached to a basement membrane. The nucleus is closer to the basal aspect of the cell than the apical aspect. Single stratification tends to indicate absorptive function. Stratified columnar epithelium is rare but can be found in salivary glands. It consists of a layer of columnar epithelium resting on top of at least one other layer of epithelial cells, which may have any shape (columnar, cuboidal, or squamous). Stratification in cuboidal tissue has a secretory function.

References

  1. ^ Microanatomy Web Atlas

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  • Columnar — Co*lum nar, a. [L. columnaris, fr. columna.] Formed in columns; having the form of a column or columns; like the shaft of a column. [1913 Webster] {Columnar epithelium} (Anat.), epithelium in which the cells are prismatic in form, and set upright …   The Collaborative International Dictionary of English

  • columnar — columnár adj. m., pl. columnári; f. sg. columnáră, pl. columnáre Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic  COLUMNÁR, Ă adj. (Despre structura rocilor) În formă de columnă; asemănător unei columne. [< …   Dicționar Român

  • columnar — 1728, from L.L. columnaris rising in the form of a pillar, from columna column (see COLUMN (Cf. column)) …   Etymology dictionary

  • columnar — columnarity /kol euhm nar i tee/, n. /keuh lum neuhr/, adj. 1. shaped like a column. 2. characterized by columns: columnar architecture. 3. Also, columnal. printed, arranged, etc., in columns: data in columnar form. [1720 30; < LL columnaris,… …   Universalium

  • columnar — co·lum·nar kə ləm nər adj of, relating to, being, or composed of tall narrow somewhat cylindrical or prismatic epithelial cells <columnar epithelium> <columnar tissue> …   Medical dictionary

  • columnar — adjective 1. having the form of a column trees with columniform trunks columnar forms a columnlike tree trunk • Syn: ↑columniform, ↑columnlike • Similar to: ↑columned …   Useful english dictionary

  • columnar — column ► NOUN 1) an upright pillar supporting an arch or other structure or standing alone as a monument. 2) a line of people or vehicles moving in the same direction. 3) a vertical division of a page or text. 4) a regular section of a newspaper… …   English terms dictionary

  • Columnar epithelial cell — Code TH H2.00.02.0.01012 Columnar epithelia are epithelial cells whose heights are at least four times their width. Columnar epithelia are divided into simple (or unilayered), and stratified (or multi layered). Simple columnar epithelia… …   Wikipedia

  • Columnar epithelia — are epithelial cells whose heights are at least four times their width. Columnar epithelia are divided into simple (or unilayered), and stratified (or multi layered). * Simple columnar epithelia * Stratified columnar epithelia * Pseudostratified… …   Wikipedia

  • Columnar epithelium — Columnar Co*lum nar, a. [L. columnaris, fr. columna.] Formed in columns; having the form of a column or columns; like the shaft of a column. [1913 Webster] {Columnar epithelium} (Anat.), epithelium in which the cells are prismatic in form, and… …   The Collaborative International Dictionary of English

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