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epidermis
epidermis
1. (in zoology) The outermost layer of cells of the body of an animal. In invertebrates the epidermis is normally only one cell thick and is covered by an impermeable cuticle. In vertebrates the epidermis is the thinner of the two layers of skin (compare dermis). It consists of a basal layer of actively dividing cells (see Malpighian layer), covered by layers of cells that become impregnated with keratin (see keratinization). The outermost layers of epidermal cells (the stratum corneum) form a water-resistant protective layer. The epidermis may bear a variety of specialized structures (e.g. feathers, hairs). 2. (in botany) The outermost layer of cells covering a plant. It is overlaid by a cuticle and its functions are principally to protect the plant from injury and to reduce water loss. Some epidermal cells are modified to form guard cells (see stoma) or hairs of various types (see piliferous layer). In woody plants the functions of the shoot epidermis are taken over by the periderm tissues (see cork cambium) and in mature roots the epidermis is sloughed off and replaced by the hypodermis. |
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"epidermis." A Dictionary of Biology. 2004. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." A Dictionary of Biology. 2004. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O6-epidermis.html "epidermis." A Dictionary of Biology. 2004. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-epidermis.html |
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epidermis
ep·i·der·mis / ˌepiˈdərmis/ • n. Biol. the outer layer of cells covering an organism, in particular: ∎ Zool. & Anat. the surface epithelium of the skin of an animal, overlying the dermis. ∎ Bot. the outer layer of tissue in a plant, except where it is replaced by periderm. DERIVATIVES: ep·i·der·mal / -ˈdərməl/ adj. ep·i·der·mic adj. ep·i·der·moid adj. |
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"epidermis." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O999-epidermis.html "epidermis." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-epidermis.html |
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epidermis
epidermis In animals, outer layer that contains no blood vessels. In many invertebrates, it is only one cell thick. In vertebrates, it may comprise several layers and forms part of the skin. In plants, the epidermis is the outermost layer of a leaf or of an unthickened stem or root; it is usually coated in a waxy layer, the cuticle, which reduces water loss.
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"epidermis." World Encyclopedia. 2005. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." World Encyclopedia. 2005. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O142-epidermis.html "epidermis." World Encyclopedia. 2005. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-epidermis.html |
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epidermis
epidermis (epi-der-mis) n. the outer layer of the skin, which is divided into four layers (see illustration overleaf). The top three layers are continually renewed as cells from the continuously dividing Malpighian layer are gradually pushed outwards and become progressively impregnated with keratin (see keratinization).
—epidermal adj. |
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"epidermis." A Dictionary of Nursing. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." A Dictionary of Nursing. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O62-epidermis.html "epidermis." A Dictionary of Nursing. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-epidermis.html |
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epidermis
epidermis The outermost layer or layers of cells in an animal. It is one cell thick in many invertebrates, but many cells thick in vertebrates. In land-dwelling vertebrates its surface layer is formed from dead, hardened (keratinized) cells. See also INTEGUMENT.
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MICHAEL ALLABY. "epidermis." A Dictionary of Zoology. 1999. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "epidermis." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O8-epidermis.html MICHAEL ALLABY. "epidermis." A Dictionary of Zoology. 1999. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-epidermis.html |
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epidermis
epidermis The outermost layer or layers of cells in a plant or animal. It is one cell thick in plants.
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MICHAEL ALLABY. "epidermis." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "epidermis." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O7-epidermis.html MICHAEL ALLABY. "epidermis." A Dictionary of Plant Sciences. 1998. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-epidermis.html |
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epidermis
epidermis XVII. — late L. — Gr. epidermís, f. EPI- +dérma skin.
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T. F. HOAD. "epidermis." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "epidermis." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O27-epidermis.html T. F. HOAD. "epidermis." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-epidermis.html |
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epidermis
epidermis see skin . |
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"epidermis." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1E1-X-epidermi.html "epidermis." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-epidermi.html |
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epidermis
epidermis
•Alice, chalice, challis, malice, palace, Tallis
•aurora australis
•Ellis, trellis
•necklace
•aurora borealis, Baylis, digitalis, Fidelis, rayless
•ageless • aimless • keyless
•amaryllis, cilice, Dilys, fillis, Phyllis
•ribless • lidless • rimless
•kinless, sinless, winless
•lipless • witless • annus mirabilis
•annus horribilis • syphilis
•eyeless, skyless, tieless
•polis, solace, Wallace
•joyless
•Dulles, portcullis
•accomplice
•Annapolis, Indianapolis, Minneapolis
•Persepolis
•acropolis, cosmopolis, Heliopolis, megalopolis, metropolis, necropolis
•chrysalis • surplice • amice • premise
•airmiss • Amis • in extremis • Artemis
•promise
•pomace, pumice
•Salamis
•dermis, epidermis, kermis
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"epidermis." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "epidermis." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O233-epidermis.html "epidermis." Oxford Dictionary of Rhymes. 2007. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-epidermis.html |
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