metamerism

metamerism
1. A type of anatomic structure exhibiting serially homologous metameres; in primitive forms, such as the annelids, the metameres are almost alike in structure; in vertebrates, specialization in the cephalic region masks the underlying m., which is still clearly evident in serially repeated vertebrae, ribs, intercostal muscles, and spinal nerves, and in young vertebrate embryos. 2. In chemistry, rarely used synonym for structural isomerism.

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me·tam·er·ism mə-'tam-ə-.riz-əm n
1) isomerism esp. of chemical compounds of the same type
2) the condition of having or the stage of evolutionary development characterized by a body made up of metamers that is usu. held to be an essential prelude to the differentiation of the more highly organized animals (as arthropods and vertebrates) through the disproportionate development and elaboration of some segments together with the coalescence, reduction, or loss of others
3) the phenomenon exhibited by pairs of color metamers <the problem of \metamerism in matching artificial with natural teeth>

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me·tam·er·ism (mə-tamґər-is″əm) 1. isomerism, particularly a type of structural isomerism in which different radicals of the same chemical type are attached to the same polyvalent element and yet give rise to compounds possessing identical molecular formulas, for example, diethylamine, (C2H5)2NH, and methyl propylamine, CH3NHC3H7. 2. arrangement into metameres by the serial repetition of a structural pattern.

Medical dictionary. 2011.

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Look at other dictionaries:

  • Metamerism — has at least three meanings: Metamerism (biology) is the property of having repeated segments, as in annelids; a concern of zoology and developmental biology The chemical property of having the same proportion of atomic components in different… …   Wikipedia

  • metamerism — metamerísm s. n. Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic  METAMERÍSM s.n. Metamerie (2) [în DN]. [cf. fr. métamérie]. Trimis de LauraGellner, 13.09.2007. Sursa: DN  METAMERÍSM s. n. 1. metamerie (2). 2. ( …   Dicționar Român

  • Metamerism — Me*tam er*ism, n. 1. (Biol.) The symmetry of a metameric structure; serial symmetry; the state of being made up of metameres. [1913 Webster] 2. (Chem.) The state or quality of being metameric; isomerism due to different bonding patterns in two… …   The Collaborative International Dictionary of English

  • metamerism — metamerism. См. сегментация. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • metamerism — [mə tam′ər iz΄əm] n. 1. [ METAMER + ISM] Chem. the type of isomerism in which chemical compounds have identical proportions of the same elements and the same molecular weight, but have radicals differing in type or position, with resulting… …   English World dictionary

  • metamerism — Two coloured materials are metamers, or form a metameric pair, when they match in colour, but the light they reflect differs in spectral composition. When this is so the surfaces will differ in colour under different incidental lighting. The… …   Philosophy dictionary

  • metamerism — metamerija statusas T sritis chemija apibrėžtis Izomerija, atsirandanti dėl heteroatomo padėties kitimo alifatinėje grandinėje. atitikmenys: angl. metamerism rus. метамерия …   Chemijos terminų aiškinamasis žodynas

  • Metamerism (color) — This article is about metamerism as it relates to colorimetry. For other meanings see the disambiguation page. In colorimetry, metamerism is the matching of apparent color of objects with different spectral power distributions. Colors that match… …   Wikipedia

  • Metamerism (biology) — Earthworms are a classic example of biological heteronomous metamery the property of repeating body segments with distinct regions In biology, metamerism is a linear series of body segments fundamentally similar in structure, though not all such… …   Wikipedia

  • metamerism — noun Date: 1833 the condition of having or the stage of evolutionary development characterized by a body made up of metameres …   New Collegiate Dictionary

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