catabolism

catabolic /kat'euh bol"ik/, adj.catabolically, adv.
/keuh tab"euh liz'euhm/, n. Biol., Physiol.
destructive metabolism; the breaking down in living organisms of more complex substances into simpler ones, with the release of energy (opposed to anabolism).
[1875-80; < Gk katabol(é) a throwing down (kata- CATA- + bolé a throw; cf. katabállein to throw down) + -ISM]

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      the sequences of enzyme-catalyzed reactions by which relatively large molecules in living cells are broken down, or degraded. Part of the chemical energy released during catabolic processes is conserved in the form of energy-rich compounds (e.g., adenosine triphosphate [ATP]).

      Energy is released in three phases. In the first, such large molecules as those of proteins, polysaccharides, and lipids are broken down; small amounts of energy are released in the form of heat in these processes. In the second phase, the small molecules are oxidized, liberating chemical energy to form ATP as well as heat energy, to form one of the three compounds: acetate, oxaloacetate, or α-oxoglutarate. These are oxidized to carbon dioxide during the third phase, a cyclic reaction sequence called the tricarboxylic acid (or Krebs) cycle. Hydrogen atoms or electrons from the intermediate compounds formed during the cycle are transferred (through a succession of carrier molecules) ultimately to oxygen, forming water. These events, the most important means for generating ATP in cells, are known as terminal respiration and oxidative phosphorylation.

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Universalium. 2010.

Look at other dictionaries:

  • catabolism — CATABOLÍSM s.n. Proces biologic de transformare a unor substanţe complexe, specifice organismului, în alte substanţe mai simple şi nespecifice, pe care organismul le elimină; dezasimilaţie, dezasimilare. – Din fr. catabolisme. Trimis de valeriu,… …   Dicționar Român

  • catabolism — n. the breakdown of more complex substances into simpler ones with release of energy, in living organisms; destructive or downward metabolism; a form of metabolism, opposed to {anabolism}. See also {Disassimilation}. [Formerly spelled… …   The Collaborative International Dictionary of English

  • catabolism — catabolism. См. диссимиляция. (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.

  • catabolism — (n.) 1876, katabolism, destructive metabolism, from Gk. katabole a throwing down (also a foundation ), from kataballein to throw down, from kata down (see CATA (Cf. cata )) + ballein to throw (see BALLISTICS (Cf …   Etymology dictionary

  • catabolism — ► NOUN ▪ the breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy. The opposite of ANABOLISM(Cf. ↑anabolism). DERIVATIVES catabolic adjective. ORIGIN from Greek katabol throwing down …   English terms dictionary

  • catabolism — [kə tab′ə liz΄əm] n. [< CATA + Gr bolē, a throw < ballein, to throw (see BALL2) + ISM] the process in a plant or animal by which living tissue is changed into energy and waste products of a simpler chemical composition; destructive… …   English World dictionary

  • Catabolism — For the related metabolic process, see anabolism. Catabolism is the set of metabolic pathways which break down molecules into smaller units and release energy. [cite web |url=http://www.chem.qmul.ac.uk/iupac/bioinorg/CD.html#8 |title=Glossary of… …   Wikipedia

  • catabolism — Metabolism Me*tab o*lism, n. (Physiol.) 1. The act or process, by which living tissues or cells take up and convert into their own proper substance the nutritive material brought to them by the blood, or by which they transform their cell… …   The Collaborative International Dictionary of English

  • catabolism — Disassimilation Dis as*sim i*la tion, n. (Physics) The decomposition of complex substances, within the organism, into simpler ones suitable only for excretion, with evolution of energy, a normal nutritional process the reverse of assimilation;… …   The Collaborative International Dictionary of English

  • catabolism — katabolizmas statusas T sritis chemija apibrėžtis Metabolizmo fazė. atitikmenys: angl. catabolism; dissimilation rus. диссимиляция; катаболизм ryšiai: sinonimas – disimiliacija …   Chemijos terminų aiškinamasis žodynas

  • catabolism — noun Etymology: Greek katabolē throwing down, from kataballein to throw down, from kata + ballein to throw more at devil Date: 1876 degradative metabolism involving the release of energy and resulting in the breakdown of complex materials (as… …   New Collegiate Dictionary

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