catalysis

views updated Jun 11 2018

catalysis The acceleration of a chemical or biochemical reaction that is brought about by the action of a catalyst. The catalyst, which is not affected by the overall reaction, acts by either lowering the activation energy of the reaction through a reorientation of molecules in collision, or by facilitating an alternative mechanism that has a different activation energy. Enzymes are naturally occurring catalysts which are universally present in all living cells. Enzymes are generally much more efficient and more specific than other catalysts.

catalysis

views updated May 29 2018

catalysis The acceleration of a chemical or biochemical reaction that is brought about by the action of a catalyst. The catalyst, which is not affected by the overall reaction, acts by either lowering the activation energy of the reaction through a reorientation of molecules in collision, or by facilitating an alternative mechanism that has a different activation energy. Enzymes are naturally occurring catalysts which are universally present in all living cells. Enzymes are generally much more efficient and more specific than other catalysts.

catalysis

views updated Jun 27 2018

catalysis †dissolution XVII; (chem.) chemical action brought about by a substance that remains unchanged XIX. — modL. — Gr. katálusis, f. katalúein dissolve, f. CATA- 2 + lúein loosen.
Hence catalyse, catalytic XIX, catalyst XX; after analyse, etc.

catalysis

views updated Jun 08 2018

ca·tal·y·sis / kəˈtaləsis/ • n. Chem. & Biochem. the acceleration of a chemical reaction by a catalyst.

catalysis

views updated May 18 2018

catalysis A chemical term, literally meaning ‘breaking down’, and in digestive physiology referring specifically to the breaking down of ingested food by an animal's own digestive enzymes. Compare AUTOCATALYSIS.

catalysis

views updated Jun 11 2018

catalysis The process of changing the rate of a chemical reaction by use of a catalyst.