Hydrogenase - Hygiene

hydrogenase

(hī′drō-jĕn-ās) An enzyme that catalyzes reduction by molecular hydrogen.

hydrogenate

(hī′drō-jĕn-āt″) To combine with hydrogen.

hydrogenation

(hī″drō-jĕn-ā′shŭn) A process of changing an unsaturated fat to a solid saturated fat by the addition of hydrogen in the presence of a catalyst.

hydrokinetics

(hī″drō-kī-nĕt′ĭks) [″ + kinesis, movement] The science of fluids in motion.

hydrolase

(hī′drō-lās) An enzyme that causes hydrolysis.

hydrology

(hī-drŏl′ō-jē) [″ + logos, word, reason] The scientific study of water. It is considered one of the earth sciences.

hydrolysate

(hī-drŏl′ĭ-sāt) That which is produced as a result of hydrolysis.

 protein h. The amino acids obtained from splitting proteins by hydrolysis; used as a source of amino acids in certain diets.

hydrolysis

(hī-drŏl′ĭ-sĭs) [″ + lysis, dissolution] Any reaction in which water is one of the reactants, more specifically the combination of water with a salt to produce an acid and a base, one of which is more dissociated than the other. It involves a chemical decomposition in which a substance is split into simpler compounds by the addition or the taking up of the elements of water. This kind of reaction occurs extremely frequently in life processes. The conversion of starch to maltose, of fat to glycerol and fatty acid, and of protein to amino acids are examples of hydrolysis, as are other reactions involved in digestion. A simple example is the reaction in which the hydrolysis of ethyl acetate yields acetic acid and ethyl alcohol: C₂H₅C₂H₃O₂ + H₂O = CH₃COOH+C₂H₅OH. Usually such reactions are reversible; the reversed reaction is called esterification, condensation, or dehydration synthesis. SEE: assimilation; enzyme.

hydrolytic

(-drō-lĭt′ĭk), adj.

hydrolyze

(hī′drō-līz) To cause to undergo hydrolysis.

hydroma

(hī-drō′mă) [Gr. hydor, water, + oma, tumor] Hygroma.

hydromassage

(hī″drō-mă-săzh′) Massage that is performed either underwater or with water pressure applied to the body.

hydromeiosis

(hī″drō-mī-ō′sĭs) [″ + meiosis, dimunition] The swelling of the epidermis after it is exposed to water, with consequent blockage of the sweat ducts. This phenomenon limits fluid loss from sweating when the body is immersed in water.

hydromeningitis

(hī″drō-mĕn″ĭn-jī′tĭs) [″ + meninx, membrane, + itis, inflammation] 1. An inflammation of membranes of the brain with serous effusion. 2. An inflammation of Descemet's membrane.

hydromeningocele