ex vivo method enzyme or transport activity assay 2013-12-20T10:39:06Z A procedure or technique performed outside the living body by which the catalytic activity of an enzyme (a protein that catalyzes chemical reactions of other substances without itself being destroyed or altered upon completion of the reactions) or activity of a transport molecule or complex is assessed and a quantitative or qualitative value assigned. JSmith MMO:0000444 PMID:12887131 PMID:3611769 measurement_method_ontology