Biological Assay

**Definition:** A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.

**Tree numbers:** - E05.091

**Synonyms:** - Bioassay - Assay, Biological - Assays, Biological - Biologic Assay - Biologic Assays