PRINCIPLES OF TOXICOLOGY - Biology East Borneo

GLOSSARY 573tolerance The ability of an organism to show less response to a specific dose of a chemical than itshowed on a prior occasion when subjected to the same dose.totipotency The ability of a cell, such as an egg, to give rise to unlike cells and thus to develop intoor generate a new organism or part.toxicity A relative term generally used in comparing the harmful effect of one chemical on somebiologic mechanism with the effect of another chemical.toxicology The scientific study of poisons and their actions and detection, and treatment of thecondition produced by them. Also the study of the effects of chemicals on biologic systems, withemphasis on the mechanisms of harmful effects of chemicals and the conditions under whichharmful effects occur. Thus, toxicology is a multidisciplinary science.tracheitis Inflammation of the trachea.tumor An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that ofnormal tissue. The basic types are benign and malignant. See also benign tumor; malignanttumor.tumorigenicity The process or quality of producing or giving rise to a tumor.Type I reaction (immediate) A hypersensitive reaction that is manifested in allergic asthma, hayfever, and excema, developing within minutes after exposure to an antigen.type II reaction (antibody-mediated) A hypersensitive reaction that is caused by an antibodyreaction to cell surface antigens; occurs when red blood cells are destroyed in transfusion reactions.ubiquinone A quinone compound that serves as a electron carrier between flavoproteins and incellular respiration.uncertainty factor See safety factor.unction An ointment; the application of an ointment or salve.uropathy Any pathologic change in the urinary tract.Urticarria See hives.ventricular fibrillation Arrhythmia characterized by fibrillary contractions of the ventricular muscleowing to rapid repetitive excitation of myocardial fibers without coordinated contraction of theventricle.xenobiotic A chemical foreign to the biologic system (i.e., chemicals that are not normal endogenouscompounds for the biologic system).