Dichromate within the ethanoic acid is reduced to chromic acetate when heated within the presence of peroxide (H2O2), with the formation of per chromic acid as an unstable intermediate. The chromic acetate, thus produced was measured spectrophotometrically at 570 nm. The activity of catalase within the tissue samples is expressed as µ moles of H2O2 consumed/min/mg protein (23) .