-Enzyme catalase is a protein enzyme present in most aerobic cells in animal tissues. Catalase is present in all body organs being especially concentrated in the liver & erythrocytes. The brain, heart, skeletal muscle contains only low amounts.
The substrate for the enzyme catalase is hydrogen peroxide. It catalyzes the decomposition of hydrogen peroxide to water and oxygen.
Explanation: The substrate would be hydrogen peroxide(H2O2) which is a reactive oxygen species or ROS. Hydrogen peroxide is dangerous because it is capable to oxidize other substance and should be broken down to water(H2O) and oxygen(O2) to prevent damaging the cell.
