Substances that act as a catalyst to bring a specific chemical reaction are called enzymes. Substrates join together with the enzymes in the active site. The enzyme then catalyzes the chemical reaction to split or combine the substrate to create a new product, which is occurred due to the lowering of activation energy. Environmental conditions that affect how well enzymes works are temperature, pH, enzyme concentration, substrate concentration, and presence of inhibitors/activators. Catalase is an enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen. The purpose of catalase in living cells is to protect them from oxidative damage which can occur when cells or other molecules in the body come into contact with oxidative