What is one major substance that pollutes water

domestic wastes, insecticide,herbicides,food processing waste,pollunant from livestock operation,volatile organic compounds ,heavy matals , chemical waste :either one

an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme