An organic compound that is made of one or more chains of amino acids and that is a principal component of all cells
O catalyst
amino acid
complex sugar
protein

What is point source pollution of an aquatic ecosystem? a) pollution of freshwater sources b) pollution from many sources that combine into one c) pollution that occurs over a wide area; water that runs off from fields, parking lots, and other land surfaces d) pollution that can easily be identified with a single discharge source, such as an open pipe which drains into a body of water