The following diagram depicts lactase catalyzed cleavage of lactose. Glu-1749 is the side chain of the active site glutamate amino acid in the lactase enzyme. Lactose is a disaccharide; it is composed of a galactose and a glucose. Downregulated lactase expression results in lactose intolerance. Please analyze the following diagram carefully, and choose the statement which describes it best.

MCQS on the biological importance of organic molecules. Topics include bioorganic mechanisms, chirality, lipids, carbohydrates, animo acids, peptides, proteins, nucleic acids, enzymes, coenzymes, and coupled reactions, and lipid, carbohydrate, amino acid, and nucleotide metabolism.