(also uridine monophosphate), an organic substance and a nucleotide composed of residues of the pyrimidine uracil, the carbohydrate ribose, and phosphoric acid; its molecular weight is 324.2. Uridylic acid is present in all living cells and is a constituent of coenzymes involved in carbohydrate metabolism. It is one of the four basic types of monomers that make up the polymer chains of ribonucleic acids.