Nucleic acids are polymers of nucleotides. Ribonucleic acids (RNA) are polymers of ribonucleotides. Ribonucleotides are made up of the ribose sugar, a nitrogenous base, and phosphoric acid. The ATP (adenosine triphosphate) is a ribonucleotide. Other ribonucleotides in RNA are UTP, GTP, and CTP.