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Molecular Basis of Heredity: Part 1. Nucleic Acids

Author(s): Raye L. Alford, PhD

The Molecular Components of DNA and RNA (I)

The atoms that make up DNA and RNA are organized into two primary molecular components: bases and pentose sugars with attached phosphate groups. The bases are the key informational components of DNA and RNA, the letters of the DNA and RNA alphabet. The bases of DNA include adenine (A), cytosine (C), guanine (G), and thymine (T). Each base consists of a nitrogen-containing component called an amine. The side groups attached to the amines differ among the bases. Although RNA also uses A, C, and G, RNA does not use T. Instead, RNA substitutes the base uracil (U) for T.