Final answer:
The genetic information in DNA is encoded by the sequence of nucleotides, specifically the order of the nitrogenous bases (adenine, cytosine, guanine, and thymine) that make up the DNA molecule.
Step-by-step explanation:
The genetic information is coded in DNA by the sequence of the nucleotides. Each nucleotide is composed of three parts: a 5-carbon sugar, a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA: adenine (A), cytosine (C), guanine (G), and thymine (T). The sequence of these bases encodes the genetic instructions used in the development and functioning of all living organisms.
DNA's structure is that of a double helix, with the two strands running antiparallel to each other and held together by covalent bonds between the phosphate of one nucleotide and the sugar of the next, with hydrogen bonds between the complementary bases (A pairs with T; C pairs with G).