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How do nucleic acids store genetic information in cells?

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Diagram illustrating a homopolymer arrangement using polyvinyl chloride as an example, showing a chain of identical repeating vinyl chloride units with the chemical structure highlighted. — polymer Industrial polymers are synthesized from simple compounds joined together to form long chains. For example, polyvinyl chloride is an industrial homopolymer synthesized from repeating units of vinyl chloride.

Nucleic acids store genetic information through the specific sequence and arrangement of nucleotides, which serve as the fundamental building blocks of these polymers.123

Each nucleotide consists of a phosphate group, a pentose sugar, and one of four nitrogen-containing bases. In DNA, these bases are adenine (A), guanine, cytosine, and thymine. The order of these bases along the sugar-phosphate backbone constitutes the genetic code, acting as a blueprint for the development and function of organisms.142

The physical structure of DNA as a double helix is essential to this storage function. The two strands are held together by hydrogen bonds between complementary base pairs—specifically, A always pairs with T, and G always pairs with C. This complementary pairing allows the molecule to act as a stable template for replication, ensuring that genetic information can be accurately copied and transmitted to subsequent generations.43