What is the basic structure of DNA?

The basic structure of DNA is a double helix, which consists of two strands of nucleotides twisted around each other. Each nucleotide is composed of a phosphate group, a sugar molecule (deoxyribose in the case of DNA), and a nitrogenous base (adenine, thymine, cytosine, or guanine). The double helix shape is stabilized by hydrogen bonds between complementary bases on the opposite strands, with adenine pairing with thymine and cytosine pairing with guanine.

This structural arrangement allows DNA to store genetic information efficiently and provides mechanisms for replication and expression of genes. The double helix was famously described by James Watson and Francis Crick, building upon earlier work by Rosalind Franklin and others who studied the properties of DNA. The uniqueness of its helical form, along with the specific pairing of bases, is crucial for the fidelity of genetic inheritance and cellular function.