What is the structure of DNA?

The structure of DNA is accurately described as a double helix formed by nucleotide pairs. This means that DNA consists of two long strands that twist around each other, resembling a spiral staircase. Each strand is composed of nucleotides, which are the building blocks of DNA. Each nucleotide contains three components: a phosphate group, a sugar molecule (deoxyribose), and a nitrogenous base.

In the double helix structure, the nitrogenous bases on each strand pair with complementary bases on the opposite strand: adenine pairs with thymine, and cytosine pairs with guanine. This base pairing is crucial for the stability of the DNA structure and for accurate replication during cell division. The double helix structure allows DNA to store genetic information efficiently and ensures that it can be unwound and copied when necessary.

Understanding this structure is fundamental to grasping how genetic information is encoded, replicated, and passed on in living organisms.