Explain the structure of DNA?

DNA (Deoxyribonucleic Acid) is the hereditary material found in almost all living organisms. Its structure was discovered by James Watson and Francis Crick in 1953, based on X-ray data from Rosalind Franklin.

DNA has a double helix structure, resembling a twisted ladder. Each strand of the helix is made of repeating units called nucleotides, and each nucleotide consists of three components — a phosphate group, a sugar molecule (deoxyribose), and a nitrogenous base. The four bases are adenine (A), thymine (T), cytosine (C), and guanine (G).

The bases pair specifically — A with T and C with G — through hydrogen bonds, forming the rungs of the ladder. The sugar-phosphate backbone forms the sides. The two strands run in opposite directions (antiparallel).

This structure allows DNA to store genetic information, replicate itself, and direct protein synthesis through RNA. The specific sequence of bases encodes all genetic instructions that determine an organism’s traits. DNA’s stability and precision make it the blueprint of life.