What is the primary structure of DNA?

The primary structure of DNA is the double helix, which is composed of two long strands of nucleotides twisted around each other. Each strand consists of a backbone made from sugar and phosphate groups, with nitrogenous bases attached to the sugar molecules. The two strands are held together by hydrogen bonds between complementary base pairs (adenine with thymine and guanine with cytosine), creating a stable and specific structure that allows for the storage and transmission of genetic information.

The double helix configuration not only provides structural integrity but also enables DNA to replicate accurately during cell division and to transcribe information effectively for protein synthesis. This unique shape is crucial for the proper functioning of DNA in biological processes. The stability and efficiency of the double helix in holding genetic material distinguish it as the fundamental structure of DNA in living organisms.