Crick and Watson's double helix

Crick and Watson's double helix model describes the structure of DNA, the molecule that carries genetic information. They proposed that DNA consists of two long strands twisted around each other, resembling a spiral staircase. Each strand is made up of smaller units called nucleotides, which are composed of a sugar, a phosphate group, and a nitrogenous base. The sequence of these bases encodes genetic information, while the strands are held together by base pairs (adenine with thymine, and cytosine with guanine). This elegant structure allows DNA to replicate and transmit genetic information across generations.