The double helix is a description of the molecular shape of a double-stranded DNA molecule. In 1953, Francis Crick and James Watson first described the molecular structure of DNA, which they ...

(Image: Wikimedia Commons, CC SA 3.0) The most common type of base pairing is the Watson-Crick base pair, named after James Watson and Francis Crick, who first proposed the double helix structure of ...

so that matching base pairs interlocked in the middle of the double helix to keep the distance between the chains constant. Watson and Crick showed that each strand of the DNA molecule was a ...