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 ...

In 1953, Francis Crick and James Watson described the molecular shape of DNA as a "double helix." Double-stranded DNA is composed of two linear strands that run opposite to each other, known as ...

Normally these letters combine in pairs to form the well-known double helix shape. However, some small lengths of DNA can exist as alternative shapes, which can affect how the instructions of the DNA ...