Because that is the shape of the molecule: two helices wrapped around each other.
Note: due to defective x-ray crystallography photos early in their work, Watson and Crick mistakenly originally reached the tentative conclusion that the DNA molecule was a triple helix with the bases pointing outward, instead of its actual shape of a double helix with the bases pointing inward and linked in pairs by hydrogen bonds.
A double helix!
The company Watson and Crick are famous for discovering the DNA Double Helix. Watson and Crick won the Nobel Prize in 1962 for their work with the DNA Double Helix.
James Watson and Francis Crick in 1953
DNA is a double helix.
Rosalind Franklin
A double helix
James Watson and Francis Crick proposed a double helix structure for DNA in 1953.
A double helix!
The molecule most associated with the names Watson and Crick is DNA, which has ... a complicated structure, if you look at the details. But the answer the question is probably looking for is "double helix".
James Watson and Francis Crick are the scientists credited with developing the double helix model of the DNA molecule in 1953. Their model revolutionized our understanding of how genetic information is stored and replicated in living organisms.
The company Watson and Crick are famous for discovering the DNA Double Helix. Watson and Crick won the Nobel Prize in 1962 for their work with the DNA Double Helix.
Watson and Crick
Watson and Crick's model of DNA showed a double helix.
Watson and Crick called the 3-dimensional shape of DNA a double helix.
They discovered the double-helix.
Watson and Crick named the shape of DNA a "double helix." This name refers to the twisted ladder-like structure of two strands of nucleotides that form the DNA molecule.
Watson and Crick's model of DNA showed a double helix.