Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Rosalind Franklin was a British scientist whose X-ray diffraction images of DNA were critical in the discovery of its double helix structure. Her work provided key insights into the molecular structure of DNA.
5 Must Know Facts For Your Next Test
Franklin used X-ray crystallography to capture images of DNA fibers, which revealed its helical structure.
Her famous Photo 51 showed that DNA is a double helix with two strands twisted around each other.
Franklin's research indicated that the sugar-phosphate backbone of DNA lies on the outside of the molecule, while the nitrogenous bases are on the inside.
She worked at King's College London and made significant contributions to understanding viruses as well.
Although not fully recognized during her lifetime, Franklin's data and photographs greatly assisted Watson and Crick in building their model of DNA.