Rosalind Franklin, in full Rosalind Elsie Franklin, (born July 25, 1920, London, England—died April 16, 1958, London), British scientist best known for her contributions to the discovery of the molecular structure of deoxyribonucleic acid (DNA), a constituent of chromosomes that serves to encode genetic information.
Rosalind x-ray diffraction studies provided crucial clues to the structure of DNA and quantitatively confirmed the Watson-Crick DNA model,
Franklin earned a Ph.D. in physical chemistry from Cambridge University.
She learned crystallography and X-ray diffraction, techniques that she
applied to DNA fibers. One of her photographs provided key insights into
DNA structure. Other scientists used it as evidence to support their
DNA model and took credit for the discovery.
Franklin is best known for her work on the X-ray diffraction images of DNA, particularly Photo 51, while at King's College London, which led to the discovery of the DNA double helix for which Francis Crick, James Watson, and Maurice Wilkins shared the Nobel Prize in Physiology or Medicine in 1962.
Franklin, whose lab produced the photograph that helped unravel the mystery of DNA, received no credit for her role until after her death. Since the Nobel Prize committee doesn't confer awards posthumously, it means that Franklin will never share in the scientific community's highest honor for her work.
Photo 51
Captured by English chemist Rosalind Franklin in 1952, Photo 51 is a fuzzy X -ray depicting a strand of DNA extracted from human calf tissue — the clearest shot of life's building blocks ever seen up to that point, and the first one that seemed to prove once and for all the double-helix structure of DNA.
Franklin was instrumental to discovering there were two forms of DNA. When wet, DNA fibres became long and thin, called the B form, and when dried it became short and fat, labelled the A form. In 1951 Franklin presented this information in a lecture in Cambridge where James Watson was present. Importantly Franklin indicated that DNA was likely to be a double helix with anti parallel strands and that it had a phosphate backbone on the outside. Within this context the double bases of DNA, the code for inheritance, was envisaged to be on the inside of the helix. Franklin's notable achievement was the x-ray photographs she took of DNA, which Bernal, her former teacher, claimed were 'amongst the most beautiful x-ray photos of any substance ever taken.' Franklin's photograph, labelled 51, taken of B-DNA in 1952, was the first proof of the double helical structure of DNA. This photograph provided critical data for Crick and Watson's building of their DNA double helix model.
Many people have never heard of British scientist Rosalind Franklin. Her research helped solve the mystery of the structure of DNA - the building blocks of life
In the fall of 1956, Franklin discovered that she had ovarian cancer. She continued working throughout the following two years, and worked up until several weeks before her death on April 16, 1958, at the age of 37.
ROSALIND FRANKLIN
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