AP BIOLOGY

Detailed explanation-1: -Created by Rosalind Franklin using a technique called X-ray crystallography, it revealed the helical shape of the DNA molecule. Watson and Crick realized that DNA was made up of two chains of nucleotide pairs that encode the genetic information for all living things.

Detailed explanation-2: -Watson and Crick published their findings in a one-page paper, with the understated title “A Structure for Deoxyribose Nucleic Acid, ” in the British scientific weekly Nature on April 25, 1953, illustrated with a schematic drawing of the double helix by Crick’s wife, Odile.

Detailed explanation-3: -In addition, to publishing twenty-one papers on carbon structures and nineteen papers on viruses, Franklin is most well known for her discovery of the double helix that makes up DNA and the five publications she authored with her student, R.G. Gosling, on DNA structure (NIH).

Detailed explanation-4: -In late February 1953, Rosalind Franklin, a 33-year-old physical chemist working in the biophysics unit of King’s College in London, wrote in her notebooks that the structure of DNA had two chains. She had already worked out that the molecule had its phosphate groups on the outside and that DNA existed in two forms.