Molecular models of DNA simulations that are very important to understand how DNA functions "in vivo". From the very early stages of structural studies of DNA by X-ray diffraction and biochemical means, molecular models such as the Watson-Crick nucleic acid double helix model were successfully employed to solve the 'puzzle' of DNA structure, and also find how the latter relates to its key functions in living cells. The first high quality X-ray diffraction patterns of A-DNA were reported by Rosalind Franklin and Raymond Gosling in 1953. Rosalind Franklin made the critical observation that DNA exists in two distinct forms, A and B, and produced
Francis Crick structure of DNA. Orgel also later worked with Crick at the Salk Institute for Biological Studies. Soon after Crick's death, there have been allegations about him having used LSD when he came to the idea of the helix structure of the DNA. While he almost certainly did use LSD, it is unlikely that he was doing that as early as 1953. In 1954, at the age of 37, Crick completed his Ph.D. thesis: ""X-Ray Diffraction: Polypeptides and Proteins"" and received his degree. Crick then worked in the laboratory of David Harker at Brooklyn Polytechnic Institute, where he continued to develop