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Who Discovered DNA Timeline

By schultze20

  • Phoebus (P.A.) Levene

    Phoebus (P.A.) Levene
    He was biochemist who studied the structure and function of nucleic acids. He characterized the different forms of nucleic acid, DNA from RNA, and found that DNA contained adenine, guanine, thymine, cytosine, deoxyribose, and a phosphate group.

  • Frederick Griffith

    Frederick Griffith
    In 1928 Frederick Griffith was working on a project that enabled others to point out that DNA was the molecule of inheritance. He used mice and two types of pneumonia. Griffith had discovered what is now called Transformation, transformation is a change in genotype caused when cells take up foreign genetic material.

  • Oswald Avery

    Oswald Avery
    In 1944 he discovered DNA is the material of which genes and chromosomes are made.

  • Rosalinda Franklin

    Rosalinda Franklin
    X-ray diffraction images of DNA which formed a basis of Watson and Crick's hypothesis of the double helical structure of DNA in their 1953 publication

  • Maurice Wilkins

    Maurice Wilkins
    He took the first images of DNA, producing pictures of X-ray diffraction in aligned fibres of DNA (the double helix).

  • Alfred Hershey and Martha Chase

    Alfred Hershey and Martha Chase
    The Hershey-Chase experiment was a series of experiments conducted in 1952 by Alfred Hershey and Martha Chase. It identified DNA to be the genetic material of phages and, ultimately, of all organisms.

  • Erwin Chargaff

    Erwin Chargaff
    Chargaff showed that in DNA the number of guanine units equals the number of cytosine units and the number of adenine units equals the number of thymine units.

  • James Watson and Francis Crick

    James Watson and Francis Crick
    They discovered that DNA was a double helix.

  • Linus Pauling

    Linus Pauling
    Pauling developed the theory of the molecular clock, which enables one to judge the separation in time between two species by looking at the number of differences in their hemoglobin proteins.

  • Cited Sources

    http://www.xtimeline.com/evt/view.aspx?id=718276 http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1954/pauling-bio.html http://www.sdsc.edu/ScienceWomen/franklin.html http://www.nature.com/scitable/topicpage/discovery-of-dna-structure-and-function-watson-397 http://www.history.com/this-day-in-history/watson-and-crick-discover-chemical-structure-of-dna