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  P. A. Levene determined the basic structure of nucleotides that make up DNA.
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  Fredrick Griffith performed the first major experiment that led to the discovery of DNA.
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  Oswald Avery and his colleagues identified the molecule that transformed the R strain of bacteria into the S strain.
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  Erwin Chargaff founded the Chargaff’s rule: C=F and T=A
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  Rosalind Franklin joined King’s College and took the now famous Photo 51
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  Oswald Avery and his colleagues identified the molecule that transformed the R strain of bacteria into the S strain.
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  Linus Pauling proposed a triple helix structure for DNA
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  Watson and Crick built a model of the Double Helix and published a letter that suggested a structure for DNA.
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  Maurice Wilkins discovered the double helix structure for DNA