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miescher
Miescher found the DNA by isolating and characterizing the protein components of white blood cells. During this process, he saw a substance with unusual components and chemical properties unlike the proteins he was searching for. He realized that this was a new substance. At that time, he'd called DNA "nuclein", but now we call this "nuclein" DNA. -
chargaff
Chargaff discovered that there were 4 nucleotide bases in human DNA. He also discovered the ratio of the 4 DNA bases. He called the Ratio Chargaff's rule. In his rules, he stated that purines and pyrimidines were equal or about equal in quantity. He also discovered that the composition of DNA various between species. Before chargaffs discovery, It was not known that the Bases were similar in quantity. -
Franklin
Franklin lead the way in terms of research of the structure of DNA. She found this while working at Cambridge University. when viewing the structure of the DNA fibres through x-rays, she calculated the dimensions of the DNA strands and said that there were phosphates attached to a structure that was helical in shape. -
Hershey and Chase
Hershey and Chase discovered that DNA is genetic material . They used an experiment with genetic material of bacteriophage. Hershey and Chase used a trace chemical in a fast reproducing virus called TZ. The evidence provided that the tracers were to be found in future generations of the cells TZ infected. -
Watson and Crick
Watson and Crick discovered that DNA was shaped like a double helix. They used available x-ray data to find the shape of the DNA. They saw how chargaff's rule was applied and how it made sense.Watson and Crick also saw how the 2 strands of DNA were connected in the DNA. -
Meselson and stahl
Proved that DNA was replicated semiconserverately. They discovered this by using the technique of density gradient configuration. Meselson and stahl cultured bacteria in a heavy isotope of nitrogen, and tested them at 3 different cycles. After 2 different cycles, they saw 2 DNA bands one of intermediate density and one of light density, showing that DNA was replicated semiconserverately -
Works cited
DNA Worldwide Group. "The History of DNA Timeline." DNA Worldwide. DNA Worldwide, 30 Sept. 2015. Web. 24 Jan. 2017.
Website Pearson Inc. "Pearson - The Biology Place." Pearson - The Biology Place. Pearson Inc., 2016. Web. 24 Jan. 2017. University of Arizona. "Nucleic Acids and the Genetic Material Problem Set." Nucleic Acids and the Genetic Material Problem Set. University of Arizona, 1996. Web. 24 Jan. 2017.
