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Miescher
Miescher isolated the nuclein, DNA with associated proteins, from cell nuclei. He was the first to identify DNA as a distinct molecule. He isolated various phosphate-rich chemicals, which he called nuclein, from the nuclei of white blood cells. He later raised the idea that the nucleic acids could be involved in hereditary. Miescher paved the way for the identification of DNA a the carrier of inheritance. -
Franklin
Franklin discovered that DNA was double stranded. She discovered this when looking through s microscope, there were two forms of DNA shown in the X-ray images. She noted that one of the form images appeared to show a definite helical structure and that there where two clear strands visible in the image. Franklin believed that Watson's and Crick's model wad based more on conjecture where her model wad based on solid evidence. -
Chargaff
Through careful examination, Chargaff proposed two main rules in his lifetime, which were named Chargaff's rules. His first achievement was to show that in natural DNA the number if guanine equals the number of cytokine and the number of adenine equals the number of Thymine. The second rule was that the amounts of guanine, cytosine, adenine and thymine bases varies from each species. His research helped the Watson and Crick laboratory team to deduce the double helical structure of DNA. -
Hershy and Chase
Hershey and Chase concluded through experiments that DNA, not protein, was the genetic material. They determined that internal DNA is what conferred its ability to produce progeny inside a bacterium. Many scientist still assumed that proteins carried the information for information for inheritance because DNA appeared simpler than proteins. They conducted a series of experiments that helped to confirm that DNA is genetic material. -
Watson & Crick
Watson and Crick discovered the double helix, the twisted ladder structure of deoxyribonucleic acid, or, DNA. This discovery is largely concerned with understanding how genes control the chemical process within cells. Their discovery yielded ground breaking insights into the genetic code and protein synthesis. They used cardboard cutouts representing the individual chemical components of the four bases and shifting them around on their desktops. -
Meselson and Stahl
Midseason and Stahl created the Meselson-Stahl experiment, which supported the hypothesis that DNA replication was semiconservative. Since nitrogenous is found in the nitrogenous bases of each nucleotide, they decided to use an isotope of nitrogen to distinguish between parent and newly copied DNA. The isotope of nitrogen had an extra neutron in the nucleus, which made it heavier.
