How We Discovered DNA

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Prior to watching the TED Talk “How We Discovered DNA” by James Watson, I understood the concepts regarding, and utilizing, DNA in classes while completing my cellular biology degree; however, I was never taught how DNA was discovered. I learned that DNA was initially discovered to have a structure through crystallography. Scientists discovered that there are four common nucleotides in DNA and that each adenine is paired with a guanine while each cytosine is paired with thymine. Tests were developed to determine the abundance of each nucleotide in the DNA strand, and ultimately, scientists have been able to determine the exact sequence of DNA strands. They found that the four bases are held together by hydrogen bonds between the phosphate groups, thus resulting in an alpha-helical structure. It was hypothesized that since the bases had a particular “partner”, DNA strands can have different sequences depending on the ultimate function of the DNA strand. While watching the TED Talk by James Watson, I found it interesting at how trying the entire process was of discovering DNA to figuring out …show more content…

After some research, I was able to find that Johann Friedrich Miescher discovered nucleic acids and nucleotides, which allowed scientists to determine the composition and structure of the DNA. While Erwin Chargaff was able to determine the composition of adenine, thymine, cytosine, and guanine, Watson and Crick were able to establish that DNA is antiparallel in order to allow for the bases to correctly base pair and to allow for replication (Discovery of the Structure of DNA). The base pair system could not be broken since adenine and thymine are bonded by two hydrogen bonds while cytosine and guanine are bonded by three hydrogen bonds; this supported Chargaff’s claim that there would always be an equal amount of adenine and thymine, as well as cytosine and guanine (The Structure of

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