Yu Sun Park. Dr. Murphy. Lab Section 4. Discovery Of Dna

Yu Sun Park Dr. Murphy Lab section 4 Discovery of DNA double helix: Related to both Scientific and Humane Aspects DNA, the molecule of life that carries genetic information in humans and almost all other organisms, has been considered as one of the greatest discoveries until now. If DNA could not have been discovered, we would not be able to do or test numerous things such as paternity test and pathological confirmation. There are four main scientists who contributed their lives, knowledge, and ambitions to find out the DNA double helix, a DNA molecule that has two strands winding around each other: James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin. Throughout historical backgrounds and environments, their discovery of†¦show more content†¦In 1952, Linus Pauling, who was eager to know the shape of DNA, had published a paper about his proposal of a triple-helical structure for DNA (Watson 54). Following Pauling, Watson and Crick also worked on the triple-helical model, but according to the X-ray data, the theory for the triple-helical structure, where phosphates form th e helical core with the bases pointing outwards, was failed to show the correct structure of DNA (Watson 54). It was Franklin’s diffraction photograph â€Å"Photo 51† that finally showed the helical structure of DNA to Watson and Crick. The photo that had been crystallized under moist conditions shows a fuzzy X in the middle of the molecule with a helical structure. She also found out that DNA exists in two different forms, A and B. A is drier crystal in that contain 20 percent water, whereas B is less ordered and fully hydrated (NOVA). However, the mistake that Franklin made was that she thought X-rays were the only way to find the structure of DNA (Watson 69). She thought making models of DNA and playing with them were not that efficient and were a waste of time (Watson 69). In addition, she also thought the method of Watson and Crick using light beam to take a picture of DNA and calculating the lines was ineffective because she thought calculations take too long (NOVA). Also, in â€Å"Photo 51,† Franklin did not notice about the helical structure and how the nitrogeno us bases are paired (Elkin 44). If she thought of different methods