Dolly (Sheep)
The start to a new section would have to be with the illustrious sheep, Dolly. Cloned, this sheep was a medical breakthrough conjured by the amazing scientist Ian Wilmut. Only able to live to age 6, she was the prime example of animal cloning, giving us an understanding of the risks and possibilities. Earlier discovery of things such as DNA and bacteria were instrumental in making Dolly possible.
Frederick Griffith wanted to develop a vaccine against Streptococcus pneumonia. His research would ultimately shed a bit of light on the mechanisms of heredity, even though he was never able to successfully develop the vaccine he was searching for. He found that when the rough strain of Streptococcus was applied to a rat it would no cause an effect, but when the smooth strain was added the mouse died. He decided to see if the rat would be affected by the smooth if he heat-killed it. This worked but one more test would be needed for him to be sure. He would add heat-killed smooth strains with living r-strains, but the rat died. Why did this happen? Well it seemed that the R strain had absorbed the DNA of the diseased S strain.
Griffith’s experiments would later influence later scientists such as Oswald Avery to find an ultimate cure to these bacterial infections. Bacteria cause many lethal diseases and strike fear into people’s hearts. As bad as bacterial infections are, viruses may be even worse. A virus is a microscopic particle (ranging in size from 20 – 300 nm) that can infect the cells of a biological organism. Viruses can replicate themselves only by infecting a host cell. They therefore cannot reproduce on their own. When a virus takes over a bacteria it is knows as a bacteriophage. The experiments on bacteria and viruses led to Watson and Crick’s work in determining the exact structure of DNA. It took them much time and effort building and rebuilding models and badgering chemist until they finally discovered the exact...
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