Case Study Of Frederick Griffith Experiment

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Frederick Griffith experiment:
In the early 1920’s, a young British army medical officer Frederick Griffith began studying Streptococcus pneumonia. Pneumonia, a lung infection caused by the bacterium Streptococcus pneumonia is a serious case of death at that time. Frederick Griffith was studying the possibility of creating a vaccine.
During Griffith’s experiment, his experiments suggesting that bacteria are capable of transferring genetic information through a process of transformation. He began isolating two strain of Streptococcus pneumonia, the S strain and the R strain that varied dramatically in both appearances and their ability to cause diseases. Specifically, the highly virulent S strain has a smooth capsule, the outer coat composed
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By having a capsule, it protect cells from engulfment by eukaryotic cells, such as macrophages. In other words, when S strain covers itself with a polysaccharide capsule, it protects it from the host’s immune system, resulting in the death of the host. In addition to that, R strain which is genetically identical, differ from S strain because it carries mutation that prevents it from making polysaccharide coat. According to the definition of mutation in iGenetics Third Edition page 10 under the topic of Griffith Transformation experiment, mutation is the heritable change in the genetic material. The presence of mutation in a gene affects the ability of the bacterium to make coat and changes the state of virulence of the bacterium, the R strain doesn’t have the protective capsule, so it was defeated by the host’s immune system, resulting the host to …show more content…
When an IIR bacteria injected into the mice whereby R bacteria actually taken from the mutation from IIS bacteria, the mice lived. But when the mice injected with living IIIS bacteria, the mice died. When the mice died, the living IIIS bacteria isolated from the mice’s blood. It is possible to inject the mice with IIIS bacteria and the mice will live but before injected the mice with IIIS bacteria, IIIS bacteria need to be kill by heat before

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