Define transformation in Griffith's Experiment Discuss how it helps in the identification of DNA as genetic meterial.

Explanation

Transformation is defined as the uptake of a naked DNA molecule, of the fragments of a bacterial cell and the incorporation of this DNA molecule into the recepient chromosome in a heritable form.
In 1928 Frederick Griffith perforțed the experiments on Bacterial transformation with Streptococcus pneumonia the bacterium causing pneumonia. During the course of his experiment he found that a living organism. (bacteria) could change in physical form.
1. He observed two stains of this bacterium,one forming smooth . colonies with capsule (S-type) and the other forming rough colonies without capsule (R-type):
2. The S-type cells are virulent while R-type cells are non-virulent.
3. When live S-type cells are’injected into the mice, they suffered from pneumonia and died.
4. When live R-type cells are injected into the mice, the did not appear and the mice survived.
5. "When heat killed S-type cells were injected, the disease did w not appear.
6. When heat killed S-type were mixed with live R-type cells and injected into the mice, the mice died of .pneumonia and live S-type cells were isolated from the body of mice.
7. He concluded that the R-strain had some how been transformed by the heat killed S-strain bacteria, which must be due to the transfer of genetic material the transforming principle.