What was Griffith's Experiment?
Q: What was Griffith's Experiment?
A: Griffith's Experiment was an experiment done in 1928 by Frederick Griffith. It was one of the first experiments showing that bacteria can get DNA through a process.
Q: What did Griffith use for his experiment?
A: For his experiment, Griffith used two strains of Streptococcus pneumoniae, a type III-S (smooth) and type II-R (rough) strain.
Q: How did the experiment work?
A: In the experiment, bacteria from the III-S strain were killed by heat, and their remains were added to II-R strain bacteria. While neither harmed the mice on their own, the blend of the two was able to kill mice.
Q: What did Griffith conclude from his results?
A: From his results, Griffith concluded that the type II-R had been "transformed" into the lethal III-S strain by a "transforming principle" that was somehow part of the dead III-S strain bacteria.
Q: Who later confirmed what this transforming principle actually is?
A: Avery, McLeod and McCarty as well as Hershey and Chase later confirmed that this transforming principle is actually DNA from the III-S strain bacteria.
Q: How does this transformation occur?
A: The transformation occurs when DNA from the III-S strain survives heating and is taken up by II-R strain bacteria. This gives them genes which form a protective shield around them so they are protected from attack by host immune systems and can then kill hosts.
