What was the purpose of Frederick Griffith's studies?

Answer 1

He found out what made people sick.

In more detail, he reported his Griffith Experiment, which was the first widely accepted demonstration of bacterial transformation. He showed that Streptococcus pneumonae could transform from one strain to another, an observation that was attributed to an unidentified transforming principle or factor that was later identified as DNA.

Answer 2

Griffith discovered transformation. Transformation is what we would today describe as the motion of DNA from one cell to another. But in those days, it was not known that DNA was the genetic material. All that was known was that something caused transformation.

S virulent strains of Streptococcus pneumoniae were injected into mice. The mice promptly perished from pneumonia due to the bacterial virulence. Second, mice had R nonvirulent strain of Streptococcus pneumoniae injected. The mice were fine afterwards due to the nonvirulence of the bacterium. Heat killed S virulent bacteria had no effect either. However something rather sinister happened when S virulent (heat killed) and R nonviruent were mixed in together and entered the mice.

The S virulent were dead and could do nothing. But it appeared a transforming medium must have traversed from them to the R nonvirulent (live) strain. The R nonvirulent became S virulent and killed the mice ferociously. Something very odd had happened. A transforming principle. Transformation had been discovered.

nicely put, but you missed some points.

Fredrick Griffith was a bacteriologist who discovered transformation. Transformation is what we would today explain as the movement of DNA from one cell to another. But back in those days, DNA was not known as a genetic material; all they know was that something caused transformation. In his experiment, Griffith found that if the dangerous S bacteria strains of Streptococcus pneumonia (that he put in a capsule to stop the bodies defense systems) were injected into mice, then the mice quickly died from pneumonia because of the bacterial poisoning. The other mice that were infected with the R bacteria were fine. In order to see if the capsules were killing the mice, Griffith injected dead S bacteria in the mice, but that had no effect. So, afterwards, he injected the mice with heat-killed S bacteria, but that had no effect either. So now, Griffith knew that the capsule did not kill the bacteria. The purpose of the heat-killed bacteria was so they could no longer reproduce. However something pretty disturbing happened when the previously harmless heat-killed S bacteria and previously harmless R bacteria were mixed in together and injected into the mice, the mice died. Griffith, mystified, checked the blood of the dead mice and found that the harmless R bacteria had aqquierd capsules. So, in other words the harmless R bacteria had become the harmful S bacteria. Griffith had discovered what we now call "transformation".

Answer 3

Frederick Griffith's studies aimed to investigate the transformation of nonvirulent bacteria into virulent bacteria. He conducted experiments with Streptococcus pneumoniae to understand how genetic information could be transferred between different bacterial strains. This work laid the foundation for the discovery of DNA as the genetic material.

Answer 4

Griffith had discovered what is now called Transformation, trasformation is a change in genotype caused when cells take up foreign genetic material.

Answer 5

To show that bacteria were not fixed and could take in foreign DNA to change their phenotype and genotype.

Answer 6

Attempted to create a vaccine against ammonia, but instead stumbled across the transforming principle which later helped in the discovery of DNA.