In the Griffith experient, living, pathogenic S strain bacteria are recovered fr
ID: 59838 • Letter: I
Question
In the Griffith experient, living, pathogenic S strain bacteria are recovered from a dead mouse. Where do these come from?
a. Live S strain bacteria were injected into the mouse.
b. The mouse caught live S strain bacteria through contact with other mice.
c. The heat-killed S strain bacteria came back to life inside the mouse through regeneration.
d. The heat-killed S strain bacteria somehow turned living R strain bacteria into S strain bacteria.
e. The heat-killed S strain bacteria had a small fraction of living S strain bacteria that grew up inside the mouse.
Explanation / Answer
d. The heat-killed S strain bacteria somehow turned living R strain bacteria into S strain bacteria.
Frederick Griffith’s work on Streptococcus pneumonia explained the process of bacterial transformation. Streptococcus pneumonia is a pathological bacterium that causes pneumonia in humans. He injected mice with the heat killed ‘S’ strain of the bacteria and non virulent ‘R’ strain of the bacteria, and found that the mice were attached by pneumonia. This is because of the transformation of DNA genome of heat killed bacterial strain with that of the genome of ‘R’ strain.