GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
living pathogenic ____ heat-killed nonpathogenic
|
|
|
heat-killed pathogenic ____ living nonpathogenic
|
|
|
living nonpathogenic ____ heat-killed pathogenic
|
|
|
living nonpathogenic ____ living pathogenic
|
Detailed explanation-1: -Experiment: Griffith injected both S and R strains to mice. The one which was infected with the S strain developed pneumonia and died while that infected with the R strain stayed alive. In the second stage, Griffith heat-killed the S strain bacteria and injected into mice, but the mice stayed alive.
Detailed explanation-2: -Transformation Experiment. Pneumococcus bacteria include two strains, a virulent S strain with a Smooth glycoprotein coat that kills mice (left), and a non-virulent R Rough strain that does not (middle). Heating destroys the virulence of S (right).
Detailed explanation-3: -Griffith’s ultimate goal was to find a way to cure pneumonia. Griffith inoculated mice with various strains of pneumococci to see if they would infect and eventually kill the mice. Griffith concluded that heat-killed virulent bacteria transformed living, non-virulent bacteria into virulent bacteria.