BIOMOLECULES AND ENZYMES

Detailed explanation-1: -In this experiment, Griffith mixed the living non-virulent bacteria with a heat inactivated virulent form. He subsequently infected mice with this mixture and much to his surprise, the mice developed pneumonia and died. Furthermore, he was able to isolate colonies of the virulent strain from these mice.

Detailed explanation-2: -Statement 1-In Griffith’s experiment, when mice were injected with heat-killed R-strain and live S-strain the mice survived.

Detailed explanation-3: -In 1928, British bacteriologist Frederick Griffith conducted a series of experiments using Streptococcus pneumoniae bacteria and mice. Griffith wasn’t trying to identify the genetic material, but rather, trying to develop a vaccine against pneumonia.

Detailed explanation-4: -So, when R-strain and heat-killed S-strain bacteria were injected separately, the mice stayed alive. But when injected together, the mice died. This was because R-strain bacteria got “transformed” into S-strain, and caused the disease. Heat-killed R-strain does not affect the mice and the mice lived.