1
Question
Pneumococcus experiment done by Frederick Griffith proves that
Pneumococcus experiment done by Frederick Griffith proves that
Open in App
Solution
The correct option is A DNA is the genetic material
The transformation experiments conducted by Frederick Griffith in 1928, are of greater importance in establishing the nature of genetic material and prove that DNA is genetic material. He used two strains of bacterium pneumococcus (Streptococcus pneumoniae), viz., S and R.
• Smooth (S) or capsulated type: They have a mucous coat and produce shiny colonies. These bacteria are virulent and cause pneumonia.
• Rough (R) or non-capsulated type: Mucous coat is absent in them. They produce rough colonies. These bacteria are nonvirulent and do not cause pneumonia.
In this experiment, bacteria from the S strain were killed by heat, and their remains were added to R strain bacteria. While neither alone harmed the mice, the combination was able to kill its host. Griffith was also able to isolate both live R and live S strains of pneumococcus from the blood of these dead mice. Griffith concluded that the type R had been "transformed" into the lethal S strain by a "transforming principle" that was somehow part of the dead S strain bacteria. The substance that lead to the transformation was later confirmed to be DNA from further experiments. Hence, the correct answer is option a.
The transformation experiments conducted by Frederick Griffith in 1928, are of greater importance in establishing the nature of genetic material and prove that DNA is genetic material. He used two strains of bacterium pneumococcus (Streptococcus pneumoniae), viz., S and R.
• Smooth (S) or capsulated type: They have a mucous coat and produce shiny colonies. These bacteria are virulent and cause pneumonia.
• Rough (R) or non-capsulated type: Mucous coat is absent in them. They produce rough colonies. These bacteria are nonvirulent and do not cause pneumonia.
In this experiment, bacteria from the S strain were killed by heat, and their remains were added to R strain bacteria. While neither alone harmed the mice, the combination was able to kill its host. Griffith was also able to isolate both live R and live S strains of pneumococcus from the blood of these dead mice. Griffith concluded that the type R had been "transformed" into the lethal S strain by a "transforming principle" that was somehow part of the dead S strain bacteria. The substance that lead to the transformation was later confirmed to be DNA from further experiments. Hence, the correct answer is option a.
Suggest Corrections
0
Similar questions
View More
Join BYJU'S Learning Program
Explore more
Join BYJU'S Learning Program
