Avery,MacLeod,and McCarty (1944)demonstrated that DNA was the molecule of heredity by treating heat-killed Streptococcus pneumoniae S (smooth)strain with DNase,thereby preventing transfer of the "transforming substance" from the killed S strain to the live R (rough)strain when the two were mixed together and injected into mice.Another way that one could demonstrate transformation in bacteria would be to extract DNA from
A)an R strain and mix with cells of an S strain.
B)both S and R strains and mix to allow recombination to take place.
C)an ampicillin-sensitive strain and mix with cells of an ampicillin-resistant strain.
D)an S strain and mix with cells of an R strain.
E)none of the above

Question

Quizplus · Accepted Answer

Extracting DNA from an S strain and mixing it with cells of an R strain would demonstrate transformation, as the R strain could take up the DNA from the S strain and acquire new traits, such as virulence.

Avery,MacLeod,and McCarty (1944)demonstrated That DNA Was the Molecule of Heredity