Identify the correct sequence of steps involved in the Hershey-Chase experiment.
(A) Centrifugation
(B) Attachment of bacteriophage to bacteria
(C) Blending
(D) Infection
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (B), (D), (C), (A)
(B) Attachment of bacteriophage to bacteria — first. Hershey and Chase grew viruses with either radioactive DNA (32P) or radioactive protein (35S). These viruses were allowed to attach to E. coli bacteria.
(D) Infection — second. The attached virus injects its genetic material into the bacterium. The empty protein coat stays outside.
(C) Blending — third. As soon as infection took place, the bacteria were agitated in a blender. This removed the viral coats from the bacteria.
(A) Centrifugation — last. Spinning in a centrifuge separated the heavy bacteria from the light viral particles. Bacteria infected with 32P viruses were radioactive, while those with 35S viruses were not. So DNA, not protein, had entered the bacteria and is the genetic material.
NCERT Extract:
The Genetic Material Is DNA – …
