Question

Choose the correct answers from the alternatives given :
The experiment which shows that DNA is the genetic material in bacteriophages is the

• A. Meselson-Stahl experiment
• B. Hershey-Chase experiment
• C. Franklin-Wilkins experiment
• D. Watson-Crick experiment

Answer 1

The correct option is B Hershey-Chase experiment

The Hershey-Chase experiment confirmed that DNA is the genetic material. They showed that when bacteriophages, which were composed of DNA and proteins, infect bacteria, most of the DNA enters the bacterial cell but the proteins do not.

The sulphur in the proteins and phosphorous in DNA was labelled and the bacteriophages were allowed to infect the unlabelled bacteria. The phage coats remained on the outside of the bacteria, while the DNA entered. Agitation was done to disrupt the phage from the bacteria. This was followed by centrifugation for the separation of the phage coats from the bacteria. These bacteria were then lysed to release the progeny of the viruses. The new progeny formed had phosphorous labelled DNA, while the protein coat was unlabelled. This proved that DNA is the genetic material in bacteriophages.

So, the correct option is 'Hershey-Chase experiment'.