The Hershey and Chase experiments involved the preparation of two different types of radioactively labeled phage. Which of the following best explains why two preparations were required?

A. Establishing the identity of the genetic material required observation of two phage generations.
B. The bacteriophage used in the experiments was a T2 phage.
C. It was necessary that each of the two phage components, DNA and protein, be identifiable upon recovery at the end of the experiment.
D. Each scientist had his own method for labeling phage, so each conducted the same experiment using a different isotope.

Explanation:

Alfred Hershey and Martha Chase performed an experiment to identify the chemical nature of the genetic material.

After completion of the experiment, they found that DNA is a genetic material and not protein.

In this experiment, bacteriophage was used that is made up of DNA and protein so it was necessary to identify protein as well as DNA so both were labeled separately.

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i think the answer is b.