Question

In Hershey and Chase experiment, some viruses grew on medium that contained:

• A. ³⁵S,³²P
• B. ³⁶S,³⁴P
• C. ³²S,³⁶P
• D. ³⁴S,³⁶P

Answer 1

The Correct Option is A

In the Hershey and Chase experiment, 35S was used to label the protein coat of the bacteriophage, while 32P was used to label its DNA. This experiment demonstrated that DNA, not protein, is the genetic material, as only the 32P-labeled DNA entered the bacterial cells, while the 35S-labeled protein remained outside.

Answer 2

In the Hershey and Chase experiment (1952), the researchers used radioactively labeled isotopes to distinguish between the two components of a virus—its protein coat and its DNA. They grew viruses in mediums containing:

• 35S (Sulfur isotope) to label the protein coat of the virus because sulfur is present in proteins (specifically in methionine and cysteine).
• 32P (Phosphorus isotope) to label the DNA because phosphorus is found in DNA but not in proteins.

The experiment involved infecting bacteria with these labeled viruses and observing whether the DNA or protein entered the bacterial cells. This experiment provided strong evidence that DNA, not protein, is the genetic material that is transferred into bacterial cells during infection.