Question

Hershey and Chase used radioactive isotopes to label different parts of the phage. They grew one batch of phage in the presence of the isotope 35S, and they grew another batch of phage in the presence of the isotope 32P. What part of the phage would each isotope label

Answer 1

The sulphur would lable the capsule and the phosphorous the nucleic acid.

Explanation:

Hershey and Chase experiment included growing of the pages in two batches, one in presence of 35S and other in presence of 32P. They then infected bacterial cells with these phages, cleaned them and then centrifuge the cells to isolate the marked elements in bacterial cells.

This was done to isolate which part of the phage is actually infective. Sulphur being a part of the proteins will mark the capsule whereas DNA having the phosphate bridges will be marked by 32P.