Q.Hershey and Chase's experiment with bacteriophage showed that :

By separately radiolabelling phage DNA and phage protein and tracking which one entered bacterial cells and produced new phage progeny, Hershey and Chase conclusively demonstrated that DNA (not protein) is the hereditary material.

Alfred Hershey and Martha Chase, in 1952, worked with the T2 bacteriophage, a virus that infects the bacterium Escherichia coli, consisting only of a protein coat surrounding a DNA core. They grew one batch of phages in a medium containing radioactive phosphorus (32P), which gets incorporated into DNA (since DNA, but not protein, contains phosphorus), and another batch in a medium with radioactive sulphur (35S), which gets incorporated into protein (since protein, but not DNA, contains sulphur amino acids). After allowing each labelled phage batch to infect separate E. coli cultures, they used a blender to shear off the empty phage coats from the bacterial cell surfaces and centrifuged the mixture to separate the coats (in the supernatant) from the infected bacterial cells (in the pellet). They found that the 32P (DNA) label was mostly found inside the bacterial cells, wh …