Give an account of Hershey and Chase experiment. What did it conclusively prove?If both $DNA$ and proteins contained phosphorus and sulphur do you think the result would have been the same ?

Which property of $DNA$ double helix led Watson and Crick to hypothesise semiconservative mode of $DNA$ replication? Explain.

Who revealed biochemical nature of the transforming principle ? How was it done ?

Chemically $DNA$ differs from $RNA$ in having

Recall the experiments done by Frederick Griffith, Avery, MacLeod and McCarty, where $DNA$ was speculated to be the genetic material. If $RNA$, instead of $DNA$ was the genetic material, would the heat killed strain of Pneumococcus have transformed the $R\,-$ strain into virulent strain ? Explain.