Hershey and Chase conducted an experiment to check whether genetic material is made up of DNA or protein.
They crossed the marked and unmarked (radioactive phosphorus and sulfur) bacteria and found that the phages of infected bacteria infected the unmarked bacteria. It first attaches to the host bacteria surface and then entered into it where it replicates itself. With subsequent replication, the bacteria lyses and burst. In the later research by Hershey and chase, it was concluded that phages that entered the host bacteria were the proteins