Explain how scientists showed that viruses hijacked cells with their DNA or RNA and not with their protein.

Two scientists Alfred Hershey and Martha Chase in 1952 did
a famous experiment to prove whether the protein coat, or the viral DNA was responsible
for hijacking a host cell's reproductive machinery, producing more viruses. Since
protein contains sulfur, some radioactive sulfur was put into one batch of T2 virus and
its host cell E.Coli bacteria. Since DNA contains phosphorus, radioactive phosphorus was
placed in a second batch of T2 virus with E.Coli. Depending on which one the bacteria
cell(host) incorporated, would determine which part of the virus was taking over the
cell's reproductive equipment. As it turned out, the phosphorus showed up inside the
bacteria cell therefore, it is DNA that a virus injects into a host cell, which in turn,
directs the host into replicating more viruses.