Question

The Hershey Chase experiment using radioactively labeled bacteriophage to infect bacteria proved that DNA was the genetic material. If you were reviewing those experimental results, which of the following would provide evidence that DNA was the genetic material? Select all that would apply.

a) The DNA was localized in the cytoplasm of the bacterial cell, which is the same site that the bacterial chromosome is located.

b) Radioactively labeled viral proteins were only found outside the cell and the viral infection proceeded normally

c) Radioactively labeled viral DNA was localized inside the cell where the new viral genomes and proteins are synthesized

d) After the phage had attached to the bacterial cells, the removal of all of the viral proteins from the bacterial cell surface did not prevent the viruses from infecting the bacteria

Answer 1

a) The DNA was localized in the cytoplasm of the bacterial cell, which is the same site that the bacterial chromosome is located. This is not evidence this is an information.

b) Radioactively labeled viral proteins were only found outside the cell and the viral infection proceeded normally. This is correct as proteins are not the genetic material so they remained outside the cells.

c) Radioactively labeled viral DNA was localized inside the cell where the new viral genomes and proteins are synthesized. This is correct as DNA was inside the cells and was helping in replication is the virus.

d) After the phage had attached to the bacterial cells, the removal of all of the viral proteins from the bacterial cell surface did not prevent the viruses from infecting the bacteria.

Viral proteins were removed from bacteriophage and still it was able to cause disease.

So, b, c, d are the evidences of the experiment.

A is correct but it is not experimental evidence.