Hi, can someone help me with these questions? I put only C for the first one because I thought that the viruses couldn't infect the bacteria, and for the second one I put B because but both were wrong.
1.) Hershey and Chase used radioactive 35S and 32P in experiments to provide evidence that DNA was the genetic material. These experiments pointed to DNA because: (choose all correct answers)
a.) Absence of 35S in progeny viruses indicated that labelled proteins had not been produced during the infection.
b.) Viruses that budded from the infected cells contained labeled DNA.
c.) Viral particles were not viable (couldn't infect bacterial cells) following treatment in the blender used for these experiments.
d.) 32P, but not 35S, entered the bacterial cells upon infection.
2.) You grow bacterial cells for several generations in a medium with fluorescently labeled pink dGTP as the only source of dGTP. After taking some of these cells for a control, you take another batch and transfer them to a growth medium that contains non-labeled dGTP. You grow the cells just long enough for them all to complete one round of DNA replication, and then you harvest the cells, break them open, and isolate the DNA. You then measure the amount of pink fluorescence in the control and experimental cells. Relative to the control cells that were grown in the labeled pink dGTP, how much pink fluorescence will you expect to see in the cells grown for one generation in unlabeled dGTP medium?
a.) 100%
b.) 75%
c.) 50%
d.) 25%
e.) 0%
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