Genetics: Analysis and Principles 5th Edition by Robert Brooker

Exercise 29

With regard to the experiment of Figure 9.5, answer the following:
a. Provide possible explanations why some of the DNA is in the supernatant
b. Plot the results if the radioactivity in the pellet, rather than in the supernatant, had been measured
c. Why were 32 P and 35 S chosen as radioisotopes to label the phages
D. List possible reasons why less than 100% of the phage protein was removed from the bacterial cells during the shearing process.FIGURE 9.5 Evidence that DNA is the genetic material of T2 bacteriophage. Starting materials: The starting materials were E. coli cells and two preparations of radiolabeled T2 phage. One phage preparation had phage proteins labeled with 35 S, and the other preparation had phage DNA labeled with 32 P.