A)

Question

In 1952, Alfred Hershey and Martha Chase conducted an experiment about bacteriophage reproduction. They inserted a phosphorous isotope (^ 10 P) into the bacteriophages DNA, and a sulfur isotope (^ 35 s) into a protein in the bacteriophages capsids. Hershey and Chase then infected bacteria with the bacteriophages After infection, they put the bacteria in a blender to separate the cells from the extracellular matter They measured the percentage of isotopes that remained in the extracellular matter. The results are in the graph below

100-

90-

80-

TO-

60

30-

40

30-

20-

10-

0

12

extracellular S

Use the passage to answer the question

Which statement about bacteriophage reproduction is supported by the results of this study?

(1 point)

The sulfur isotopes entered the bacteria because they were attached to the bacteriophages genetic material

The phosphorous isotopes entered the bacteria because they were attached to the bacteriophages genetic material

extracellular P

867

running time in blender (min)

The sulfur isotopes remained outside of the bacteria because they were attached in the bacteriophages genetic material

The phosphorous isotopes remained outside of the bacteria because they were attached to the bacteriophages genetic material

percent of total isotope

Answer 1

The statement "The phosphorous isotopes entered the bacteria because they were attached to the bacteriophages genetic material" is supported by the results of this study. This is because the phosphorous isotope (^10P) that was inserted into the bacteriophages DNA was found inside the bacteria after infection, as shown by the graph. Conversely, the sulfur isotope (^35S) that was inserted into the protein in the bacteriophages capsids remained outside of the bacteria.