You add an unknown phage to a mixture of F+ and F- cells of E. coli and plate out the bacteria. The bacterial colonies that grow are all F-. How can you explain this phenomenon?
A. The phage bound to a receptor on the sex pilus, and therefore only infected the F+ cells (leaving the F- cells alone).
B. The phage bound to a receptor on the F- cells, leaving only them alive and allowing the F+ cells to die off.
C. The phage integrated (lysogenized) the F- cells, giving them a selective advantage over the F+ cells.
D. F+ cells are uniquely susceptible to phage attack for unknown reasons.
A
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Fill in the blank(s) with the appropriate word(s).