A laboratory technician cultures a vancomycin-resistant strain of MRSA (methicillin-resistant Staphylococcus aureus) for 100 generations on agar media without antibiotics, selecting the largest colony on the plate (best growing) for passage (plating to grow on a new place) at each generation. Would you predict that the 100th generation would be more or less resistant to vancomycin? Justify your response and be sure to include the following information:
a. (2) Will mutations occur in these bacteria? Explain.
b. (2) What are the selective pressures exerted on these bacteria?
c. (2) Will the bacteria in the culture evolve? Explain.
d. (4) Answer the original question - Would you predict that the 100th generation would be more or less resistant to vancomycin? Justify your response.
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