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Antibiotic Resistance: Penicillin

APBIO-DKECIX

A new bacterial infection is spreading through a city. Doctors start prescribing penicillin, but they soon find that the bacteria is resistant to the antibiotic.

Testing reveals that a penicillin resistance gene is located on a plasmid that is increasing in the bacteria population through conjugation and selection due to the use of penicillin. Doctors start using rifampicin, another antibiotic that works through a different mechanism than penicillin.

Which of the following is MOST likely to occur in the bacteria population?

A

All bacteria without the penicillin resistance plasmid will be eliminated from the population by the use of rifampicin.

B

The penicillin resistance plasmid will be eliminated from the population in several generations due to lack of use.

C

The penicillin resistance plasmid will continue to increase in the population because it will protect against rifampicin.

D

The spread of the penicillin plasmid will slow, but it will remain in the population.