Selection of resistant strains of bacteria within months of starting a…

Question

Selection of resistant strains of bacteria within months of starting antibiotic treatment is presented in the chapter as evidence that:

Accepted Answer

C. {'text': 'Selection acts on pre-existing variation, and evolution is fast in short-lived microbes', 'label': 'C'}

Microbes divide fast, so any pre-existing advantageous variant (here, resistance) is amplified rapidly when an antibiotic kills off susceptible cells. The chapter uses this to argue that evolution operates over months in microbes, that variation is heritable and that selection (not directed mutation) acts on existing variation.

Answer

{'text': 'Antibiotic exposure causes targeted mutations specifically conferring resistance', 'label': 'A'}

Answer

{'text': 'Evolution is a directed, purposeful process aimed at organism survival', 'label': 'B'}

Answer

{'text': "Resistance is acquired during a bacterium's lifetime and inherited Lamarckianly", 'label': 'D'}