Question

In 1928 Alexander Fleming discovered penicillin was an effective antibiotic for Staphylococcus aureus bacterial infections.  Over the years, penicillin continued to cure millions of people of potentially deadly microbes; however, penicillin is not as effective as it has been in the past.   How do bacteria become resistant to antibiotics over time?Group of answer choicesA) Bacteria can alter their genetic make-up as a response to exposure to certain types of antibiotics producing antibiotic-resistant bacteria.B) Bacteria have a very long generation time which allows the bacteria an opportunity to alter their genetic make-up in a way that minimizes the effect of antibiotics. Consecutive generations produce more bacteria with altered genetic makeup allowing for survival and antibiotic resistance.C) Bacteria have a very fast generation time which allows for favorable genetic mutations to occur that can prevent antibiotics from killing the microbes. Consecutive generations produce more bacteria with mutations allowing for survival and antibiotic resistance.D) Bacterial DNA cannot mutate to form a resistance to certain types of antibiotics.

Answer 1

Resistance to antibiotics develops because of natural selection, although most of the bacteria were killed by antibiotics, some had mutations that allowed them to survive, and as bacteria have fast generation times, then the next generation inherits the mutations that allow them to resist antibiotics.

This means C (Bacteria have a very fast generation time which allows for favorable genetic mutations to occur that can prevent antibiotics from killing the microbes. Consecutive generations produce more bacteria with mutations allowing for survival and antibiotic resistance.) would be the right answer.