3.32 understand that resistance to antibiotics can increase in bacterial populations, and appreciate how such an increase can lean to infections being difficult to control

Bacteria can develop mutations too, this changes the characteristics and some bacteria become more resistant to particular antibiotics. This means they have an increased chance of survival, so it lives longer and reproduces producing lots of bacterium that are resistant to that particular antibiotic. This is just natural selection.

This poses a problem for people who become infected with the mutated bacteria as the bacteria will not be killed off by the antibiotic supplied, that or a new antibiotic will need to be found which takes a long time.