Explore how resistant bacterial variants survive antibiotic selection, reproduce and become common as overuse drives multi-resistant populations in IB Biology SL C3.2.14.
Syllabus
First assessment 2025
Course
Biology SL
Level
SL
Exam points
Explain how mutations or plasmids can introduce heritable antibiotic resistance into a bacterial population.
Explain how antibiotic use, overuse or incomplete courses select for resistance: susceptible bacteria die while resistant variants survive, reproduce and become more common.
Interpret resistance data by comparing strains and identifying resistance to multiple antibiotics.
Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis.
Describe the risk to the human population of indiscriminate use of antibiotics.
a
antibiotics block bacterial processes;
b
example of bacterial process, e.g. cell wall formation;
c
variations exist naturally in a population / some are naturally resistant to the antibiotic;
d
bacteria that are not resistant to this antibiotic will die / only resistant will survive (when antibiotic given);
e
this characteristic could be passed to next generation;
f
(natural selection) leads to changes in the proportions/frequency in the population;
g
human population will be exposed to antibiotic resistant bacteria and will not have antibiotic to kill them;
h
(antibiotic resistant bacteria) may pass resistance to other bacteria species/types by means of plasmids (so other bacteria species turn resistant too);