Question 18M.2.SL.TZ2.b
| Date | May 2018 | Marks available | [Maximum mark: 4] | Reference code | 18M.2.SL.TZ2.b |
| Level | SL | Paper | 2 | Time zone | TZ2 |
| Command term | Describe | Question number | b | Adapted from | N/A |
Although simple in structure, bacteria as a group show a wide range of diversity.
Describe the evolution of antibiotic resistance in bacteria.
[4]
a. problem results from excessive use of antibiotics by doctors/veterinarians/in livestock
OR
low antibiotic doses taken by patients (not finishing treatment)
b. natural variation exists in any population of bacteria making some resistant to a specific antibiotic
c. variation arises from mutation
OR
antibiotic resistance can be transferred between bacteria by plasmids
d. antibiotic kills all bacteria except those that are resistant
e. resistant bacteria survive, reproduce and pass on resistance to offspring
f. soon population is made of mainly antibiotic resistant bacteria
g. this is an example of natural selection «increasing frequency of characteristics that make individuals better adapted to environment»
