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Superbugs: A Case of Natural Selection
During the Program
1.
What selective agent resulted in changes in beak shape in the finches on the Galapagos Islands?
2.
(a) Circle/highlight the statement which is not a part of Charles Darwin’s understanding of natural selection:
(i)
Offspring tend to resemble their parents
(ii) Characteristics are passed on from parents to offspring through genes
(iii) Over time, populations become better suited to their environments
(iv) Individuals in a population that are better suited to their environment are more likely to survive and
reproduce.
(b) Explain your answer to 2(a).
3.
What are the two main sources of genetic variation?
1.
2.
4.
In what 2 ways have populations of mosquitos adapted to the use of the pesticide DDT?
1.
2.
5.
Drug resistance shown by the malaria parasite or bacteria is genetically based.
(a) What does this mean?
(b) Why is this an important factor in natural selection?
6.
Prior to the development of antibiotics, humans still had some defence against bacterial infection. Explain.
7.
In the program, what is meant by the term “superbugs”?
8.
What factors have contributed to the rapid rise in antibiotic resistance in bacteria?
9.
Where would you expect higher levels of antibiotic resistance to occur, in a large city hospital or a country hospital?
Explain your answer.
10. What methods do hospitals use to control the spread of bacterial infection?
11. List one medical alternative to antibiotics which has been used to deal with bacterial infections.
12. Explain why doctors prescribing antibiotics for patients with colds are generally of little use.
13. Overuse of antibiotics is considered to be a major factor in the emergence of antibiotic resistant strains of bacteria.
What non-medical use of antibiotics has given rise to concern?
14. Would it be correct to say that the use of an antibiotic causes individual bacteria to become resistant? Explain your
answer.
15. Golden Staph and Enterococcus are different types of bacteria which can infect and cause serious illness in humans.
Explain how the use of the antibiotic vancomycin to treat infections with Golden Staph may have contributed to the
emergence of populations of Vancomycin resistant Enterococcus (VRE).
16. In a small group, complete the concept map below by adding arrowed lines between the concepts to show which are
linked. Compare your final map with those of other groups. Note: Only join those concepts which you consider to
be linked.
overuse of
antibiotics
patients’
expectations of
doctors
selection for
antibiotic
resistance
human disease
caused by
bacteria
treatment of
livestock with
antibiotics
antibiotics
development of
new antibiotics