CAIE A Level Biology 9700 · Infectious diseases
A patient with a bacterial throat infection is prescribed a course of penicillin. After a few days, the infection has not improved. Laboratory tests show that the bacteria are resistant to penicillin.
(a) Describe how penicillin acts on bacteria to kill them. (b) Explain why antibiotics such as penicillin are not effective against viruses. (c) Discuss the consequences of antibiotic resistance and suggest steps that can be taken to reduce its impact.
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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