CAIE A Level Biology 9700 · Infectious diseases
In a rural village, an outbreak of cholera occurred after heavy flooding contaminated the main water source with sewage. The local health authority responded by distributing water purification tablets and installing handwashing stations.
Explain how cholera is transmitted and why providing clean water is an effective measure to control its spread.
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.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.