OCR A-Level Geography H481
Coastal Landscapes
Glaciated Landscapes
Dryland Landscapes
Earth’s Life Support Systems
Changing Spaces; Making Places
Trade in the Contemporary World
Global Migration
Human Rights
Power and Borders
Climate Change
Disease Dilemmas
Exploring Oceans
Future of Food
Hazardous Earth
Geographical Skills
Disease Dilemmas
Mosquitoes, vectors and the seasonal rhythm of outbreaks
- 3 things to know
- Component 03
Overview
Recall questions on vectors and mosquito ecology, Aedes aegypti and dengue in tropical cities, the tsetse fly and sleeping sickness, ticks and Lyme disease, malaria seasons in the Sahel and the Congo Basin, monsoon rains in South Asia, winter influenza, cholera's two peaks in Bangladesh, drought and water storage, and using transmission seasons.
What you need to know
Answer each one before you reveal it.
Why does the pattern of malaria in the Sahel differ from that in the Congo Basin?
Which mosquito transmits dengue, and where does it breed?
Questions from this subtopic
Each one with the model answer underneath.
- 1
Define the term vector as it is used in the study of disease.
Model answer
A vector is an organism, usually an insect or other arthropod, that carries a pathogen from one host to another without becoming ill itself.
- 2
Why do mosquito populations peak in warm, humid places close to water?
Model answer
Warmth speeds up the larval and adult life cycle, humidity keeps adults alive for longer, and nearby standing water supplies the breeding sites, so all three conditions together allow numbers to build rapidly.
- 3
Which mosquito transmits dengue, and where does it breed?
Model answer
Aedes aegypti, which breeds in small collections of clean water around homes, such as water jars, tyres, gutters and plant pots.
- 4
Explain why urbanisation in the tropics has increased dengue.
Model answer
Dense cities give Aedes mosquitoes plentiful artificial breeding containers, intermittent piped water forces households to store water, and huge numbers of people live within the mosquito's short flight range.
- 5
Name the vector of sleeping sickness in Africa.
Model answer
The tsetse fly.
- 6
Which vector transmits Lyme disease in Europe?
Model answer
The tick Ixodes ricinus, often called the sheep tick.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Disease Dilemmas, on a schedule.
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