AQA GCSE Biology Foundation (8461), Foundation tier · Organisation › Animal tissues, organs and organ systems
Practise Lifestyle and non-communicable diseases. 6 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
How risk factors such as diet, smoking, lack of exercise and alcohol affect the incidence of non-communicable diseases, why a correlation is not the same as causation, and the human and financial costs of these diseases. Expect scatter-graph data questions, 'explain' questions on particular risk factors and 'discuss' questions on costs.
Key facts
Risk factor = linked to an increased rate of a disease
Diet, smoking and lack of exercise → cardiovascular disease
Obesity → type 2 diabetes
Alcohol → liver disease and effects on brain function
Smoking → lung disease and lung cancer
Smoking and alcohol in pregnancy → harm to the unborn baby
Carcinogens (including ionising radiation) → cancer
Correlation does not prove causation: a causal mechanism is needed
Notes
Risk factors
A risk factor is linked to an increased rate of a disease. It can be an aspect of a person's lifestyle (e.g. smoking) or a substance in the person's body or environment (e.g. ionising radiation).
A risk factor increases the chance of getting a disease. It does not mean the person will definitely get it.
For some risk factors a causal mechanism has been proven, e.g. chemicals in tobacco smoke cause mutations that lead to lung cancer. For others only a correlation has been found so far.
Many diseases are caused by the interaction of a number of factors.
Lifestyle factors and their effects
Cardiovascular disease: a diet high in saturated fat raises blood cholesterol, and smoking damages blood vessels and raises blood pressure. Regular exercise lowers the risk.
Obesity is a major risk factor for type 2 diabetes.
Alcohol damages liver cells (leading to liver disease) and affects brain function; heavy drinking over a long time can permanently damage the brain.
Smoking causes lung diseases, such as bronchitis and emphysema, and lung cancer.
In pregnancy, smoking reduces the oxygen reaching the fetus, which can cause low birth weight and premature birth. Alcohol can damage the baby's brain and growth.
Carcinogens, including ionising radiation (e.g. X-rays and gamma rays), are risk factors for cancer.
Correlation, causation and costs
diagram
A scatter diagram can show a correlation, e.g. as the number of cigarettes smoked per day increases, the rate of lung cancer increases (a positive correlation).
A positive correlation. It shows a link, but on its own it does not prove cause.
A correlation does not prove that one factor causes the other: another factor could be responsible. Scientists need large, representative samples and a mechanism that explains the link.
Human cost: pain, suffering, reduced quality of life and early death, which also affect families.
Financial cost: to the individual (lost income), the community and nation (healthcare costs, lost working days) and globally, as these diseases become more common in many countries.
Don’t lose marks
Saying a risk factor 'causes' a disease. It increases the chance (rate) of the disease.
Saying a correlation proves that one thing causes another.
Mixing up the targets, e.g. saying alcohol damages the lungs.
Saying obesity is a risk factor for type 1 diabetes. It is a risk factor for type 2 diabetes.
Describing a graph with no numbers when the question says 'use data'.
More tips
Memory tricks
Link each factor to its target: smoking → lungs and heart; alcohol → liver and brain; obesity → type 2 diabetes; carcinogens → cancer; diet and exercise → heart and blood vessels.
Correlation is not causation: ice cream sales and sunburn both rise in summer, but ice cream does not cause sunburn.
Costs, 'Person, Place, Purse': the person and their family, the community and nation, and the money.
Exam technique
'Discuss' means give points about different aspects (human and financial; individual and national), not just one.
When describing a scatter diagram, name the type of correlation and quote values.
When asked whether data prove a cause, explain why not: other factors, sample size, the need for a mechanism.
Link lifestyle factors to specific biology, e.g. saturated fat → cholesterol → fatty material in arteries, not just 'unhealthy'.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 3
Define a risk factorA factor linked to an increased rate of a disease, such as part of a person's lifestyle or a substance in their body or environment.
Grade 4
Match risk factors to the diseases they affectDiet, smoking and lack of exercise → cardiovascular disease; obesity → type 2 diabetes; alcohol → liver and brain; smoking → lung disease and lung cancer; carcinogens → cancer.
Grade 5
Describe effects of smoking and alcohol in pregnancyBoth can harm the unborn baby, e.g. smoking can cause low birth weight and alcohol can damage the baby's brain development.
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
Lifestyle factors can affect the risk of developing some non-communicable diseases.
(a) What is meant by a risk factor for a disease?[1]
(b) Obesity is a risk factor for which disease? Tick (✓) one box.[1]
Malaria
Measles
Tuberculosis
Type 2 diabetes
(c) Name one organ that can be damaged by drinking too much alcohol.[1]
(d) Give one disease for which smoking is a risk factor.[1]
Show the answer and mark scheme
(a)
something that is linked to an increased rate / likelihood of the disease