Overview
What you’ll learn
- Define health as physical and mental well-being, not merely the absence of disease.
- Give the four classic examples of diseases interacting.
- Name risk factors with proven causal mechanisms and distinguish them from unproven links.
- Explain the effects of diet, alcohol, smoking and exercise on specific diseases, including unborn babies.
- Read scatter diagrams, frequency tables and incidence graphs — and say when a correlation is not a cause.
- Compare benign and malignant tumours, including how secondary tumours form.
- Discuss the human and financial costs of non-communicable disease at every scale.
Specification checklist (AQA 8461 · Edexcel 1BI0 · OCR Gateway J247)
Statements are paraphrased from the shared DfE subject content and grouped by tier. Foundation content is studied by every student; Higher statements are examined on Higher-tier papers only, and statements badged Biology only are examined in separate (triple) Biology, not Combined Science. QuizQuip is not affiliated with AQA, Pearson Edexcel or OCR.
Foundation — every student
- 5.1Describe health as the state of physical and mental well-being, and diseases — both communicable and non-communicable — as major causes of ill health; other factors including diet, stress and life situations affect both physical and mental health.
- 5.2Describe how different types of disease may interact: immune-system defects raise the risk of infectious diseases; viruses living in cells can trigger cancers; immune reactions to pathogens can trigger allergies such as skin rashes and asthma; severe physical ill health can lead to depression and other mental illness.
- 5.3Describe risk factors as aspects of a person’s lifestyle, or substances in the body or environment, that are linked to an increased rate of a disease; explain that a causal mechanism has been proven for some risk factors but not for others.
- 5.4Explain the effects of diet, smoking and exercise on cardiovascular disease; obesity as a risk factor for type 2 diabetes; alcohol on the liver and brain function; smoking on lung disease and lung cancer; smoking and alcohol on unborn babies; and carcinogens, including ionising radiation, as risk factors in cancer.
- 5.5Discuss the human and financial cost of non-communicable diseases to an individual, a local community, a nation and globally.
- 5.6Translate disease-incidence information between graphical and numerical forms; construct and interpret frequency tables, bar charts and histograms; use scatter diagrams to identify correlations between two variables; and understand the principles of sampling as applied to epidemiological data.
- 5.7Describe cancer as the result of changes in cells that lead to uncontrolled growth and division; describe benign tumours as growths contained in one area, usually within a membrane, that do not invade other parts of the body.
- 5.8Describe malignant tumour cells as cancers: they invade neighbouring tissues and spread through the blood to form secondary tumours elsewhere in the body; and describe lifestyle and genetic risk factors for various types of cancer.
Key points
- 1Health = physical + mental well-being; diseases (communicable and non-communicable) are major causes of ill health, but so are diet, stress and life situations.
- 2Diseases interact: immune defects → more infections · viruses can trigger cancer · immune reactions → allergies (rashes, asthma) · severe physical illness → depression.
- 3Risk factors are lifestyle aspects or substances in the body/environment linked to higher disease rates — proven causal mechanism for some, not all.
- 4Proven pairs to quote: diet/smoking/exercise → cardiovascular disease · obesity → type 2 diabetes · alcohol → liver and brain · smoking → lung disease and lung cancer · smoking and alcohol → unborn babies · carcinogens and ionising radiation → cancer.
- 5Non-communicable disease costs individuals, communities, nations and the world — in suffering and money (treatment, lost work, carers).
- 6Correlation is not causation — a scatter diagram can show a link that a third factor explains; epidemiology uses careful sampling to test the link.
- 7Cancer = changes in cells causing uncontrolled growth and division; benign tumours stay put in a membrane; malign tumours invade, spread in the blood and form secondary tumours.
- 8Cancer risk factors: lifestyle (smoking, alcohol, diet, ionising radiation) and genetic (inherited predisposition).
Notes · 1 of 4
Health and interacting diseases
Well-being is two-dimensional — and diseases rarely come alone.
Health is the state of physical and mental well-being — not just “not being ill”. Diseases, both communicable (catchable, caused by pathogens) and non-communicable (not caught, often long-term), are major causes of ill health, but so are diet, stress and life situations. Someone can have no diagnosed disease and still be in poor health; someone with a managed condition can still be well. Exams reward this two-dimensional definition.
| Interaction | Example in words |
|---|---|
| Immune defects → infections | A person whose immune system is weakened (for example by another condition) is more likely to catch infectious diseases |
| Viruses → cancer | Some viruses live inside cells and can trigger changes that lead to cancer |
| Pathogen → allergy | An immune reaction originally aimed at a pathogen can misfire as an allergy, causing skin rashes or asthma |
| Physical illness → mental illness | Severe physical ill health can lead to depression and other mental illnesses — body and mind pull on each other |
Notes · 2 of 4
Risk factors and their effects
Lifestyle and environment write part of your medical future — some lines in ink.
A risk factor is something linked to an increased rate of a disease. It can be an aspect of lifestyle (smoking, diet, exercise, alcohol) or a substance in the body or environment (pollutants, ionising radiation, carcinogens). Crucially, a causal mechanism has been proven for some risk factors but not for others — and being able to say which is which is a named exam skill.
| Risk factor | Disease or effect |
|---|---|
| Diet (high fat/salt), smoking, lack of exercise | Cardiovascular disease |
| Obesity | Type 2 diabetes |
| Alcohol | Liver disease (cirrhosis) and impaired brain function |
| Smoking | Lung disease, lung cancer and cardiovascular disease |
| Smoking and alcohol during pregnancy | Harm to the unborn baby’s development |
| Carcinogens, including ionising radiation | Cancer |
Many diseases are caused by the interaction of several factors, not one: a person’s heart-disease risk combines diet, smoking, exercise, genes and age. And the costs run wide. Non-communicable diseases cost the individual suffering and reduced quality of life, the family caring time and income, the community and nation treatment bills and lost productivity, and the world billions in health spending — the human and financial cost argument examiners ask you to rehearse.
Notes · 3 of 4
Correlation, causation and epidemiology
Reading the graphs — and knowing when a link is not a cause.
Epidemiology studies who gets which disease, where and when, using samples of the population. The toolset: frequency tables and bar charts for counts, histograms for grouped continuous data, and scatter diagrams for asking whether two variables move together. A scatter diagram with points rising together shows a positive correlation; falling together, a negative one; a shapeless cloud shows no correlation. But a correlation alone does not prove one variable causes the other — a third factor could drive both, or the link could be coincidence. A causal mechanism — a tested explanation of how one thing brings about the other — is what upgrades a correlation to a cause.
Notes · 4 of 4
Cancer: benign and malignant tumours
When cell division ignores its brakes — and the word that separates a lump from a cancer.
Cancer is the result of changes in cells that lead to uncontrolled growth and division. The runaway cells form a tumour. Two kinds matter. A benign tumour is a growth of abnormal cells contained in one area, usually within a membrane — it does not invade other parts of the body, though it can cause problems by pressing on organs. A malignant tumour is what the word cancer means: its cells invade neighbouring tissues and can spread to different parts of the body in the blood, where they set up secondary tumours. The spread — not the size — is what makes malignant disease dangerous.
| Feature | Benign tumour | Malignant tumour (cancer) |
|---|---|---|
| Spread | Contained in one area, usually in a membrane | Invades neighbouring tissues |
| Secondary tumours | None | Cells travel in the blood and form secondaries elsewhere |
| Danger | From pressure on organs; often removable | Life-threatening; needs aggressive treatment |
| Growth rate | Can be slow | Often rapid and uncontrolled |
Cancer risk factors come in two flavours: lifestyle factors — smoking (lung cancer), alcohol, diet, obesity, and exposure to carcinogens such as ionising radiation — and genetic factors, where inherited variants raise the chance of certain cancers. Most cancers need several changes to accumulate, which is why risk rises with age and why two people with the same exposure can have different outcomes.
Revise
Key terms
The words examiners expect you to use precisely.
- Health
- The state of physical and mental well-being.
- Communicable disease
- A disease caused by pathogens that can spread between people.
- Non-communicable disease
- A long-term disease that cannot be caught, such as coronary heart disease or type 2 diabetes.
- Risk factor
- A lifestyle aspect or body/environment substance linked to an increased rate of a disease.
- Causal mechanism
- A proven explanation of how one factor brings about a disease.
- Correlation
- A statistical link where two variables change together; it does not prove cause.
Show 6 more key termsShow fewer key terms
- Epidemiology
- The study of disease patterns in populations, using samples of data.
- Carcinogen
- A substance (including ionising radiation) that raises the risk of cancer.
- Tumour
- A growth of cells resulting from uncontrolled cell division.
- Benign tumour
- A tumour contained in one area, usually within a membrane, that does not invade other tissues.
- Malignant tumour
- A cancer: it invades neighbouring tissues and can spread in the blood to form secondary tumours.
- Secondary tumour
- A new tumour formed elsewhere in the body by malignant cells travelling in the blood.
Revise
Common mistakes
Where students most often lose marks in this chapter — and what to do instead.
Mistake: Defining health as "not having a disease".
Health is broader — it includes mental well-being.
Instead: Health is the state of physical and mental well-being.
Mistake: Treating every correlation as a cause.
A third factor may drive both variables.
Instead: A causal mechanism must be proven before a risk factor is accepted as a cause.
Show 10 more mistakesShow fewer mistakes
Mistake: Saying benign tumours are harmless in every way.
They can still press on organs and cause damage.
Instead: Benign tumours do not invade or spread, but pressure effects can be serious.
Mistake: Saying malignant cells spread through the nerves.
The route named in the spec is the blood.
Instead: Malignant cells travel in the blood and form secondary tumours.
Mistake: Writing "cancer is infectious".
Cancer itself is not caught from another person.
Instead: Some viruses living in cells can trigger cancer, but the cancer is not contagious.
Mistake: Claiming obesity causes lung cancer directly.
The proven obesity link is with type 2 diabetes.
Instead: Match the factor to its proven disease: obesity → type 2 diabetes; smoking → lung disease and lung cancer.
Mistake: Saying smoking only harms the smoker.
Smoking in pregnancy harms the unborn baby, and passive smoke affects others.
Instead: Smoking and alcohol both damage unborn babies’ development.
Mistake: Saying alcohol only damages the liver.
Brain function is affected too.
Instead: Alcohol harms the liver and impairs brain function.
Mistake: Treating non-communicable disease as free because it is not caught.
The financial costs are enormous at every scale.
Instead: Treatment costs, lost productivity and carer burdens make NCDs a national and global expense.
Mistake: Assuming a scatter diagram proves one variable caused the other.
Scatter diagrams only show correlation.
Instead: Correlation suggests a link; a proven causal mechanism establishes cause.
Mistake: Saying carcinogens cause all cancers single-handedly.
Most cancers arise from an interaction of several risk factors, including genetic ones.
Instead: Lifestyle and genetic risk factors combine; risk rises with the number of factors.
Mistake: Ignoring sampling in epidemiological claims.
A biased sample wrecks the conclusion.
Instead: Epidemiology needs representative samples before its rates mean anything.
Check yourself
Quick quiz
30 questions with instant explanations. About 5 minutes.
Question 1 of 3
- Question 1: current question
- Question 2: not answered
- Question 3: not answered
Define health
Health is best defined as
Ready for more practice on Health & cancer?
Generate a fresh 5-question adaptive drill grounded in this chapter’s GCSE key points. Free with your study account.
Practise
Topical questions
18 exam-style questions with model answers and mark schemes.
A set of structured and calculation questions matched to this chapter, in three tiers, each with a model answer, mark scheme and examiner tip. Higher-tier and Biology-only questions are tagged.
Practise topical questionsExam practice
Practice paper
A 30-mark paper in the style of a GCSE paper, with a separate mark scheme. Give yourself 40 min.
Question paper
Chapter 5 Practice Paper
30 marks · 40 min · 5 pages
10 multiple-choice questions and structured questions with answer lines. Chapter 5: health and interacting diseases, risk factors and their proven effects, the human and financial cost of non-communicable disease, correlation versus causation with epidemiological data, and benign versus malignant tumours.
Mark scheme
PROChapter 5 Practice Paper — mark scheme
Answers · Marking points · 3 pages
Model answers with a mark for each creditworthy point — for marking at home or in class.
How is this chapter examined?
Paper 1
1 h 45 · 100 marks
Topics 1–4: cell biology, organisation, infection and response, bioenergetics (chapters 1–10)
Paper 2
1 h 45 · 100 marks
Topics 5–7: homeostasis and response, inheritance variation and evolution, ecology (chapters 11–18)
Tiers
Foundation (grades 1–5) · Higher (grades 4–9)
Higher assumes all Foundation content; ten required practicals are examined on the papers
Want a full paper? Try the Paper 1-style (Foundation), Paper 1-style (Higher), Paper 2-style (Foundation), Paper 2-style (Higher), Required practicals practice sets.
Questions
Frequently asked questions
How do I remember the four disease interactions?
Four pairs: weak immunity → more infections; virus in cells → cancer; pathogen → allergy; body illness → depression. If you can quote two with mechanisms, most questions are covered.
What is the one-line rule for correlation questions?
Describe the correlation, then say a third factor could explain it, then state that a proven causal mechanism is what turns a link into a cause. Three sentences, most of the marks.
Why does the spec distinguish proven from unproven risk factors?
Because honesty matters in medicine: some links (smoking → lung cancer) have demonstrated mechanisms, while others are only statistical patterns. Exams want you to know the difference.
What separates a benign tumour from a malignant one in one sentence?
Benign stays put behind a membrane; malignant invades neighbouring tissue and sends cells through the blood to form secondary tumours.
How should I structure a costs-of-disease answer?
Layer the scales: individual suffering → family and carer burden → community and national treatment bills and lost work → global costs. Two layers with examples is usually enough.
Does QuizQuip have any connection to the exam boards?
No. AQA, Pearson Edexcel and OCR are named only to identify the specifications this content supports. QuizQuip is not affiliated with, endorsed by, or connected to AQA, Pearson Edexcel or OCR, and no past-paper or specimen material is reproduced.
Up next
Chapter 6: Plant tissues and transport