AQA GCSE Combined Science: Trilogy Biology Paper 1 (Higher), 2024: Question 7

6 marks · High Demand difficulty · Extended Answer

Explain the causes and symptoms of angina and how GTN reduces its symptoms.

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Question

Question text

07 Angina is a condition many people get as coronary heart disease (CHD) develops.

Angina can cause chest pain and tiredness.

People with angina are sometimes treated with a drug called GTN.

GTN widens the coronary arteries.

Explain:

• the causes and symptoms of angina

• how GTN reduces the symptoms of angina.

[6 marks]

Mark scheme

Show the mark scheme

Question 7

AO /

Question Answers Mark

Spec. Ref

07 Level 3: Relevant points (factors / effects) are identified, given in 5‒6 AO3

detail and logically linked to form a clear account.

Level 2: Relevant points (factors / effects) are identified and there 3‒4 AO3

are attempts at logical linking. The resulting account is not fully

clear.

Level 1: Points are identified and stated simply, but their relevance 1‒2 AO2

is not clear and there is no attempt at logical linking.

No relevant content 0 4.2.2.4

4.2.2.6

Indicative content 4.4.2.1

4.4.2.2

causes of angina / CHD:

• high cholesterol / fat (in blood / diet), obesity

• a lack of exercise

• smoking / alcohol

• increasing age

• a family history of atherosclerosis or heart problems

explanation of symptoms:

• fatty deposits in coronary arteries

• narrowing of the coronary arteries

• reduced blood / oxygen / glucose to the heart (muscle / tissue /

cells)

• reduced blood / oxygen / glucose to the body

• less oxygen / glucose for respiration

• less energy released

• (more) anaerobic respiration

• lactic acid formed

• muscle fatigue

treatment using GTN:

• more blood to the heart (muscle / tissue / cells)

• more oxygen / glucose to the heart (muscle / tissue / cells)

• increased (aerobic) respiration

For Level 1 explanation(s) of the symptoms of angina or the

treatment using GTN must be included

For Level 3 explanations must include the causes of angina,

explanations of the symptoms of angina and treatment using GTN

Total Question 7 6

How to answer it

Angina, CHD and GTN

What this question tests

This question tests your understanding of how coronary heart disease develops, what causes angina, why angina causes symptoms such as chest pain and tiredness, and how GTN helps by widening the coronary arteries so more blood, oxygen and glucose reach the heart muscle.

Question overview

This is a 6-mark extended response. To reach the top level, your answer must do all three of these:

state causes/risk factors of angina/CHD
explain the symptoms of angina
explain how GTN reduces the symptoms

Mark scheme insight: Level 3 (5–6 marks) needs relevant points in detail and logically linked together. That means you should write in a chain, not as isolated facts.

Part (a) 6-mark explanation

Explain the causes and symptoms of angina, and how GTN reduces the symptoms

✅ Correct answers

Angina happens when coronary arteries become narrowed because of fatty deposits (atherosclerosis).
Risk factors include high cholesterol / high fat diet, obesity, lack of exercise, smoking, alcohol, increasing age and family history.
Narrowed coronary arteries mean less blood reaches the heart muscle.
So the heart muscle gets less oxygen and glucose.
This means there is less aerobic respiration and less energy released.
The heart muscle may carry out more anaerobic respiration, causing lactic acid to build up.
This leads to chest pain and muscle fatigue / tiredness.
GTN widens the coronary arteries.
This allows more blood, oxygen and glucose to reach the heart muscle.
So aerobic respiration increases and the symptoms are reduced.

💡 Key knowledge

Angina is not the same as a heart attack. It is pain caused by reduced blood flow to the heart muscle.
Coronary arteries supply the heart muscle with blood.
Atherosclerosis means fatty deposits build up in arteries.
The heart needs oxygen and glucose for respiration.
If oxygen supply falls, cells cannot carry out enough aerobic respiration.

🧠 Exam technique

For 6-mark biology explanations, write as a clear chain of cause and effect.
Use linking words such as because, therefore, so, and this means.
Do not just list risk factors. You must also explain how they lead to symptoms and how GTN helps.
Include the words coronary arteries, oxygen, glucose, respiration, and heart muscle to show precise science.

❌ Common errors

Saying GTN cures CHD. It does not cure it; it reduces symptoms by widening arteries.
Only naming symptoms such as chest pain and tiredness without explaining why they happen.
Forgetting to mention causes/risk factors — this would stop you reaching Level 3.
Saying less oxygen reaches the lungs instead of the heart muscle.
Not linking reduced blood flow to less respiration, less energy and pain/fatigue.

Full-mark model answer

Angina is caused when fatty deposits build up in the coronary arteries, narrowing them. This is more likely in people with risk factors such as a high-fat or high-cholesterol diet, obesity, lack of exercise, smoking, alcohol, increasing age or a family history of heart disease.

The narrowed coronary arteries reduce the blood flow to the heart muscle, so the heart receives less oxygen and glucose. This means there is less aerobic respiration, so less energy is released. The heart muscle may also carry out more anaerobic respiration, causing lactic acid to build up. This leads to chest pain and tiredness or muscle fatigue.

GTN widens the coronary arteries, so more blood flows to the heart muscle. This brings more oxygen and glucose, allowing more aerobic respiration and reducing the symptoms of angina.

Why this scores highly: it covers causes, symptom explanation, and GTN treatment, and the ideas are logically linked in the correct order.

How marks are awarded

Level 1: 1–2 marks

Simple points are stated, but there is little or no linking.

Example: “Angina causes chest pain. GTN widens arteries.”

Level 2: 3–4 marks

Relevant points are included and there is some attempt to explain.

Example: “Fatty deposits narrow coronary arteries so less oxygen reaches the heart, causing chest pain. GTN widens the arteries.”

Level 3: 5–6 marks

A clear, detailed, logically linked explanation covering all parts of the question.

To reach this level, you must include causes, symptoms explained, and how GTN reduces symptoms.

Best structure to use in the exam

🧠 A simple 3-step plan

Cause: Describe fatty deposits and narrowing of coronary arteries, plus at least one risk factor.
Symptoms: Explain less blood → less oxygen/glucose → less respiration/energy → pain and tiredness.
Treatment: Explain GTN widens arteries → more blood/oxygen/glucose → more aerobic respiration → symptoms reduced.

Rapid recall

💡 Key words to include

fatty deposits
coronary arteries
narrowing
reduced blood flow
oxygen and glucose
aerobic respiration
less energy released
anaerobic respiration
lactic acid
GTN widens arteries

❌ Last-minute pitfalls

Do not stop after naming lifestyle factors.
Do not forget that the heart itself is a muscle needing oxygen and glucose.
Do not just say “GTN helps blood flow” — say why that reduces symptoms.

Examiner-style commentary

What separated stronger answers?

Top answers gave a linked story from risk factor to artery narrowing to reduced respiration to symptoms to treatment.
Weaker answers often gave only general statements like “blood can’t get through properly” without mentioning oxygen, glucose or respiration.
Some students lost marks by discussing only GTN or only causes of CHD. This question required both plus the symptoms.
Using precise biological language such as coronary arteries, heart muscle and aerobic respiration made answers clearer and stronger.

Topics

Biology · B5: Homeostasis and Response · B4: Bioenergetics

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Biology Paper 1 (Higher), 2024. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.