Explain why a person who smokes cigarettes and has a diet high in saturated fat is at greater risk of developing cardiovascular disease than a non-smoker with a healthy diet.

Model answer (4 marks)

Examiner tips

• Use the exact terms ‘plaques’, ‘atherosclerosis’, ‘narrowed arteries’, ‘blood pressure’ and ‘blood clots’.
• Show the causal chain: build‑up of plaques → narrowed arteries → reduced oxygen → heart attack.
• Mention the extra risk from smoking’s effect on blood pressure and clotting.
• Keep each point short and to the point to fit the 4 marks.

Common mistakes

• Mixing up ‘atherosclerosis’ with ‘hypertension’ or ‘stroke’ as the cause rather than the effect.
• Using vague phrases like ‘bad habits’ instead of specific mechanisms such as ‘plaque build‑up’ or ‘clot formation’.
• Leaving out the link between narrowed arteries and reduced oxygen supply to the heart.