Question 1
State three ways in which the activity of the heart may be monitored.
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- ECG (1)
- pulse rate (1)
- listening to the sounds of the valves closing / using a stethoscope (1)
Question 2
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDescribe how the heart pumps blood out of the ventricles, including the action of the valves.
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- ventricles contract (1)
- atrioventricular valves close, stopping backflow into the atria (1)
- semilunar valves open (1)
- blood forced into the aorta and pulmonary artery (1)
- semilunar valves close when ventricles relax to prevent backflow (1)
- Max 4
Question 3
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanA student measured their heart rate at rest, after exercise and during recovery. (a) Calculate the percentage increase in heart rate from resting to after 2 minutes of running. [2] (b) Explain why heart rate increases during exercise. [3]
| Activity | Heart rate / beats per minute |
|---|---|
| Resting | 72 |
| After 2 minutes of running | 126 |
| 5 minutes after stopping | 84 |
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- (a) 126 − 72 = 54 (1)
- 54 ÷ 72 × 100 = 75% (1)
- (b) muscles respire faster / more aerobic respiration (1)
- need more oxygen and glucose (1)
- faster heart rate delivers these faster and removes carbon dioxide / lactic acid faster (1)
Question 4
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels mean(a) Describe coronary heart disease. [3] (b) State one risk factor for coronary heart disease that a person cannot change. [1]
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- (a) fatty deposits build up in the coronary arteries (1)
- which blocks / narrows the arteries so less blood flows (1)
- less oxygen / glucose reaches the heart muscle, (may cause) a heart attack (1)
- (b) genetic predisposition / age / sex (1) allow family history
Question 5
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDiscuss the roles of diet and exercise in reducing the risk of coronary heart disease.
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- diet low in saturated fat reduces fatty deposits (1)
- less salt / more fruit and vegetables helps healthy arteries and blood pressure (1)
- exercise strengthens the heart muscle / lowers blood pressure (1)
- exercise helps control body mass (1)
- other risk factors such as age, sex or genes cannot be changed (1)
- Max 4