1. The table shows the results of a blood test carried out on a patient who had suffered a heart attack. All units are arbitrary units.

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1 1. The table shows the results of a blood test carried out on a patient who had suffered a heart attack. All units are arbitrary units. Substance Concentrations in patient s blood Normal range Cholesterol Glucose 13.6 Less than 7 Aspartate transaminase Lactate dehydrogenase (a) (i) Explain the link between high blood cholesterol and heart attacks. (3) (ii) Explain why it is not possible to say that the high cholesterol concentration in the blood of this patient caused the heart attack. The Queen Katherine School 1

2 (b) Aspartate transaminase and lactate dehydrogenase are enzymes that are normally found inside muscle cells. Suggest why measurement of the concentration of these enzymes in the blood can be used to confirm that a person has had a heart attack. (Total 7 marks) The Queen Katherine School 2

3 2. The chart shows the risk of developing coronary heart disease during the next ten years in relation to a number of risk factors. WOMEN MEN non smoker smoker non smoker smoker Age Age Blood pressure/mm of mercury Age Age Age Plasma cholesterol concentration/mmol dm 3 Risk < 5% 5 10% 10 20% 20 40% > 40% The Queen Katherine School 3

4 (Adapted from Odyssey, the Glaxo Weilcome Journal of Innovation in Healthcare by permission of ExcerptaMedica.) (a) According to the chart, what are the characteristics of the people with the highest risk of developing coronary heart disease? (b) Explain the relationship between the risk of developing coronary heart disease and (i) plasma cholesterol; (ii) the sex of the person concerned (1) (c) Explain the limitations of using the chart as a method of prediction of the risk of developing coronary heart disease (3) (Total 8 marks) The Queen Katherine School 4

5 3. (a) Explain why atheroma may result in cardiovascular disease. (4) (b) Three of the risk factors associated with the development of cardiovascular disease are eating a diet high in saturated fat, eating excessive quantities of salt and smoking. Explain why these factors increase the risk of developing cardiovascular disease. (8) (Total 12 marks) The Queen Katherine School 5

6 4. Several risk factors influence the onset of coronary heart disease (CHD). These include a blood cholesterol level greater than 2.5 g dm 3 blood pressure greater than 25 kpa; smoking more than 20 cigarettes per day. The chart shows the effect of combining these three factors on the incidence of coronary heart disease Incidence of CHD per people Number of risk factors (a) Describe the effect on the incidence of coronary heart disease of increasing the number of risk factors The Queen Katherine School 6

7 (b) Explain how each of the following factors increases the risk of coronary heart disease. (i) high blood cholesterol level (ii) high blood pressure.... (iii) heavy smoking.... (10) (Total 12 marks) The Queen Katherine School 7

8 5. Atheromas can form in coronary arteries and produce a condition called angina. An angina sufferer experiences pains in the chest, usually during exercise. The pain is caused by a build-up of lactate in heart tissues. Sometimes an atheroma gets damaged and a blood clot forms which blocks the coronary artery. This causes myocardial infarction which can be fatal. Angina can be diagnosed from a type of X-ray called an angiogram. A small tube is inserted into an artery at the top of the leg and pushed up to the opening of the coronary artery. A special dye is injected into the artery and an X-ray is taken. (a) Explain the meaning of (i) atheroma;... (1) (ii) myocardial infarction.... (1) (b) Describe one way in which the lifestyle of a person could increase the risk of developing angina. (1) S (c) Suggest why angina sufferers experience a build-up of lactate during exercise. (3) (d) Suggest why it is necessary to inject a special dye before taking an angiogram. (1) (Total 7 marks) The Queen Katherine School 8

9 6. (a) The graph shows the risk of a 50-year-old male having a heart attack during the next ten years, in relation to several risk factors. 30 Smoker Maximum blood pressure 24 kpa Risk of heart attack / % 20 Non-smoker Maximum blood pressure 24 kpa Smoker Maximum blood pressure 16 kpa 10 Non-smoker Maximum blood pressure 16 kpa Plasma cholesterol concentration / mmol dm 3 Reproduced with permission from New Scientist magazine RBI Ltd (i) Describe what the graph shows about the effect of smoking on the risk of having a heart attack. (ii) Explain why an increase in plasma cholesterol concentration increases the risk of a heart attack. The Queen Katherine School 9

10 S (b) Cigarette smoke contains nicotine. Nicotine stimulates the sympathetic nervous system and increases the stickiness of blood platelets. Explain how these effects of nicotine increase the risk of cardiovascular disease. (4) (Total 8 marks) The Queen Katherine School 10

11 7. An increased concentration of cholesterol in the blood is one factor increasing the risk of myocardial infarction (heart attack). The graph shows the relationship between death from myocardial infarction and blood cholesterol concentration Number of deaths from myocardial infarction in 9000 a population per year Key Risk Deaths Risk of myocardial infarction Concentration of cholesterol in blood plasma / mg 100 cm 3 (a) (i) Describe how high concentrations of cholesterol in the blood can lead to disease of the blood vessels supplying the heart. (ii) Explain how disease of these blood vessels may lead to death from myocardial infarction. (3) (b) The number of deaths from myocardial infarction decreased at concentrations of cholesterol above 250 mg 100 cm 3 blood whereas the risk of myocardial infarction continued to rise. Suggest an explanation for this difference.. The Queen Katherine School 11

12 ... (Total 7 marks) The Queen Katherine School 12

1. Coronary heart disease is a major cause of death in the western world.

1. Coronary heart disease is a major cause of death in the western world. (a) The diagram shows an external view of a human heart with a blood clot in one of the main coronary arteries. (i) (ii) Shade,