Question 1: Define coronary heart disease.

Answer: Coronary heart disease is a condition where the coronary arteries become narrowed or blocked, reducing blood flow to the heart muscle.

Question 2: Explain the main mechanism by which atherosclerosis contributes to coronary heart disease.

Answer: Atherosclerosis involves the build-up of fatty deposits (plaque) inside the coronary arteries, which narrows the arteries and restricts blood flow, potentially leading to heart attacks.

Question 3: What are the common risk factors associated with coronary heart disease?

Answer: High blood pressure, high cholesterol levels, smoking, poor diet, lack of exercise, obesity, and genetic factors.

Question 1: Calculate the Body Mass Index (BMI) of a person who weighs 70 kg and is 1.75 meters tall. Use the formula: BMI = weight (kg) / height (m)^2.

Answer: BMI = 70 / (1.75)^2 = 70 / 3.0625 ≈ 22.86 kg/m^2

Question 2: A patient's total cholesterol level is measured at 6.5 mmol/L. If a healthy level is considered below 5 mmol/L, by how much does this patient's level exceed the healthy maximum?

Answer: 6.5 mmol/L - 5 mmol/L = 1.5 mmol/L

Question 1: Describe a simple experiment to investigate the effect of a high-fat diet on blood cholesterol levels in rats. Include variables and safety precautions.

Answer: An experiment could involve dividing rats into two groups: one fed a normal diet and the other a high-fat diet over several weeks. Measure blood cholesterol levels using a lipid test kit at the start and end. Independent variable: diet type. Dependent variable: blood cholesterol level. Control variables: age, weight, environment. Safety precautions include handling animals ethically, ensuring proper disposal of biological waste, and avoiding contamination or hazards during testing.

Question 1: A group of 50 individuals were surveyed. 30 of them have high blood pressure, and 20 have high cholesterol levels. If 15 individuals have both conditions, calculate the number of individuals with only high blood pressure, only high cholesterol, and neither condition.

Answer: Only high blood pressure: 30 - 15 = 15; Only high cholesterol: 20 - 15 = 5; Neither condition: 50 - (15 + 5 + 15) = 15.

Question 1: Explain how lifestyle choices can influence the development of coronary heart disease. Include at least three factors in your answer.

Answer: Lifestyle choices such as diet, physical activity, smoking, and alcohol consumption significantly influence the risk of coronary heart disease. A diet high in saturated fats and cholesterol can lead to plaque formation in arteries. Lack of exercise contributes to obesity and high blood pressure. Smoking damages the lining of arteries and reduces oxygen transport, increasing the risk of atherosclerosis.

Question 2: Describe the role of LDL cholesterol in the development of coronary heart disease.

Answer: LDL cholesterol, often called 'bad' cholesterol, contributes to the formation of plaques inside the arteries, leading to atherosclerosis and increasing the risk of coronary heart disease.

Question 1: How can public health campaigns help reduce the incidence of coronary heart disease?

Answer: Public health campaigns can raise awareness about risk factors, promote healthy eating, encourage physical activity, discourage smoking, and provide screening services to detect early signs of heart disease.

Question 2: Discuss how advances in medical technology, such as stent procedures or bypass surgery, help treat coronary heart disease.

Answer: Advances like stent procedures and bypass surgery restore blood flow in blocked coronary arteries. Stents are small mesh tubes inserted into arteries to keep them open, reducing the risk of heart attacks. Bypass surgery involves creating a new pathway for blood flow around blocked arteries, improving oxygen supply to the heart muscle and reducing symptoms.