Coronary heart disease

Coronary heart disease (CHD) is caused by damage to the walls of the coronary artery.

Explain two differences between the structure of the wall of an artery and the wall of a vein.

The diagram shows a cross-section of a coronary artery from a healthy person and from a person with CHD.

Artery from a healthy person Artery from a person with CHD The heart needs to respond to extra demands during exercise. Explain why, during exercise, the heart of a person with CHD would not respond as efficiently as the heart of a healthy person.

Genetics and smoking are two risk factors for CHD. The alleles of some genes increase the risk of developing CHD in people. These are known as risk factor alleles. Scientists compared the relative risk of developing CHD in people with different numbers of these risk factor alleles. The scientists also compared the risk of developing CHD for non-smokers and smokers. The graph shows the scientists’ results.

Give one risk factor for CHD, other than genetics and smoking.

Comment on the relationship between the number of risk factor alleles and smoking on the risk of developing CHD. Use data from the graph to help your answer.

The diagram shows a transverse section through a human heart.

Draw an X on the diagram to show the position of the septum.

State two differences between the composition of the blood in the coronary artery and the composition of the blood in the coronary vein.

Explain the differences between the left ventricle wall and the right ventricle wall.

The development of coronary heart disease is linked to a number of factors.

Explain how these factors can increase the risk of developing coronary heart disease.

The diagram shows the human blood circulation system.

What is the name of the blood vessel labelled Z?

Which labelled blood vessel contains blood with the lowest concentration of carbon dioxide?

Give two differences in the structure of the blood vessel labelled V and the structure of the blood vessel labelled Y.

High blood pressure and the presence of certain genes are risk factors for coronary heart disease.

Give two other risk factors for coronary heart disease.

Scientists compared the relationship between blood pressure and the number of deaths from coronary heart disease in Northern Europe, Eastern Europe and Japan.

The graph shows their results.

A high blood pressure is considered to be above 130 arbitrary units.

Use the graph and your own knowledge to comment on the causes of death due to coronary heart disease in each region.

The diagram shows the human heart with four chambers and four blood vessels labelled.

Which blood vessel brings deoxygenated blood to the heart?

Which chamber pumps oxygenated blood away from the heart?

Explain the difference in the wall of chamber S and the wall of chamber Z.

Humans need a balanced diet for healthy growth and development.

Give the function of three different components of a balanced diet.

Scientists investigated the link between body mass and coronary heart disease in a population in Australia.

The scientists recorded the number of heart attacks in a population of 850 people for a period of 20 years.

They classified the people as normal mass, overweight or obese.

They calculated rates of heart attacks that allowed a valid comparison to be made between the groups.

Evaluate what the data shows about the relationship between classification of body mass, age and heart attacks.

The diagram shows a section through a human heart with the chambers labelled P, Q, R and S.

Which chambers contain deoxygenated blood?

Explain why two of the valves in this heart are closed.

Heart disease is a major risk to health in the United Kingdom.

In a study, the number of people with heart disease was recorded.

The table shows the results of the study.

Give two conclusions that can be made from this study.

The population of the United Kingdom is 65 million, of which half are male.

Calculate the number of males with heart disease in the age range 18 to 44.

Explain how heart disease can affect a person’s health.

Arteries and veins are involved in the circulation of blood.

How do arteries differ from veins?

The diagram shows a section through a coronary artery from a person who has heart disease.

Using measurements from the diagram, calculate the percentage decrease in the diameter of the lumen where the fat deposit is thickest.

percentage decrease =_........ %

Explain how the fat deposit would affect the type of respiration in the heart muscle.

A high fat diet increases the risk of heart disease. Give two other factors that can increase the risk of heart disease.

Small arteries in the skin have a role in homeostasis. In an investigation, the diameter of a small artery in the skin is measured in a cold environment and then in a warm environment. The blood flow in this artery is also measured. The table shows the results.

Explain these changes in diameter and blood flow when moving from a cold environment to a warm environment.