Summary
The heart is a muscular organ responsible for pumping blood throughout the body. It consists of four chambers: the left and right atria and the left and right ventricles, separated by the septum.
- Atria — the upper chambers of the heart that receive blood from the veins. Example: The right atrium receives deoxygenated blood from the body via the vena cava.
- Ventricles — the lower chambers of the heart that pump blood out to the arteries. Example: The left ventricle pumps oxygenated blood to the body through the aorta.
- Atrioventricular valves — valves located between the atria and ventricles to prevent backflow of blood. Example: The bicuspid valve is between the left atrium and ventricle.
- Semilunar valves — valves located in the arteries leaving the heart. Example: The pulmonary valve is between the right ventricle and the pulmonary artery.
- Coronary arteries — arteries that supply oxygenated blood to the heart muscle. Example: Blockage of these arteries can lead to coronary heart disease.
Exam Tips
Key Definitions to Remember
- Atria: Upper chambers of the heart that receive blood.
- Ventricles: Lower chambers of the heart that pump blood out.
- Coronary arteries: Arteries that supply blood to the heart muscle.
Common Confusions
- Mixing up the left and right sides of the heart in diagrams.
- Confusing the function of atrioventricular and semilunar valves.
Typical Exam Questions
- What is the function of the septum? It separates oxygenated and deoxygenated blood in the heart.
- How does physical activity affect heart rate? Physical activity increases heart rate to supply more oxygen to muscles.
- What are the risk factors for coronary heart disease? Diet, lack of exercise, stress, smoking, genetics, age, and sex.
What Examiners Usually Test
- Identification of heart structures in diagrams.
- Understanding of blood flow through the heart.
- Effects of lifestyle choices on heart health.