Structure of the Heart
Physical Education: AQA GCSE, topic 1.2.4
Atria
The atria are the top 2 chambers of the heart. They fill up with blood received from the veins.
Atria structure
- The atria are small because the body only needs them to pump blood into the next chamber of the heart (ventricle).
Atria function
- The right atrium receives deoxygenated blood from the rest of the body through the superior vena cava.
- It then pumps blood through to the right ventricle.
- The left atrium receives oxygenated blood from the lungs through the pulmonary vein.
- It then pumps the blood into the left ventricle.
Ventricle
These are the bottom 2 chambers of the heart. They pump blood out through the arteries.
Ventricle structure and function
- The right ventricle has thinner walls and is less muscular.
- This is because less pressure is needed to pump the deoxygenated blood into the lungs via the pulmonary artery.
- The left ventricle has a thick, strong wall.
- This is because it needs to pump oxygenated blood to the entire body at a high pressure to make sure it gets there.
Remember:
- Right-side of the heart pumps deoxygenated blood.
- Left-side of the heart pumps oxygenated blood.
- Not all of the chambers contract at once. The atria contract together first, quickly followed by the ventricle. This is why we hear a ‘lub-dub’ sound.
Test yourself on Structure of the Heart
The right atrium
Which of the following describes the role of the left atrium?
The right ventricle
The roles of the left ventricle
Heart ventricles