Answer:
Heart function:
1. Deoxygenated blood enters the heart through the vena cava (vein) into the right atrium.
2. The right atrium contracts and blood moves through the tricuspid valve to the right
ventricle.
3. The ventricle contracts and blood exits the heart through the semilunar valve to the
lungs via the pulmonary artery.
4. Blood becomes oxygenated in the lungs and then returns to the heart via the
pulmonary vein, entering the left atrium.
5. The left atrium contracts and blood moves through the bicuspid valve into the left
ventricle.
6. The left ventricle contracts and oxygenated blood exits the heart past the semilunar
valve through the aorta (artery) and travels around the body, becoming deoxygenated.
The wall of the left ventricle is much thicker than the right side, as it must be able to
pump blood at high pressure around the entire body, rather than just to the lungs. The
walls of both ventricles are thicker than the atria walls.
7. The left and right sides of the heart are separated by the septum, which makes sure
that oxygenated and deoxygenated blood remain separate.
