the heart and blood

❤ The Heart

🔹 Function:

• Pumps blood around the body in a double circulatory system:

  1. Right side pumps deoxygenated blood to the lungs.

  2. Left side pumps oxygenated blood to the rest of the body.

🔹 Structure:

• 4 chambers:

  • Right atrium and right ventricle (deoxygenated blood)

  • Left atrium and left ventricle (oxygenated blood)

• Valves: prevent backflow of blood.

• Coronary arteries: supply the heart muscle with oxygenated blood.

🔹 Blood Flow Through the Heart:

1. Blood enters right atrium from the body (via vena cava).

2. Goes to right ventricle, then to lungs (via pulmonary artery).

3. Returns to left atrium from lungs (via pulmonary vein).

4. Goes to left ventricle, then to body (via aorta).

🔹 Pacemaker:

• The natural pacemaker is in the right atrium – controls heart rate.

• Artificial pacemakers can be implanted to correct irregular heartbeat.

🩸 Blood Vessels

🩻 Blood Components