The Heart

• The left wall of the heart is thicker than the right wall to pump blood at higher pressures to the whole of the body.
• The superior vena cava carries deoxygenated blood from the head, neck, arms, and chest to the right atrium.
• The inferior vena cava carries deoxygenated blood from the legs, feet, and organs in the abdomen and pelvis to the right side of the heart.
• The inferior vena cava is the body's largest vein.
• The superior vena cava is the body's second biggest vein.
• The four chambers of the heart are:

  • right atrium
  • left atrium
  • right ventricle
  • left ventricle
• The aorta is the largest artery in the body.
• The aorta carries oxygenated blood from the heart to the circulatory system.
• The pulmonary artery carries deoxygenated blood from the heart to the lungs.
• The pulmonary vein carries oxygenated blood from the lungs to the left atrium.
• What valves separate the atria and ventricles on each side of the heart?

  Tricuspid (right side) and mitral (left side) valves.
• What vessels supply blood to the heart muscles themselves?

  Coronary arteries.
• What is the main job of valves?

  Valves prevent backflow.
• Mild heart attack ----> small vessel blocked so small area of heart tissue affected.
• Severe heart attack ----> large area of heart tissue is damaged -> cardiac arrest.
• Atrioventricular valves prevent backflow of blood from ventricles to atria.
• Semi-lunar valves prevent backflow of blood from arteries to ventricles.