Mammalian Heart

• Vertical Section through a Human Heart

  A) Vena Cava

  B) right atrium

  C) semi lunar Valves

  D) Vena Cava

  E) Tricuspid Valve

  F) right ventricle

  G) septum

  H) left ventricle

  I) valve tendons

  J) left atrium

  K) pulmonary vein

  L) left lung

  M) pulmonary artery

  N) left lung

  O) aorta

  
• The Mammalian Heart

  A) superior vena cava

  B) right pulmonary artery

  C) right pulmonary vein

  D) right atrium

  E) coronary arteries

  F) inferior vena cava

  G) right ventricle

  H) left ventricle

  I) left pulmonary vein

  J) left atrium

  K) left pulmonary artery

  L) aorta

  
• Heart

  • 3 tissue layers:
  • Epicardium (smooth outer)
  • Myocardium (thick muscular middle made of cardiac muscle)
  • Endocardium (smooth lining of heart chambers)
  • Aorta: Branches towards head and down to body
  • Largest artery
  • Pulmonary Arteries: One goes to left lung and other right
  • Vena Cavae: Superior vena cava brings deoxygenated from head and inferior brings it up from body
  • Into right atrium
  • Pulmonary Veins: Bring oxygenated blood back to left atrium from lungs
  • Coronary Arteries: On surface of heart
  • Branch from aorta
  • Bring oxygenated blood to cardiac muscle (myocardium)
• Vertical Section

  • Four chambers seen
  • Upper: Right and left atria
  • Lower: Right and left ventricles
  • Septum: Central cardiac muscle wall
  • Valves prevent backflow
  • Atrioventricular (AV) valves between atria and ventricles
  • Two semi-lunar valves in main arteries
  • Cordae tendonae (tendon cords) attached to AV valves and muscle pillars (papillary muscles) in ventricle walls
  • Prevent inversion of valves during muscle contraction
  • Papillary muscles control tension