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MSDMERCK MANUALConsumer Version
HEALTH TOPICSHEALTHY LIVINGSYMPTOMSEMERGENCIESDRUG INFORESOURCESCOMMENTARYABOUT US
HEALTH TOPICSHEALTHY LIVINGSYMPTOMSEMERGENCIESDRUG INFORESOURCESCOMMENTARY
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Biology of the Heart and Blood Vessels
  • Biology of the Heart
    • What is the heart?
    • How does the heart work?
      • What are the heart chambers?
      • What are heart valves for?
      • What is the heart's electrical system?
      • Why does the heart need blood vessels?
    • What can go wrong with the heart?
  • Biology of the Blood Vessels
    • What are blood vessels?
    • What can go wrong with blood vessels?
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