The Heart

• What is the role of the circulatory system?

  To transport oxygen and nutrients
• What are the three main components of the circulatory system?

  Blood, blood vessels, and heart
• What does blood carry in the circulatory system?

  Oxygen and nutrients
• How does the heart function in the circulatory system?

  It pumps blood to keep it moving
• What is the structure of the heart?

  • Four chambers: two atria and two ventricles
  • Thick muscular walls
  • Valves between chambers and vessels
• How many chambers does the heart have?

  Four chambers
• What are the top chambers of the heart called?

  Atria
• What is the individual term for one atrium?

  Atrium
• What prevents blood from flowing backwards in the heart?

  Valves
• Describe the path blood takes through the heart.

  1. Blood enters via vena cava and pulmonary vein
  2. Flows into right atrium and left atrium
  3. Atria contract, pushing blood into ventricles
  4. Ventricles contract, sending blood to pulmonary artery and aorta
  5. Cycle repeats
• How many times does the heart cycle in a minute?

  About 70 times
• What is the function of pacemaker cells in the heart?

  They produce electrical impulses for contraction
• What is an artificial pacemaker used for?

  To regulate heart contractions
• What does the term artery refer to?

  Any vessel carrying blood away from the heart
• What is the difference between arteries and veins?

  Arteries carry blood away; veins carry blood to
• What does the pulmonary artery carry?

  Deoxygenated blood
• What does the pulmonary vein carry?

  Oxygenated blood
• What are coronary arteries responsible for?

  Supplying oxygenated blood to the heart
• What is the overall function of the circulatory system?

  • Transport oxygen and nutrients
  • Remove waste products
  • Maintain body temperature