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 circulatory system?

  • Composed of blood, blood vessels, and heart
  • Blood carries oxygen and nutrients
  • Blood vessels hold blood
  • Heart pumps blood
• What is meant by a double circulatory system?

  It has two distinct loops for blood flow
• What does the first loop of the double circulatory system do?

  Carries deoxygenated blood to the lungs
• What happens to blood in the lungs?

  It gains oxygen
• What is the function of the second loop in the double circulatory system?

  Delivers oxygenated blood to the body
• How many chambers does the heart have?

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

  Atria
• What are the bottom chambers of the heart called?

  Ventricles
• What is the purpose of valves in the heart?

  Prevent blood from flowing backwards
• What is the path of blood through the heart?

  Vena cava and pulmonary vein to atria
• What happens when the atria contract?

  They push blood into the ventricles
• What do the ventricles do after the atria contract?

  They contract and push blood out
• How often does the heart cycle repeat?

  About 70 times a minute
• What is the role of pacemaker cells in the heart?

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

  A device that regulates heart contractions
• What does the term artery refer to?

  A vessel carrying blood away from the heart
• What does the term vein refer to?

  A vessel carrying blood to the heart
• Why can arteries carry deoxygenated blood?

  Because they transport blood away from the heart
• Why can veins carry oxygenated blood?

  Because they transport blood to the heart
• What supplies the heart with oxygenated blood?

  Coronary arteries
• What do coronary arteries do?

  They supply oxygen and nutrients to the heart
• What are the key components of the heart's structure?

  • Four chambers: atria and ventricles
  • Thick muscular walls
  • Valves between chambers and vessels
  • Arteries and veins connected
• How does the circulatory system maintain blood flow?

  • Heart pumps blood
  • Valves prevent backflow
  • Atria and ventricles contract in sequence
  • Pacemaker cells regulate heartbeat