Organisation

• 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 chamber of an atrium called?

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

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

  Prevent blood from flowing backwards
• 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 do pacemaker cells do in the heart?

  Produce electrical impulses for contraction
• What is an artificial pacemaker?

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

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

  Vessel carrying blood to the heart
• Why can the pulmonary artery carry deoxygenated blood?

  It carries blood away from the heart
• Why can the pulmonary vein carry oxygenated blood?

  It carries blood to the heart
• What are coronary arteries and their function?

  • Small arteries branching off the aorta
  • Supply oxygenated blood to the heart muscle
  • Ensure heart muscle receives nutrients
• What do coronary arteries supply to the heart?

  Oxygenated blood
• What is the significance of the coronary arteries?

  They provide oxygen and nutrients to the heart