The Heart and Circulation

• What type of circulatory system do fish have?

  Single circulatory system
• Where does deoxygenated blood go in fish?

  To the gills for oxygenation
• What happens to blood after it collects oxygen in fish?

  It passes to the organs
• What is a disadvantage of a single circulatory system?

  Blood loses pressure before reaching organs
• What type of circulatory system do humans have?

  Double circulatory system
• Where does deoxygenated blood go in humans?

  To the lungs for oxygenation
• What is the benefit of a double circulatory system?

  Blood can travel rapidly to body cells
• What are the four chambers of the human heart?

  • Left atrium
  • Right atrium
  • Left ventricle
  • Right ventricle
• What separates the atria from the ventricles in the heart?

  Valves
• Why does the heart appear back to front in diagrams?

  It shows the view as if looking at a person
• What blood vessel brings oxygenated blood from the body to the heart?

  Vena cava
• What carries blood from the heart to the lungs?

  Pulmonary artery
• What vessel carries oxygenated blood from the lungs to the heart?

  Pulmonary vein
• What is the main vessel that pumps blood from the heart to the body?

  Aorta
• What is the pattern of blood flow through the heart?

  1. Blood enters left and right atria
  2. Atria contract, forcing blood into ventricles
  3. Ventricles contract, pumping blood out of heart
  4. Valves prevent backflow into atria
• Why does the left ventricle have a thicker muscular wall than the right ventricle?

  It pumps blood around the entire body
• What are coronary arteries responsible for?

  Supplying oxygen to heart muscle cells
• What do coronary arteries branch from?

  Aorta
• What is the role of oxygen in heart muscle cells?

  Used in respiration for energy
• What controls the natural resting heart rate?

  A group of cells in the right atrium
• What is the pacemaker?

  A group of cells controlling heart rate
• What is an artificial pacemaker?

  A device correcting heart rate irregularities
• What is the purpose of the artificial pacemaker?

  To correct irregularities in heart rate
• What should you be able to describe after watching the video?

  • Structure of the heart
  • How the heart pumps blood around the body