Chapter 4: Circulation

• What are the main parts of the circulatory system?

  Blood vessels, heart, and blood
• What is the function of blood vessels?

  They carry blood around the body
• What is the role of the heart in the circulatory system?

  It pumps blood around the body
• What does blood transport in the body?

  Substances around the body
• Describe the pathway of deoxygenated blood through the heart.

  Vena cava → right atrium → right ventricle → pulmonary artery
• How does oxygenated blood return to the heart?

  By the pulmonary veins into the left atrium
• What is double circulation?

  Two transport systems for blood in the body
• What does the first transport system in double circulation do?

  Carries blood from heart to lungs and back
• What is the role of pacemakers in the heart?

  Control the resting heart rate
• What do pacemakers send to the heart?

  Electrical impulses from atrium to ventricle
• What is an artificial pacemaker?

  An electrical device correcting heart irregularities
• What is the function of an artificial heart?

  Pumps blood using air pressure
• Why might an artificial heart be used?

  To keep patients alive while waiting for a transplant
• What are the risks associated with artificial hearts?

  Scar tissue and clotting development
• What are the three types of blood vessels?

  Arteries, veins, and capillaries
• What is the function of arteries?

  Carry blood from heart to organs
• Describe the structure of arteries.

  Thick walls, narrow lumen, no valves
• What is the function of veins?

  Carry blood from organs to heart
• Describe the structure of veins.

  Thin walls, large elastic lumen, has valves
• What is the function of capillaries?

  Facilitate gas exchange
• Describe the structure of capillaries.

  Thin walls, narrow lumen, no valves
• What is coronary heart disease?

  Fatty deposits in coronary arteries
• What is a stent?

  A metal mesh to keep arteries open
• What is a coronary bypass graft?

  Attaching a blood vessel to bypass blockage
• What happens to faulty valves?

  They may stiffen or develop leaks
• What are biological valves?

  Valves from humans or other mammals
• What are mechanical valves?

  Valves made from materials like titanium
• What is plasma's role in blood?

  Transport medium
• What are platelets?

  Small fragments of cells for clotting
• What do red blood cells transport?

  Oxygen for aerobic respiration
• What are the two types of white blood cells?

  Lymphocytes and phagocytes
• What is a pathogen?

  A disease-causing microorganism
• What is a transmissible disease?

  A disease passed from host to host
• What is an antigen?

  A protein on the surface of a cell
• What is an antibody?

  Attaches to foreign antigens to destroy them
• What are the two types of antigens?

  Antigen A and Antigen B
• Why is blood typing before transfusion vital?

  Errors can be fatal due to immune response
• What is an immunosuppressant drug?

  Suppresses the immune system to prevent rejection