circulatory system

• What are the main components of blood?

  Red blood cells, white blood cells, platelets, plasma
• What is coronary heart disease?

  A condition caused by blocked coronary arteries
• What are some risk factors for coronary heart disease?

  High fat diet, smoking, lack of exercise
• How do coronary arteries function?

  They supply the heart with glucose and oxygen
• Why does the heart need to respire?

  To get energy for muscular contractions
• What is an atheroma?

  A fatty deposit that can block arteries
• What are the differences between arteries and veins?

  • Arteries:
  • More elastic fibers
  • More muscle fibers
  • Thicker walls
  • No valves
  • Smaller lumen
  • Veins:
  • Less elastic fibers
  • Less muscle fibers
  • Thinner walls
  • Have valves
  • Larger lumen
• What type of blood do arteries carry?

  Oxygenated blood
• What type of blood do veins carry?

  Deoxygenated blood
• What is the pressure difference between arteries and veins?

  Arteries have higher pressure than veins
• What is the function of red blood cells?

  Transport oxygen using haemoglobin
• What is the function of platelets?

  Clot the blood
• What is the function of white blood cells?

  Defend against infectious disease
• What does plasma carry?

  Dissolved substances like urea and carbon dioxide
• What is the pathway of blood circulation in the body?

  1. Vena cava returns deoxygenated blood to the heart
  2. Right atrium contracts, forcing blood through tricuspid valve
  3. Into right ventricle, which pushes blood to pulmonary artery
  4. Pulmonary vein returns oxygenated blood to left atrium
  5. Left atrium contracts, forcing blood through bicuspid valve
  6. Into left ventricle, which pumps blood into aorta
  7. Aorta carries blood to the body
• What is pulmonary circulation?

  Blood flow to the lungs and back to the heart
• What is systemic circulation?

  Blood flow to the body and back to the heart
• What is the role of capillaries in the circulatory system?

  • Extensive network around the body
  • Allows exchange of substances with blood
  • Thin walls facilitate diffusion
• What is the role of the heart?

  To push blood around the body
• What prevents the backflow of blood in the heart?

  The valves in the heart
• What are some treatments for coronary heart disease?

  • Statins
  • Angioplasty
  • Change of lifestyle
• What are semi-lunar valves?

  Valves that prevent backflow of blood
• Why does the left ventricle have a thicker muscular wall than the right ventricle?

  To provide enough pressure to push blood
• How does the structure of arteries support their function?

  Thicker walls and more muscle fibers handle high pressure
• How does the structure of veins support their function?

  Valves prevent backflow and larger lumen aids flow