Heart+lungs+disease etc

• What is the primary function of the lungs?


  To get oxygen into the bloodstream and remove carbon dioxide.
• Where are the lungs located in the body?


  The lungs are located in the thorax.
• What separates the thorax from the lower part of the body?


  The diaphragm separates the thorax from the lower part of the body.
• What protects the lungs?


  The lungs are protected by the ribcage.
• What is the pathway of air into the lungs?

  Air enters through the trachea and then into the bronchi.
• What happens to bronchi as they branch out?


  Bronchi branch into smaller tubes called bronchioles.
• What are alveoli responsible for?


  Alveoli are responsible for gas exchange.
• How does gas exchange occur in the alveoli?


  Oxygen diffuses into the blood, and carbon dioxide diffuses out into the alveoli.
• What is the concentration of oxygen and carbon dioxide in blood returning to the lungs?


  The blood contains high levels of carbon dioxide and low levels of oxygen.
• What happens to oxygen when blood reaches body cells?

  Oxygen is released from red blood cells to body cells.
• What is the cycle of blood flow in relation to the lungs and body cells?


  Blood circulates from the heart to the lungs, then to body cells, and back to the heart.
• What is the role of the heart in the circulatory system?


  The heart pumps blood around the body.
• What is the structure of the heart?


  The heart has four chambers: right atrium, right ventricle, left atrium, and left ventricle.
• What prevents backflow of blood in the heart?


  Valves in the heart prevent backflow of blood.
• How does blood flow through the heart?

  Blood flows into the atria, then into the ventricles, and is pumped out through arteries.
• What are the three types of blood vessels?

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


  Arteries carry blood away from the heart.
• What is the role of capillaries?


  Capillaries are involved in the exchange of materials at the tissues.
• What do veins do?


  Veins carry blood back to the heart.
• Why are artery walls thick?


  Artery walls are thick to withstand high pressure from the heart.
• What is the structure of capillary walls?


  Capillary walls are usually one cell thick to increase the rate of diffusion.
• What do platelets do?


  Platelets help clot blood at wounds to prevent excessive bleeding.
• What is plasma in the blood?


  Plasma is the liquid that carries red and white blood cells, platelets, nutrients, and waste products.
• What is the significance of the surface area to volume ratio in organisms?


  The surface area to volume ratio affects how easily materials move between an organism and its environment.
• What is the role of villi in the small intestine?


  Villi increase the surface area for quicker absorption of digested food.
• What is coronary heart disease?


  Coronary heart disease occurs when coronary arteries become blocked, restricting blood flow to the heart muscle.
• What are communicable diseases?


  Communicable diseases are contagious and caused by pathogens like bacteria and viruses.
• What are non-communicable diseases?


  Non-communicable diseases are non-contagious and often worsen over time.
• What are the key features of alveoli that maximize gas exchange?


  • Enormous surface area (75m² in humans)
  • Moist lining for dissolving gases
  • Very thin walls
  • Good blood supply
• What are the main components of blood and their functions?

  • Red Blood Cells: Carry oxygen
  • White Blood Cells: Defend against infection
  • Platelets: Help blood clot
  • Plasma: Carries cells, nutrients, and waste
• What is the process of gas exchange in the lungs?


  1. Oxygen enters the alveoli from the air.
  2. Oxygen diffuses into the blood.
  3. Carbon dioxide diffuses from the blood into the alveoli.
  4. Carbon dioxide is exhaled.
• What is the double circulatory system?


  • Heart pumps deoxygenated blood to lungs for oxygen.
  • Oxygenated blood is pumped to the rest of the body.
  • Blood returns to the heart to repeat the cycle.
• What are the characteristics of arteries, capillaries, and veins?


  • Arteries: Thick, elastic walls; carry blood away from the heart.
  • Capillaries: One cell thick; exchange materials at tissues.
  • Veins: Thinner walls; carry blood back to the heart with valves.
• What are the differences between communicable and non-communicable diseases?


  • Communicable: Contagious, caused by pathogens (e.g., bacteria, viruses).
  • Non-communicable: Non-contagious, often chronic (e.g., cancer, heart disease).