smoking

• What is known to damage the lungs in several ways?

  Smoking
• What are carcinogens?

  Chemicals that cause cancer
• What is tar in relation to tobacco smoke?

  A sticky substance that clogs the bronchioles and alveoli
• What is the main problem with nicotine?

  It is extremely addictive and directly damages the lungs
• What is carbon monoxide?

  A poisonous gas that makes it difficult for red blood cells to carry oxygen
• Name two other harmful substances found in tobacco smoke.

  Ammonia and formaldehyde
• What are the effects of smoke on the lungs?

  • Lung cancer
  • Other cancers (e.g., mouth, esophagus, bladder, kidney)
  • Emphysema (damage to alveolar walls)
  • Paralysis of cilia lining the respiratory system
• Why is it important that the walls of the alveoli are very thin?

  To facilitate gas exchange
• Which structures cause the ribs to move during breathing?

  The intercostal muscles
• When the lungs expand, why does air move into them from the outside?

  Due to differences in pressure
• What role does mucus play in the protection of the lungs?

  It traps dust and microbes
• Which chemical in tobacco makes smoking addictive?

  Nicotine
• What is aerobic respiration?

  • A series of enzyme-controlled reactions
  • Occurs when oxygen is available
  • Uses glucose and oxygen to release energy
  • Produces carbon dioxide and water
• What is anaerobic respiration?

  • Occurs when oxygen is not available
  • In animals, glucose is broken down into lactic acid
  • Produces less ATP than aerobic respiration
• What happens to the oxygen debt after exercise?

  It is repaid by breathing faster and deeper than normal
• Why do larger animals need a respiratory system?

  Because diffusion cannot supply enough oxygen for their volume
• What structures make up the respiratory system in humans?

  • Nasal cavity
  • Trachea
  • Bronchi
  • Bronchioles
  • Alveoli
  • Lungs
  • Diaphragm
  • Ribs
  • Intercostal muscles
• How does mucus function in the respiratory system?

  • Traps dust and microbes
  • Cilia move mucus to the top of the trachea
  • Mucus can be swallowed
• What happens to the cilia when they are paralyzed by tobacco smoke?

  The mucus sinks into the lungs, carrying dust and microbes
• What causes breathing in and out?

  • Movements of the ribs and diaphragm
  • Inspiration (breathing in)
  • Expiration (breathing out)
• Where does gas exchange occur in the respiratory system?

  At the alveoli
• What does expired air contain compared to inspired air?

  More carbon dioxide and less oxygen
• What is a major contributory factor in lung cancer and emphysema?

  Smoking