Smoking

• What does the air we breathe contain that can be dangerous?

  Gases and bacteria
• Why do inspired air and expired air contain different proportions of gases?

  We use up oxygen and produce carbon dioxide
• What are the proportions of gases in inspired and expired air?

  • Oxygen: Inspired 21%, Expired 16%
  • Carbon dioxide: Inspired 0.04%, Expired 4%
  • Water: Inspired Variable, Expired Saturated
  • Nitrogen: Both 78%
• How can we test expired air for carbon dioxide?

  Using limewater
• What is the function of cilia in the respiratory system?

  To move mucus up the trachea
• What do goblet cells produce?

  Mucus
• What do ciliated epithelial cells do in the airways?

  They line the airways
• What effect does smoking have on cilia?

  Smoking paralyses the cilia
• What harmful particles does cigarette smoke contain?

  Particles that clog mucus
• What are the effects of tar and nicotine in cigarette smoke?

  • Tar: Contains carcinogens causing lung cancer
  • Nicotine: Addictive substance
• What disease is caused by smoking that affects lung tissue?

  Emphysema
• How does emphysema affect gas exchange?

  It reduces surface area for gas exchange
• What happens to a patient with emphysema during normal activities?

  They struggle to get enough oxygen
• What is the bell jar model used for in respiratory system modeling?

  • Balloons represent lungs
  • Bell jar represents ribs
  • Rubber sheet simulates diaphragm movement
• What does the huff and puff apparatus demonstrate?

  Carbon dioxide levels in inspired and expired air
• What happens to limewater when expressed air is bubbled through it?

  It turns very cloudy
• Why does expressed air cause limewater to turn cloudy?

  It shows increased carbon dioxide