respiratory system

• what is the respiratory system?


  a group of organs and tissues that work together to help you breathe
• describe the pathway of gas through the respiratory system


  • nose
  • trachea
  • bronchi
  • bronchioles
  • alveoli
  • capillaries
• what is the function of mucus in the respiratory system?


  it traps harmful substances and organisms preventing entry into lungs
• where are ciliated epithelial cells found?


  lining the surface of the respiratory tract
• what are the lungs?

  a pair of organs consisting of the bronchioles, alveoli and surrounding tissues
• what is the thorax?


  • area between the neck and abdomen
  • includes organs found within the chest and lungs
• what is ventilation?


  movement of fresh air into the lungs and stale air out of lungs

  • inhalation
  • exhalation
• what does ventilation require?


  • rib cage
  • intercostal muscles
  • riaphragm
• what is inspiration?


  breathing in
• what is expiration?


  breathing out
• how is ventilation modelled?


  bell jar model
• what are the alveoli?


  a cluster of air sacs in the lungs where gas exchange occurs
• describe the process of gas exchange at the alveoli


  • oxygen diffuses from the air in the alveoli into the blood in the capillaries
  • carbon dioxide diffused from blood in the capillaries into air in the alveoli
• how are alveoli adapted for gaseous exchange?


  • large surface area
  • rapid blood floow maintains a steep concentration gradient
• what chemicals found in the tobacco smoke damage the lungs?

  • tar
  • nicotine
  • carbon monoxide
• how does tar effect the airways?


  • stimulates mucus production
  • leads to smokers cough
• what are the effects of nicotine on the body?


  • increases heart rate
  • damages lungs
  • addictive
• wheres the site of gas exchange in the lungs?


  alveoli