lungs

• describe role of lungs

  gas exchange of oxygen and carbon dioxide for and from respiration
• give pathway of air through lungs

  1. mouth / nose
  2. trachea
  3. bronchi
  4. bronchioles
  5. alveoli
• describe alveoli

  gas exchange surface of lungs
• describe gas exchange in alveoli

  oxygen - diffuse from alveoli to blood

  carbon dioxide - diffuse from blood to alveoli
• give adaptations of alveoli

  large surface area, good blood supply and thin and moist walls