6.4 Gas Exchange

6.4 Gas Exchange

1. NATURE OF SCIENCE

   • Obtain evidence for theories
     • Epidemiological studies have contributed to our understanding of the causes of lung cancer

2. Ventilation

   • Gas exchange
     • Cell respiration
     • Trachea + bronchi + bronchioles
       • Alveoli
         • Cells
           • Type I cells
             • Thin alveolar cells that are adapted to carry out gas exchange
           • Type II cells
             • Secrete a solution containing surfactant
               • Prevent the sides of the alveolus adhering to each other
                 • By reducing surface tension
         • Draw a diagram to show the structure of an alveolus and and adjacent capillary
   • Antagonistic muscle action
     • Diaphragm
       • Pressure changes inside the thorax that force air in and out of the lungs
     • External + Internal Intercostal muscles
     • Abdominal muscles
   • Monitoring of ventilation in humans at rest and after mild and vigorous exercise
     • Spirometer + LoggerPro
       • Ventilation rate
       • Tidal volume

3. Diseases

   • Aim 8
     • Causes and social consequences
       • Lung cancer
       • Emphysema