2. Ch 37 Gas Exchange AP lecture

3. Background information Diffusion Barometric pressure Oxygen in the air

4. Mammal Oral cavity and nasal passage Pharynx – Larynx Trachea Bronchi – Bronchioles – Alveoli

6. Inhalation and exhalation Thoracic cavity houses lungs and diaphragm InhalationExhalation Diaphragm contractsDiaphragm relaxes Thoracic cavity expandsThoracic cavity contracts Lungs expandLungs contract Air inAir expelled

8. http://teachhealthk- 12.uthscsa.edu/studentresources/anatomyofb reathing3.swf http://teachhealthk- 12.uthscsa.edu/studentresources/anatomyofb reathing3.swf

9. Negative feedback Breathing is an involuntary function of the CNS ; specifically medulla oblongata Rate is regulated by carbon dioxide Major site medulla oblongata Carbon dioxide indirectly controls breathing via changes in pH levels

10. Concentration gradient & pressure drives movement of gases into & out of blood at both lungs & body tissue Diffusion of gases bloodlungs CO 2 O2O2 O2O2 bloodbody CO 2 O2O2 O2O2 capillaries in lungscapillaries in muscle

11. Transporting gases Oxygen carried by hemoglobin, protein in red blood cells Each hemoglobin can bind four oxygen molecules

12. http://highered.mcgraw- hill.com/sites/0072495855/student_view0/ch apter25/animation__gas_exchange_during_re spiration.html http://highered.mcgraw- hill.com/sites/0072495855/student_view0/ch apter25/animation__gas_exchange_during_re spiration.html