1. The Respiratory System
PSE4U
Mr. MacMillan

2. What Makes Up the Respiratory System?
The Conductive Zone
Nose, pharynx, trachea, bronchi, bronchioles
The Respiratory Zone
Respiratory bronchioles, alveolar ducts, alveoli sacs.

4. Main Functions Supply Oxygen to the blood Remove CO2 from the blood
Regulate blood pH

5. Internal Respiration
Is the exchange of gases at the tissue level where Oxygen is delivered and Carbon Dioxide is removed

6. External Respiration
The processes that occur within the lung involving the exchange of Oxygen and Carbon Dioxide

8. Mechanisms of Breathing
Diaphragm
Contracts and moves downward towards the abdominal cavity when stimulated by the brain
Ventilation
The combination of inspiration (breathing in) and expiration (breathing out)
Tidal Volume
Volume of air in each breath
Respiratory Frequency
The number of breaths taken per minute

9. Controlling Ventilation
Respiratory Control Centre
Found within brain stem
Medulla oblongata and pons

10. Lung Volumes Static Lung Volume Dynamic Lung Volume
Determined by actual structure of lung
Dynamic Lung Volume
Dependent, not only on volume, but on the movement or flow of air
Three important Static Lung volumes
Total lung capacity, vital capacity, residual volume
TLC = VC + RV

11. Gas Exchange Diffusion
The movement of gas, liquid or solid from a region of high concentration to low concentration.

12. Oxygen Transport 2% of Oxygen found within plasma of blood Hemoglobin
Specialized protein found in erythrocytes that binds to Oxygen

13. Carbon Dioxide Transport
Small amount is dissolved in the plasma (5 – 10%)
90 – 95% of CO2 diffuses into erythrocytes, passed to alveoli and is exhaled

14. Ventilation and pH
Blood pH is a measure of how acidic and basic blood is
Blood pH is close to 7.4 – neutral is 7
More acidic during exercise – lactic acid (decreased pH)
Ventilation increase pH back to normal