1. - video

2. Passage of air from outside the body to the lungs and gas exchange
Respiratory
System
Passage of air from outside the body to the lungs and gas exchange

3. Breathing vs Respiration
3 Main Functions:
supply oxygen to the blood
remove carbon dioxide from the blood
regulate blood pH
Breathing vs Respiration
3 Types: (movement of gases)
-getting air to the lungs
External  O2/CO2 exchange in lungs
Internal  gas exchange at the tissue level
Cellular  utilizing O2 for energy
Conductive Zone vs Respiratory Zone

4. The Conductive Zone Nasal cavity Mouth Pharynx Larynx Trachea Bronchii
warm
humidfy
filter
Bronchioles
-hairs
-mucous

5. ? The Respiratory Zone -video Alveolar sac Respiratory bronchiole
Terminal bronchiole
Alveolar sacs spread out = tennis court!!!!!
gas exchange
each sac covered by network of capillaries  short diffusion
- grape like structure
-HUGE surface area ?
Pulmonary vein
Pulmonary artery

6. Process
of Breathing
“movement of air from outside the body to the lungs”
Diaphragm is the principle muscle in controlling breathing  upon stimulation, will contract

7. Air outside  Air inside
PRESSURE CHANGES
High pressure  Low pressure

8. So how do we breath? Diaphragm contracts (moves down)
Chest increases in size  air space increases
Decrease in pressure in the lungs
.: Pressure outside body > inside body
Air rushes in
INHALATION (active process)
EXHALATION (passive/active)
Diaphragm relaxes
Chest decreases in size  air space decreases
Increase in pressure in the lungs
.: Pressure outside body < inside body
Air rushes out
Forced breathing
Quiet breathing

10. Ventilation at maximum?
Ventilation (VE )
“The volume of air that is moved in 1 minute.”
Air in and out
VE (L/min)= VT (L) x f (breaths/min)
Tidal Volume
volume of air in each breath
rest = 0.5 L/min
max = 3-4 L/min
Respiratory frequency
number of breaths per minute
rest = 12 breaths/min
max = breaths/min
Ventilation at maximum?

11. What controls ventilation?
Graphically????
What controls ventilation?
CNS  medulla oblongata (contraction/relaxation of muscles)
-O2 vs CO2 needs
Bicarbonate (HCO3)
-blood pH (buffer)

12. Lung Volumes TLC = VC + RV Static vs Dynamic
So we’ve got the air to the lungs. . .
Lung Volumes
Static vs
Dynamic
-volumes determined by structure of lung
-volumes dependent on movement of air
TLC = VC + RV
Total Lung Capacity
max air lungs hold
Vital Capacity
max air exhaled following max inhale
Residual Volume
remaining air in lungs after max exhale

13. Gas Exchange (Alveoli)
Now what happens with the air in the lungs?
Gas Exchange (Alveoli)
Respiration
Lungs  O2  blood  CO2  Lungs
DIFFUSION!!
* Read pages *
Describe partial pressures
Explain the 3 factors that contribute to gas exchange
Diffusion pathway
Barrier thickness
Surface area
-video

14. O2 Transport 2% dissolved in plasma
VAST majority binds to hemoglobin (1.34 ml of O2 per molecule)
OXYHAEMOGLOBIN DISSOCIATION CURVE
-Percent saturation of hemoglobin (SbO2%)
-Pressure of oxygen in the blood (PO2)
What does this graph illustrate?
The lower the PO2, the less O2 will bind to hemoglobin

15. Carbon Dioxide Transport
Read page 125: Carbon Dioxide Transport and Ventilation and the Regulation of Blood pH
Make your own brief notes on:
a) The 3 ways in which CO2 is transported in the blood
b) The role pH plays in human ventilation