Respiratory System

Question 1

4 main functions of respiratory system?

Answer 1

1. Pulmonary Ventilation
   - moving air in / out of lungs
2. External Respiration
   - gas exchange @ lungs btwn lungs & blood
3. Transport of Respiratory Gases ( CO2 / O2 )
4. Internal Respiration
   - exchange gas @ tissues btwn the blood & tissues

Question 2

Other function of the respiratory system?

Answer 2

1. pH regulation
2. Olfaction
3. Filters
4. Speech
5. Temp regulation

Question 3

What are the 3 pressure gradients in respiratory ventilation?

Answer 3

1. Respiratory pressures:
   - compared to Patm = 760 mmHg (sea level)
   - @ 18k ft = 1/2 atm
   - @33 ft under sea level = (+ 1 atm)
2. Interpulmonary Presseure
   > P w/ in alveolus = Palv
   - Palv = 758 —> neg P —> inhalation
   - Palv = 762 —> pos P —> exhalation
   Boyle’s Law => lungs are passive
3. Intrapleural pressures
   > P w/in pleural cavity = Pip
   - pleural cavity is sealed
   - always negative compared to Patm
   Prevent lung collapse:
   - help keep lung inflated
   - surface tension of pleural fluid

Question 4

What are the factors that influence ventilation?

Answer 4

1. Resistance = friction w/ in airway
   - ⬆️ R ==> ⬇️ Ventilation rate
   - ⬇️ R ==> ⬆️ Ventilation rate
2. Surface Tension
   - surfactant
3. Compliance = Elasticity
   - Lungs
   -Skeletal system (Rib Cage)