Ventilation

Ventilation of the lungs

63 cards   |   Total Attempts: 188
  

Cards In This Set

Front Back
Airflow is governed by the same principles of......
as blood flow
Flow, pressure and resistance
Atmospheric pressure
Drives respiration--amt of pressure exerted from the atmosphere
Intrapulmonary pressure
..also referred to as_______
Pressure within the lungs (alveoli)
aveolar pressure
Direction of airflow depends on:
Gradient between atmospheric pressure and intrapulmonary pressure
Negative pressure:
Implies below atmospheric pressure
Positive pressure:
Implies above atmospheric pressure (out of the lungs)
Boyles law
Pressure of a gas in a closed container is inversely proportional to the volume of its container at a constant temperature
Charles' law
Volume of a gas in a close container is directly proportional to its absolute temperature at a constant pressure
Dalton's law
Each gas in a mixture exerts its own partial pressure independent of the partial pressures of the other gases in the mixture
Henry's law
The amount of gas that dissolves in a liquid is directly proportional to its solubility in that liquid and its partial pressure
Inspiration
--for air to flow into the lungs
...this is accomplished by
Intrapulmonary pressure must be less than atmospheric air pressure
...increasing volume of the lungs
When diaphragm and external intercostal muscles contract:
Volume of thoracic cavity increases
Contraction of the diaphragm:
Increases volume of the thoracic cavity from top to bottom
Contraction of external intercostal muscles:
Pulls ribs upward and outward to increase volume of thoracic cavity from front to back
Consequences of contractions:
Because visceral and parietal pleurae adhere strongly to one another, lung volume will expand as volume of thoracic cavity expands