Unit 3 Mechanisms of Breathing

Question 1

Atmospheric Pressure (P atm)

Answer 1

Pressure exerted by the air on the body

Question 2

Intrapulmonary Pressure (P pul)

Answer 2

Pressure on the alveoli
-will oscillate with breathing but always equalize to atmospheric pressure in between breaths

Question 3

Intrapleural Pressure (P ip)

Answer 3

Pressure in pleural cavity
-will oscillate with breathing but always negative 4 mmHg to intrapulmonary pressure

Question 4

Why is P ip negative

Answer 4

Balance between tendency of alveoli/lungs to collapse and tendence of thoracic cavity to exapnd

Question 5

Loss of transpleural pressure causes lung to collapse

Answer 5

pneumothorax and hemothorax

Question 6

Boyle’s Law

Answer 6

The pressure of a gas within a container is inversely related to the volume of the container
-if the volume of a container that contains a gas is reduced, the pressure increases
-if the volume increases, the pressure decreases