The Respiratory System

Chapter 22

Functions Surface for gas exchange Movement of air Protection of respiratory

pathways Sound production Assistance with olfaction

Conduction Zone

Respiration Zone

Respiratory Membrane Simple squamous epithelia

Pneumocytes type 1 Pneumocytes type 2 (septal) Alveolar macrophages

Respiratory membrane Epithelia Endothelia Shared (fused) basement

mebrane

http://iws.collin.edu/mweis/Images/Histology/2402%20histology/Respiratory%20Histo/labeled%20resp%20histo/resp_phys_alveolus_typecells_histo_labeled.png

Mechanics of Breathing(exchange of air between atmosphere and lungs)

Pulmonary ventalation maintains alveolar ventilation

Atmospheric pressure effects ventilation Boyles Law P=1/V (http://www.grc.nasa.gov/WWW/k-12/airplane/aboyle.html)

Ventilation causes volume and pressure changes Intrapulmonary pressure Intrapleural pressure

Mechanics of Breathing

Physical Factors Airway resistance Alveolar surface tension Lung Compliance

change in lung volume/change in lung pressure

Gas Exchange Dalton's Law =the partial pressure of a gas is the

pressure contributed to the mixture of gases Henry's Law =the amount of gas in solution is

directly proportional to the partial pressure Partial pressures gradients drive gas exchange Amount of gas in solution depends upon the

solubility

Gas Transport Red blood cells are sacs of hemoglobin bound O2 CO2 uses 3 methods

Conversion to carbonic acid (HCO3-) =70% Bound to hemoglobin = 23% Dissolved in plasma =7%

Gas Transport

Control of Respiration

Control of Respiration

Control of Respiration

Control of Respiration

Respiratory Adjustments Exercise High Altitude Scuba Diving Hyperbaric Chambers