Part 3 Respiratory gases Exchange
1 Part 3 Respiratory Gases Exchange
Blood flow Bood fle Bronchiole Pulmonary venule man pumonary Blcod Pulmonar arterio Capillary network o surface of aly Af in alves Epithelial ce of alveolus Can
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I Physical Principles of Gas Exchange
3 I Physical Principles of Gas Exchange
Partial pressure The pressure exerted by each type of gap n a mixture Concentration of a gas in a liquid determined by its partial pressure and its solubility coefficient
4 • Partial pressure – The pressure exerted by each type of gas in a mixture • Concentration of a gas in a liquid – determined by its partial pressure and its solubility coefficient
Partial Pressures of gases Basic Composition of Air 79% Nitrogen o Oxygen 0% Carbon Dioxide In a mixture of gases, each gas exerts a partial pressure proportional to its mole fraction Total Pressure =sum of the partial pressures of each gas Total Pressure(at sea level) barometric 760 mm hs 760mm Hs Pgas=Pb X Fgas PN2=760X0.79=600.4mmHg PO2=760X0.21=1596mmHg
5 Partial Pressures of Gases Basic Composition of Air • 79% Nitrogen • 21% Oxygen • ~ 0% Carbon Dioxide In a mixture of gases, each gas exerts a partial pressure proportional to its mole fraction. Total Pressure = sum of the partial pressures of each gas Pgas = Pb x Fgas PN2 = 760 x 0.79 = 600.4 mm Hg P02 = 760 x 0.21 = 159.6 mm Hg Total Pressure (at sea level) Pbarometric = 760 mm Hg Pb 760 mm Hg Pb