BIO-0014 Lecture Notes - Lecture 23: Pressure Gradient, Partial Pressure, Circulatory System
18 Apr 2017
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Document Summary
Water is 1000 times more dense than air. Humans use tidal respiration- air moves in one direction, stops, reversed. Inertial force of water too high- humans cannot receive oxygen from water. Henry"s law: amount that a gas can dissolve in solution. P= partial pressure of gas k= solubility constant of gas. Diffusion- relies on thermal energy (no atp), efficient over short distance. Works efficiently when distance is a micron or less. Bulk flow- requires atp to generate pressure gradient, efficient over long distances. Total pressure gradient (of air- respiratory, of blood- cardiovascular) necessary. Pressure gradient for the bulk flow of air into and out of lungs established by respiratory muscles. Pressure gradient for the bulk flow of blood around body"s blood vessels is established by the heart. Blood more viscous than air- heart has to work harder than lungs. Atmospheric > lung - oxygen moves into lungs. Systemic arterial blood oxygen = 100 mm hg.
