PHSI 208 Lecture Notes - Lecture 5: Hemoglobin, Chronic Obstructive Pulmonary Disease, Pearson Education
Document Summary
Topics: determinants of diffusion (567-571, gas transport in the blood (571-572, hemoglobin and o2 transport (572-577) Random movement of molecules from a region of high concentration to a region of low concentration. What is going to affect the random movement of gas molecules from a region of high partial pressure to a region of low partial pressure: concentration gradient , surface area, barrier permeability, diffusion distance, solubility of gas. Under normal conditions surface area, diffusion distance and barrier permeability are constant. In a healthy individual concentration gradient is variable and the main determinant of diffusion. Normally doesn"t happen when left ventricle begins to fail, it doesn"t take blood out of pulm circuit properly, which would increase pressure in pulm capillaries, which would drive fluid out into intstit space. Co2 would still diffuse normally because it is highly soluble, but this would decrease o2. Fibrous connective tissue doesn"t allow gas to pass as easily.