Physiology 3120 Lecture Notes - Ascending Aorta, Capillary Pressure, Pressure Gradient

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Tom Stavraky

Document Summary

Vascular function: relationship between pressure, flow, and resistance. Pressure gradient makes the blood flow; gradient is the difference between the beginning and end of the blood vessel/systemic circulation. In systemic circulation, the pressure gradient is equal to p1 (pressure at end of vessel is. Flow = pressure gradient/resistance; flow is proportional to pressure gradient & inversely. Resistance depends on viscosity (directly), length of vessel (directly) and vessel radius (inversely. The relationship between these 4 variables is summarized in the poiseuille-hagen equation proportional to resistance to the exponent 4: laminar & turbulent flow of blood. Small portion of the blood (closest to the wall) moves very slowly; as you move inward toward the centre, the velocity increases so that the blood in the middle layer will flow with the greatest speed. When flow velocity increases to a certain point, the flow will become turbulent.