BIOL 031 Lecture Notes - Lecture 16: Central Venous Pressure, Pressure-Gradient Force, Blood Pressure

• School: College of The Sequoias
• Department: Biology (BIOL)
• Course: BIOL 031
• Professor: trimble

Document Summary

Fluid moves into and out of capillaries by bulk flow based on pressure gradients. Movement from capillary into interstitial space = filtration. Movement from interstitial space into capillary = absorption: getting things into the capillary. Forces for bulk flow: hydrostatic and osmotic pressures. Hydrostatic pressure gradient = force due to fluid: drives water out of capillaries and into interstation. Osmotic pressure = osmotic force exerted on water by non permeating solutes: only non-permeating solute = proteins, osmotic pressure = osmotic force of proteins. Hydrostatic pressure gradient: arteriole end: 37 mm hg, filtration, venous end: 15 mm hg (less pressure, results in filtration of water out of capillaries. Osmotic pressure gradient: 25 mm hg, drives water into capillaries, constant. A volume reservoir: expand with little change in pressure, function as a blood reservoir, 60% of total blood volume in systematic veins at rest, can hold larger than artery, ex.