Chapter 21 Blood Vessels and Circulation

arteries

carry blow away from the heart toward capillaries, where exchange between the blood and interstitial fluid occurs

cappillaries

site of exchange with tissues

veins

carry blood from the capillaries toward the heart

blood pressure (BP)

a measure of the force of blood pushing against the blood vessel wall, causes movement of blood through vessels

BP measurment

by listening for Korotkoff sounds produced by turbulent flow in arteries as pressure is released from a blood pressure cuff

BP resistance

the sum of all factors that oppose blood flow, increase when vessels become smaller and viscosity increases

vBP viscosity

the resistance of a fluid to flow, primarily from RBC, increases with dehydration

BF through a vessel

amount of blood that moves through a vessel in a given period of time, directly proportional to pressure difference and inversely proportional to resistance

diameter and BF

as diameter decreases, cross-sectional areas increase, and velocity of BF decreases (rapid through small, aorta, slow through broad, capillaries)

BP in aorta

100 mm Hg

BP in right atrium

0 mm Hg

filtration

moves materials out of capillaries

osmosis

moves materials into capillaries

venoud return increase

vasoconstriction of veins

increase blood volume

skeletal muscle pump