PHSL 232 - LECTURE 7

Describe where areteries carry blood

away from the heart

describe where capillaries carry blood

tissues

describe where veins carry blood

to the heart

what are the two ciruclation systems

• systemic circulation

• pulmonary circulation

describe the route that blood takes in systemic circulation (beginning in the left atrium)

• oxygenated blood enters through the left atrium, goes into the ventricle

• gets ejected into the aorta

• into the artereis

• into the arterioles

• into the capilaries

• exchange occurs

• deoxygenated blood flows out of the capillary bed into the venules

• into the veins

• into the vena cava

• deoxygenated blood enters through the right atrium and into the right ventricle

describe the route that blood takes through the pulmonary circulation (starting at the right atrium)

• deoxygenated blood enters through the right atrium

• goes into the right ventricle

• out through the pulmonary artery to the arterioles

• to the capillary bed where it gets oxygenated

• to the venules and then the pulmonary vein

• then oxygenated blood enters through the left atrium

describe the difference in how cardiac output is distributed in systemic vs pulmonary circulation

• systemic circulation needs to reach all of thte tissues simultaneously, and so cardiac ouput is dividied

• pulmonary circulation only goes to the lungs and so cardiac ouput is undivided

what is blood flow determined by

• pressure gradient

• resistance

• Q=deltaP/R

what is resistance dependant on

• diameter

• the larger the diameter the lower the resistamce > higher flow

• the smaller the diameter the higher rhe reisstance > higher flow

what is poiseuille’s law

R=8ln/(pi)r^4

l is length

n is viscosity

r is radius

what do the walls of all types of blood vessels contain

• endothelium

which of the following decrease blood flow: increasing pressure gradient, reducing blood viscosity, reducing blood vessel radius, decreasing blood vessel resistance

• reducing the blood vessel radius

whcih vessel type has the most smooth muscle

• arteriole

which vessel type has the most elastic tissue

artery

which vessel type has the thinnest wall

capillary

which vessel type has the largest cross sectional area

• capillaries

which vessel type has the highest pressure

arteries

which vessel type has the slowest velocity

• capillaries

which vessel type has the biggest blood volume

veins

which vessel dampens pulsatile flow

arterioles

why does the venous sytem have less branching compared to capillaries

• because theyre going towards the heart and we have less branching of vessels, they kinda tend to come together to one source

which vessel type has the lowest pressure

veins