Dani - ch 14, 15 Flashcards
blood vessels of the body form a ____ loop system that begins and ends at the ___
closed
heart
everything but capillaries, all BV walls have __ layers
3
3 layers of blood vessel walls are called ___
tunics
___ is the inner channel within the blood vessel tubing that contains the blood
lumen
where blood is actually contained in a blood vessel
lumen
tunica ____: contains the endothelium that lines the lumen
intima
tunica intima: forms a slick surface that ___ friction
minimizes
tunica ___: circularly arranged smooth muscle and layers of elastic fibers
media
tunica media: regulates ___ and ___ of vessels and usually is the ___
vasoconstriction
vasodilation
thickest
tunica ___: mainly collagen fibers that protect and reinforce the vessel
externa
tunica externa: contains ___ fibers, ___ vessels, and tiny blood vessels called ___ ____ to nourish the external tissues of the blood vessels
nerve
lymphatic
vasa vasorum
blood circulation divided into 2 circulations
peripheral circulation
pulmonary circulation
peripheral circulation: blood flow to all tissues in the body except the ___
lungs
arteries carry ___ blood and veins carry ___ blood
oxygenated
deoxygenated
pulmonary circulation: blood flow through the ___ to exchange ___ for ___
lungs
CO2
O2
pulmonary arteries carry ___ blood and pulmonary veins carry ____ blood
deoxygenated
oxygenated
___ are the largest and most elastic vessels on the arterial side to move blood away from the heart under high pressure
arteries
high pressure in the arteries to ___ blood
deliver
arteries branch down into smaller ____
arterioles
blood pressure ___ rapidly into the arterioles from the arteries
decreases
arterioles have strong ___ walls so are able to ____ and ___ in response to tissue needs
muscular
vasocontrict
vasodilate
arterioles branch down to ___
capillaries
capillaries are the ___ vessels, the walls are __ cell thick
thinnest
one
pressure is __ in the capillaries so that ___ and __ exchange can occur
decreased
gas
nutrients
capillaries branch to ___ which branch to ___
venules
veins
there is ___ pressure in the veins so the walls are ___ but the lumen is ___
little
thinner
larger
the larger lumen allows the veins to serve as a ____ for blood
reservoir
veins are highly ____ so can expand and contract
expandable
pulmonary circulation contains ___% of the bodies blood
16
heart contains ___% of the bodies blood
7
lungs contains ___% of the bodies blood
9
systemic system contains ___% of the bodies blood
84
arteries contains ___% of the bodies blood
13
arterioles and capillaries contains ___% of the bodies blood
7
venules and veins contains ___% of the bodies blood
64
arteries are ___ reservoir
pressure
arterioles resistance vessels that control blood ___
distribution
capillaries are ___ sites
exchange
venules and veins are blood _____
reservoirs
____ ___: moving from high pressure to low pressure
pressure gradient
__ ___: the volume of blood flowing though the vessels, organs or the entire system in a given period
blood flow
tissues regulate blood flow based on ___
need
___ ___: blood flows at a steady stream though a smooth vessel because each layer of blood remains the same distance from the vessel wall
laminar flow
laminar flow - blood in the center flows ___ than outer layers
faster
laminar flow exhibits a ___ profile
parabolic
___ ___: occurs when blood flow is fast and/or the blood passes over a rough surface or an obstruction.
turbulent flow
turbulent flow means that blood begins forming ___ reulting in eddy currents
whorls
___ __ = force per unit area exerted on the vessel wall by the contained blood
blood pressure
blood pressure is measured in ____
mmHg
arterial pressure fluctuates between ___mmHg (SBP) and ___mmHg (DBP)
120
80
capillary pressure ranges from a high of ___mmHg on the arteriole side and __mmHg on the venule side
35
15
___: the opposition of flow
resistance
resistance is a measure of the ___ blood encounters as it passes through the vessels
friction
most friction is encountered in vessels (arteries and arterioles) away from the heart = ____ resistance
peripheral
resistance of the entire systemic circulation = ___ ___ resistance
total peripheral
the longer the vessel, the ___ the resistance
GREATER
if diameter is equal, if you double the length, you ___ the resistance
double
length increases while you ___
grow
largest change to resistance to flow occurs in the _____; where the muscle layer can change the diameter to ___ or ___
arteriole
vasodilate
vasocontrict
change in blood vessel diameter is based on the ___ ___ law
fourth power
fourth power law: diameter of a vessel doubles, flow does not double, it increases by the power of ___
four
parallel blood vessels are ____ in diameter, the vessels are ____ and not much muscle so resistance is ___ thus flow is ___
smaller
smoother
lower
fast
parallel blood vessels ___ total peripheral resistance
LOWER
___ ___: resistance to flow is affected by the thickness of blood (viscosity)
blood viscosity
normal blood is ___-___ times the viscosity of water
3-4
the more viscous the blood, the more ___ to flow
resistance
blood is made up of two major components
plasma
formed elements
__: the percentage of blood made up of RBCs
hematocrit
blood viscosity is fairly constant but conditions like ___ and ____ can affect viscosity which affects ____ to flow
anemia
polycythemia
resistance
ohm’s law:
- blood flow is ___ proportional to the difference between two points of blood pressure in circulation
directly
blood flow is ___ proportional to peripheral resistance
inversely
ohm’s formula
F = ___/___
difference in pressure/resistance
resistance has ___ of an effect on flow than difference in pressure
MORE
____: the ability of a blood vessel to become stretch, expanded, or dilated due to an internal pressure
distensability
the blood vessels are able to dilate because of layers of ___ between the layers of smooth muscles
elastin
the wall of the arteries are able to stretch but they are much ___ than the walls of veins
stronger
the wall of veins are ___ times ___ distensible than the walls of the arteries
8
moer
___: deals with the ability to stretch and the total quantity of blood that can be stored in a given vessel for each mmHg of pressure
compliance
compliance = ____ x ____
distensability x volume
systolic and diastolic blood pressure are measured in the ___ artery
brachial
___ ___: difference between systolic and diastolic blood pressure
pulse pressure
pulse pressure reflects ___
compliance
- distensibility
- volume
___ ___ ___: meaurement that reflects the pressure that propels the blood to the times
mean arterial pressure
more time is spent in diastole so the mid point between SBP and DBP is closer to the ___ BP
diastolic
during low or moderate exercise, MAP is the ___
midpoint
high intensity exercise, MAP is closer to ___ BP
systolic
___% of all blood volume is in the venous side of circulation at rest
64
when blood is lost and arterial pressure begins so fall, pressure sensitive areas of circulation signal the CNS to release hormones via the ___ NS which signal the veins to ____
SP
constrict
with __-__% of blood lost, the circulatory system functions ___
20-25
normally
___ ___: every time a person takes a step, a certain amount of blood is pumped back to the heart
venous pump
skeletal muscles surrounding the deep veins push blood upward and one way valves prevent ___
backflow
____ ___: when the valves in the venous system become incompetent
varicose veins
varicose veins: veins can be overstretched by excessive venous pressures such as during ___
pregnancy
varicose veins: cross-sectional area of the vein increases but the valves do not increase in size so the ___ do not close the vein off completely
leaflet
