Chapter 21 Flashcards
elastic arteries are
pressure reservoirs and conducting arteries
vaso vasorum (what/where)
small vessels that supply blood to the tissues of the vessel and are is on the tunica externa
anastomosis
The union of the branches of two or more arteries supplying the same
body region
metarteriole
terminal end of the arteriole
arterioles known as
resistance vessels
microcirculation
The flow of blood from a metarteriole through capillaries and
into a postcapillary venule
capillaries known as
exchange vessels
capillary bed
a network of 10–100 capillaries that arises from a single metarteriole
thoroughfare channel
provides a direct route for
blood from an arteriole to a venule, thus bypassing capillaries
continuous capillaries vs fenestrated capillaries vs and sinusoids (what/where)
continuous tube with intracellular clefts; CNS, lungs, muscle tissue, skin
vs
have fenestrations; kidneys, villi of the SI, choroid plexuses of the ventricles in the brain, ciliary processes of the eyes, and most endocrine glands
vs
wider/windier, incomplete/absent basement membrane and large intracellular clefts; sinusoids of red bone marrow, spleen, anterior pituitary, parathyroid/adrenal glands
Usually blood passes from the heart and then in sequence through arteries, arterioles, capillaries, venules, and veins and then back to the heart. In some parts of the body, however, blood passes from one capillary network into another through a vein called a ______ vein. Such a circulation of blood is called a ____ _____
portal
portal system
BV increase of _____ have been measured in postcapillary and muscular venules
360%
Veins lack the internal or external ______ ______ found in arteries
elastic laminae
vascular sinus
vein with a thin endothelial wall that has no smooth muscle to alter its diameter
anastomotic veins
Some veins are paired and accompany medium to small-sized muscular arteries. These double sets of veins escort the arteries and connect via venous channels called anastomotic veins
The largest portion of your blood volume at rest, about ___, is in
systemic veins and venules so they function as _____ ______
64%
blood reservoirs
diffusions: capillary exchange method (importance, water/lipid soluble passes how/ex, what doesnt pass)
most important
water-soluble: pass through intracellular clefts/fenestrations (glucose/AA)
lipid soluble: directly through lipid bilayer of endothelial cell PM (O2, CO2, steroid hormones)
plasma proteins/RBCs cant pass unless its a sinusoid with large fenestrations
transcytosis: capillary exchange method (mainly for what/ex)
mainly for large, lipid-insoluble
molecules that cannot cross capillary walls in any other way (insulin/antibodies)
bulk flow: capillary exchange method (what for/how)
passive process in which large numbers of ions, molecules, or particles in a fluid move together in the same direction from higher to lower pressure
Diffusion is more important for _____ ____ between blood and interstitial fluid, but bulk flow is more important for regulation of the _____ _____ of blood and interstitial fluid.
solute exchange
relative volumes
Starling’s law of the capillaries
Overall, the volume of fluid and solutes reabsorbed normally is almost as large as the volume filtered
blood hydrostatic pressure (BHP) (number/due to/result)
35mmHg at arterial end of capillar, 16mmHG at venous end of capillary
due to the pressure that water in blood plasma exerts against blood vessel walls
“pushes” fluid out of capillaries into interstitial fluid
interstitial fluid hydrostatic pressure (IFHP)
0mmHg along capillaries
“pushes” fluid from interstitial spaces back into capillaries
Blood colloid osmotic pressure (BCOP) (number, caused by, result)
26 mmHg in most capillaries
caused by the colloidal suspension of these large proteins in plasma
“pull” fluid from interstitial spaces into capillaries
interstitial fluid osmotic pressure (IFOP)
0.1-5 mmHg
“pulls” fluid out of capillaries into interstitial fluid.
Thus, at the arterial end of a capillary, there is a net outward pressure
of ___ mmHg, and fluid moves out of the ______ into _____ _____ (filtration)
10
capillary
interstitial spaces
At the venous end of a capillary, the negative value (___ mmHg) represents a net inward pressure, and fluid moves into the _____ from tissue spaces (reabsorption)
-9
capillary
Blood flows from regions of _____ pressure to regions of _____ pressure; the greater the pressure difference, the _____ the blood flow. But the higher the resistance, the _____ the blood flow.
higher
lower
greater
smaller
in a resting, young adult, BP
rises to about ___ mmHg during systole (ventricular contraction) and
drops to about ___ mmHg during diastole (ventricular relaxation)
110
70
mean arterial pressure (MAP) (what/equation)
roughly 1/3 of the way between systolic/diastolic pressure
MAP= D BP + 1/3(S BP-D BP)
vascular resistance (what, 3 things it depends on)
the opposition to blood flow due to friction between blood and the walls of BV.
1. size of the blood vessel lumen
2. blood viscosity
3. total blood vessel length
respiratory pump
breathe in = blood to heart as thoracic cavity is decompressed and abdominal cavity is compressed due to diaphragm moving down
Systemic vascular resistance (SVR), AKA total peripheral resistance (TPR) (what, where is the regulator in brain)
refers to all of the vascular resistances offered by systemic blood vessels
vasomotor center in the brain stem regulates SVR
Velocity is ______ where the total cross-sectional area is greatest
slowest
circulation time is normally
1 minute
R atrium ->pulmonary -> L atrium -> systemic (to foot) -> R atrium
carotid sinus reflex vs aortic reflex (regulate what, sensory axons to reach CV center)
what kind of reflexes they both fall under and how does it work
regulated BP in the brain; glossopharyngeal (IX) nerves
vs
regulates systemic blood pressure vagus (X) nerves
baroreceptor reflexes (pressure)
lower pressure = lower impulse = decrease Psymp/increase symp = higher HR/BP and vice versa
Renin–angiotensin–aldosterone (RAA) system regulation of BP
BV falls = juxtaglomerular secrete renin = (1) release angiotensin II -> vasoconstriction and (2) release aldosterone -> reabsorb Na = increase BV/BP
chemoreceptor reflexes (where, detect and how they fix)
close to the baroreceptors of the carotid sinus (carotid bodies)and arch of the aorta (aortic bodies)
detect hypoxia, acidosis, hypercapnia = impulses to CV = increased symp = vasoconstriction and vice versa
Cardiovascular center (CV) location
medulla oblongata
epinephrine and norepinephrine regulation of BP
symp stimulation = adrenal medulla release E/NE = increase CO + vasoconstriction to exercising muscles
Antidiuretic hormone (ADH) regulation of BP
produced by hypot, release by ant pit in response to dehydration/ decreased BV = vasoconstriction, increase BV/decrease urine output
Atrial natriuretic peptide (ANP) regulation of BP
released by atrial cells = vasodilation, promote water/salt loss = decrease BV/BP
myogenic response
smooth muscle in arteriole walls
exhibits a myogenic response; it contracts more forcefully when it is stretched and relaxes when stretching lessens
The walls of blood vessels in the systemic circulation ____ in response
to low O2 = O2 delivery ______, which restores the normal O2 level. By contrast, the walls of blood vessels in the pulmonary circulation ______ in response to low levels of O2. This response ensures that blood mostly bypasses those alveoli (air sacs) in the
lungs that are poorly ventilated by fresh air. Thus, most blood flows to
better-ventilated areas of the lung.
dilate
increases
constrict
pulse normally
70-80 bpm at rest
systolic vs diastolic BP
When the cuff is deflated enough to allow the artery to open, a spurt of blood passes through= first sound
vs
cuff is deflated further, the sounds suddenly become too faint to be heard through the stethoscope = last sound
Korotkoff sounds
various sounds that are heard while taking blood pressure
The difference between systolic and diastolic pressure is called _____ pressure. This pressure is normally about ___ mmHg
pulse
40
hypovolemic shock vs cardiogenic shock vs vascular shock vs obstructive shock (what/ex)
due to decreased blood volume (hemorrhage)
vs
due to poor heart function (myocardial infarction)
vs
due to inappropriate vasodilation (anaphylactic, neurogenic, septic)
vs
due to obstruction of blood flow (pulmonary embolism)
responses to shock (4)
activation of RAA system
Secretion of ADH
activation of symp ANS
release of loval vasodilators
four divisions of aorta
ascending aorta
arch of the aorta
thoracic aorta
abdominal aorta
what does aorta divide into where/supplies
two common iliac arteries at 4 L vertebrae supplying pelvis and lower limbs
ascending aorta has ____ that supply the
R/L coronary arteries
branches to the atrial and ventricular myocardium (supplying heart)
3 major arteries from arch of aorta
brachiocephalic trunk
left common carotid
left subclavian
axillary and brachial artery come from (differrent)
Continuation of right subclavian artery and Continuation of axillary artery
thoracic artery begins/ends (and on what side of VC)
begins: at intervertebral disc between 4-5 T vertebrae, L to VC
ends: aortic hiatus (opening of the diaphragm between 12T/1L vert, ant to VC
what arises from anterior abdominal aortic and lateral aortic (3 each and if paired/unpaired)
celiac trunk, sup/inf mesenteric arteries (unpaired)
vs
suprarenal, renal, gonadal (paired)
how L/R common iliac arteries divide (4 divisions)
internal/external iliac arteries -> femoral arteries -> popliteal arteries -> ant/post tibial arteries
coronary sinus
receives blood from the cardiac veins that drain the heart
what are the 3 systemic veins
coronary sinus, sup/inf vena cava
what drains head/neck
internal/external jugular veins
deep veins (3) and superficial veins (2). of upper limbs
subcalivan, axillary, brachial
cephalic, basilic
inferior vena cava does not receive veins directly from the _____ ____, _____, _____, and _____ . These organs pass their blood into a common vein, the ______ ______ _____, which delivers the blood to the _____
GI tract
spleen
pancreas
gallbladder
hepatic portal vein
liver
A vein that carries blood from one capillary network to another is called a ______ vein
portal
The ______ ______ and ______ veins unite to form the hepatic portal vein
superior mesenteric
splenic
Veins consist of the same three tunics as arteries but have a thinner tunica
_____ and a thinner tunica ____
interna
media
cardiac output equals the ____ _____ ____ divided by total _______
mean arterial pressure
resistance
(CO = MAP ÷ R)
as blood leaves the aorta and flows through the systemic circulation, its
pressure progressively falls to ___ mmHg by the time it reaches the right ventricle.
0
The cardiovascular (CV) center is a group of neurons in the medulla oblongata that regulates _____ ____, ______, and _____ _____ _____
heart rate
contractility
blood vessel diameter
Output from the CV center flows along sympathetic and parasympathetic axons. Sympathetic impulses propagated along ________ nerves ______ heart rate and contractility; parasympathetic impulses
propagated along ______ nerves ______ heart rate
cardioaccelerator
increase
vagus
decrease
_____ is an abnormal increase in interstitial fluid.
Edema
