Exam 2 Info - Slides Contd Flashcards
blood vessels: delivery system of dynamic structures that begins and ends at heart
arteries: carry blood … heart; oxygenated except for … and …
capillaries: contact …; directly serve cellular needs
veins: carry blood … heart
away from; pulmonary circulation; umbilical vessels of fetus;
tissue cells;
toward
(structure of blood vessel walls) …: central blood-containing space
lumen
(structure of blood vessel walls) three wall layers in arteries and veins: …, …, and …
tunica intima; tunica media; tunica externa
(structure of blood vessel walls) capillaries: … with sparse …
endothelium; basal lamina
(tunics) tunica intima:
… lines lumen of all vessels –> continuous with .., slick surface reduces …
endothelium; endocardium; friction
(tunics) tunica intima:
… in vessels larger than 1 mm; connective tissue basement membrane
subendothelial layer
(tunics) tunica media:
… and sheets of …
sympathetic vasomotor nerve fibers control … and … of vessels –> influence blood .. and …
smooth muscle; elastin;
vasoconstriction; vasodilation;
flow; pressure
(tunics) tunica externa (tunica adventitia):
… protect and reinforce; anchor to surrounding structures
contains …, …
… of larger vessels nourishes external layer
collage fibers;
nerve fibers; lymphatic vessels;
vasa vasorum
vessels vary in …, …, …, …
length; diameter; wall thickness; tissue makeup
(arterial system: elastic arteries) large thick-walled arteries with … in all three tunics
… and its major branches
large lumen offers …
elastin;
aorta;
low-resistance
(arterial system: elastic arteries) inactive in …
act as … - expand and recoil as blood ejected from heart – smooth pressure downstream
vasoconstriction;
pressure reservoirs
(arterial system: muscular arteries) … to elastic arteries – deliver blood to …
thick … with more smooth muscle
active in …
distal; body organs;
tunica media;
vasoconstriction
(arterial system: arterioles) smallest arteries
lead to …
control flow into these regions via … and …
capillary beds; vasodilation; vasoconstriction
(capillaries) microscopic blood vessels
walls of thin tunica intima –> in smallest … forms entire circumference
… help stabilize their walls and control permeability
diameter allows only … to pass at a time
oen cel;
pericytes;
single RBC
(capillaries) in all tissues except for …, …, … and … of eye
cartilage; epithelia; cornea; lens
(capillaries) provide … to almost every cell
functions:
exchange of …, …, …, …, etc., between blood and interstitial fluid
direct access;
gases; nutrients; wastes; hormones;
(capillaries) three structural types:
…. capillaries
… capillaries
… capillaries (…)
continuous;
fenestrated;
sinusoid; sinusoids
(continuous capillaries) abundant in skin and muscles:
… connect endothelial cells
… allow passage of fluids and small solutes
tight junctions;
intercellular clefts
(continuous capillaries) continuous capillaries of brain unique:
tight junctions are …, forming …
complete; blood-brain barrier
(fenestrated capillaries) some endothelial cells contain … (…)
more … than continuous capillaries
pores; fenestrations;
permeable
(fenestrated capillaries) function in … or … formation (small intestines, endocrine glands, and kidneys)
absorption; filtrate
(sinusoid capillaries) fewer …; usually …; larger …; large …
tight junctions; fenestrated; intercellular clefts; lumens
(sinusoid capillaries) blood flow … — allows …
large molecules and blood cells pass between blood and surrounding tissues
sluggish; modification
(sinusoid capillaries) found only in the …, …, …, …
… in lining to destroy bacteria
liver; bone marrow; spleen; adrenal medulla;
macrophages
(capillary beds) microcirculation:
interwoven networks of capillaries between … and …
terminal arteriole –> …
arterioles; venules;
metarteriole
(capillary beds) microcirculation:
metarteriole continuous with … (intermediate between capillary and venule)
thoroughfare channel
(capillary beds) thoroughfare channel –> … that drains bed
postcapillary venule
(capillary beds) … (….-… channel): directly connects terminal arteriole and postcapillary venule
vascular shunt; metarteriole-thoroughfare
(capillary beds) …: 10 to 100 exchange vessels per capillary bed
branch off metarteriole or terminal arteriole
true capillaries
true capillaries normally branch from … and return to …
metarteriole; thoroughfare channel
… regulate blood flow into true capillaries – blood may go into true capillaries or to shunt
regulated by … and …
precapillary sphincters; local chemical conditions; vasomotor nerves
sphincters open – blood flows through …
sphincters closed - blood flows through … channel and bypasses true capillaries
true capillaries;
metarteriole-thoroughfare
(venules) formed when capillary beds … –> smallest postcapillary venules; very …; allow … and … into tissues
consist of … and a few …
unite;
porous; fluids; WBCs;
endothelium; pericytes
(venules) larger venules have one or two layers of
smooth muscle cells
(veins) formed when venules converge
have … walls, … lumens compared with corresponding arteries
blood pressure … than in arteries
thinner; larger;
lower
(veins) thin …; thick … of collagen fibers and elastic networks
called … (…); contain up to 65% of blood supply
tunica media; tunica externa;
capacitance vessels; blood reservoirs
(veins) adaptations ensure return of blood to heart despite low pressure:
large diameter lumens offer …
… prevent backflow of blood –> most abundant in veins of….
…: flattened veins with extremely thin walls (e.g. coronary sinus of the heart and dural sinuses of the brain)
little resistance;
venous valves; limbs;
venous sinuses
…: volume of blood flowing through vessel, organ, or entire circulation in given period
blood flow
blood flow:
measured as …
equivalent to … for entire vascular system
relatively … when at rest
varies widely through individual organs, based on needs
ml/min;
cardiac output;
constant
blood pressure:
… per … exerted on wall of blood vessel by blood
expressed in …
measured as … in large arteries near heart
force; unit area;
mm Hg;
systemic arterial BP
blood pressure:
… provides driving force that keeps blood moving from higher to lower pressure areas
pressure gradient
resistance (peripheral resistance): …
measure of amount of … blood encounters with vessel walls, generally in peripheral (…) circulation
opposition to flow; friction; systemic
three important sources of resistance:
blood …
total …
blood vessel …
viscosity;
blood vessel length;
diameter
(resistance) factors that remain relatively constant:
…: the “stickiness” of blood due to formed elements and plasma proteins
…
blood viscosity;
blood vessel length
(resistance) increased viscosity = … resistance
longer vessel = … encountered
increased; greater resistance
(resistance) … is greatest influence on resistance
frequent changes alter …
varies inversely with … of vessel radius
blood vessel diameter;
peripheral resistance;
fourth power
(resistance) … major determinants of peripheral resistance
small-diameter arterioles
(resistance) abrupt changes in diameter or fatty plaques from … dramatically increase resistance –> disrupt … and cause …
… equals increased resistance
atherosclerosis;
laminar flow; turbulent flow;
irregular fluid motion
(resistance) blood flow (F) directly proportional to …
if this latter variable increases, blood flow …
pressure gradient (delta P); speeds up
(resistance) blood flow inversely proportional to …
if the latter variable increases, blood flow …
F = …
peripheral resistance; decreases;
delta P/ R
(resistance) R more important in influencing local blood flow because easily changed by altering …
blood vessel diameter
systemic blood pressure:
… of heart generates blood flow
pressure results when flow is …
pumping action;
opposed by resistance
systemic blood pressure: highest in ... ... throughout pathway 0 mm Hg in ... steepest drop occurs in ...
aorta;
declines;
right atrium;
arterioles
arterial blood pressure: reflects two factors of arteries close to heart: ... (.../...) ... forced into them at any time blood pressure near heart is ...
elasticity; compliance; distensibility;
volume of blood;
pulsatile
arterial blood pressure:
systolic pressure: pressure exerted in … during …
averages … mm Hg in normal adult
aorta; ventricular contraction; 120
arterial blood pressure:
…: lowest level of aortic pressure
diastolic pressure
arterial blood pressure:
… = difference between systolic and diastolic pressure
throbbing of arteries (…)
pulse pressure;
pulse
arterial blood pressure:
….: pressure that propels blood to tissues
mean arterial pressure (MAP)
arterial blood pressure:
MAP = … + …
pulse pressure and MAP both … with increasing distance from heart
diastolic pressure; 1/3 pulse pressure;
decline
capillary blood pressure:
ranges from … to … mm Hg
low capillary pressure is desirable:
high BP would … fragile, thin-walled capillaries
most very permeable, so low pressure forces filtrate into …
17; 35;
rupture;
interstitial spaces
venous blood pressure:
changes … during cardiac cycle
small pressure gradient: about … mm Hg
low pressure due to cumulative effects of …
energy of blood pressure lost as … during each circuit
little;
15;
peripheral resistance;
heat
(factors aiding venous return) …: contraction of skeletal muscles “milks” blood toward heart; valves prevent …
….: pressure changes during breathing move blood toward heart by squeezing … as thoracic veins expand
…. under sympathetic control pushes blood toward heart
muscular pump; backflow;
respiratory pump; abdominal veins
venoconstriction;
maintaining blood pressure:
requires cooperation of …, …, and … and supervision by …
heart; blood vessels; kidneys; brain
main factors influencing blood pressure:
…
…
…
cardiac output (CO); peripheral resistance (PR); blood volume
maintaining blood pressure:
F = …
CO = …
delta P = …
delta P/R;
delta P/R;
CO * R
maintaining blood pressure:
blood pressure = …
blood pressure varies directly with …, …, and …
changes in one variable quickly compensated for by changes in other variables
CO * PR (peripheral resistance);
CO; PR; blood volume
(cardiac output) CO = …
normal: … - … L/min
SV (stroke volume); HR (heart rate)
5-5.5
(cardiac output) determined by …, and … and … controls
venous return; neural; hormonal
(cardiac output) resting heart rate maintained by … via …
cardioinhibitory center; parasympathetic vagus nerves
(cardiac output) stroke volume controlled by
venous return
(cardiac output) during stress, cardioacceleratory center increases … and … via … stimulation
… increases
heart rate; stroke volume; sympathetic stimulation;
MAP
(control of blood pressure) short term … and … controls:
counteract fluctuations in blood pressure by altering peripheral resistance and CO
long term … regulation: counteracts fluctuations in blood pressure by altering blood volume
neural; hormonal; renal
(control of blood pressure) neural controls of peripheral resistance:
maintain MAP by altering … –> if low blood volume all vessels … except those to heart and brain
alter … to organs in response to specific demands
blood vessel diameter;
constricted;
blood distribution
(control of blood pressure) neural controls operate via ... that involve: ... cardiovascular center of ... ... to heart and vascular smooth muscle sometimes input from ... and higher ...
reflex arcs; baroreceptors; medulla; vasomotor fibers; chemoreceptors; brain centers
(cardiovascular center)
clusters of sympathetic neurons in medulla oversee changes in … and …
consists of … and …
CO; blood vessel diameter;
cardiac centers; vasomotor center
(cardiovascular center)
vasomotor center sends steady impulses via … to blood vessels –> moderate constriction called …
receives inputs from …, …, and …
sympathetic efferents; vasomotor tone;
baroreceptors; chemoreceptors; higher brain centers
baroreceptors located in:
…
…
walls of large arteries of … and …
carotid sinuses;
aortic arch;
neck; thorax
increased blood pressure stimulates baroreceptors to … to …
inhibits … and … centers, causing arteriole dilation and venodilation
stimulates … center –> decreased blood pressure
increase input; vasomotor center;
vasomotor; cardioacceleratory;
cardioinhibitory
decrease in blood pressure due to:
…
…
decreased …
arteriolar vasodilation;
venodilation;
cardiac output
if MAP low:
reflex … –> increased … –> increased …
ex. upon standing baroreceptors of … reflex protect blood to brain; in systemic circuit as whole … reflex maintains blood pressure
vasoconstriction; CO; blood pressure;
carotid sinus;
aortic
baroreceptors … if altered blood pressure sustained
ineffective
… in aortic arch and large arteries of neck detect increase in …, or drop in … or …
chemoreceptors; CO2; pH; O2
chemorceptors cause increased blood pressure by:
signaling … –> increase …
signaling … –> increase …
cardioacceleratory center; CO;
vasomotor center; vasoconstriction
influences of higher brain centers in maintaining BP:
reflexes in …
… and … can modify arterial pressure via relays to medulla
medulla;
hypothalamus; cerebral cortex
influences of higher brain centers in maintaining BP:
… increases blood pressure during stress
hypothalamus mediates … during exercise and changes in …
hypothalamus;
redistribution of blood flow; body temperature
influences of hormonal controls in maintaining BP:
short term regulation via changes in …
long term regulation via changes in ..
peripheral resistance; blood volume
influences of hormonal controls in maintaining BP:
cause increased blood pressure:
… and … from adrenal gland –> increased … and …
… stimulates vasoconstriction
high … levels cause vasoconstriction
epi; norepi;
CO; vasoconstriction;
angiotensin II;
ADH
influences of hormonal controls in maintaining BP:
cause lowered blood pressure:
… causes decreased blood volume by antagonizing …
atrial natriuretic peptide; aldosterone
influences of renal reg in maintaining BP:
baroreceptors quickly adapt to chronic high or low BP so are ineffective
long term mechanisms control BP by altering … via …
blood volume; kidneys
influences of renal reg in maintaining BP:
kidneys regulate arterial blood pressure:
… renal mechanism
… renal (…) mechanism
direct;
indirect; renin-angiotensin-aldosterone
direct renal mechanism
alters blood volume … of hormones:
increased BP or blood volume causes …, thus reducing BP
decreased BP/blood volume causes kidneys to …, and BP rises
also there is less … by the kidneys
independently; elimination of more urine; conserve water; filtration
indirect renal mechanism:
the renin-angiotensin-aldosterone mechanism:
decreased arterial blood pressure leads to release of ..,. which catalyzes conversion of … from liver to ..
renin;
angiotensinogen; angiotensin I
indirect renal mechanism:
angiotensin converting enzyme, esp from lungs, converts … to …
angiotensin I; angiotensin II
(functions of angiotensin II) … blood volume:
stimulates … secretion
causes … release
triggers … center
increases;
aldosterone;
ADH;
hypothalamic thirst
(functions of angiotensin II) causes … directly increasing blood pressure – increased peripheral resistance
vasoconstriction
(heart anatomy) approximately the size of
a fist
(heart anatomy) location:
in the … between second rib and fifth intercostal space
on the superior surface of …
two thirds to the left of the …
anterior to the …, posterior to the …
mediastinum; diaphragm; midsternal line; vertebral column; sternum
(heart anatomy) heart is enclosed in …, a double walled sac
pericardium
(pericardium) superficial …: protects, anchors, and prevents overfilling
fibrous pericardium
(pericardium) deep two-layered …:
… layer lines the internal surface of the fibrous pericardium
… layer(…) on external surface of the heart
separated by … (decreases friction)
serous pericardium;
parietal;
visceral; epicardium;
fluid-filled pericardial cavity
(3 layers of the heart wall) …: visceral layer of the serous pericardium
epicardium
(3 layers of the heart wall) …: spiral bundles of cardiac muscle cells
… of the heart: crisscrossing, interlacing layer of connective tissue
anchors …
supports … and …
limits … to specific paths
myocardium; fibrous skeleton; cardiac muscle fibers; great vessels; valves; spread of action potentials
(3 layers of the heart wall) … is continuous with endothelial lining of blood vessels
endocardium
(chambers) four chambers:
two atria: separated internally by the …
… (…) encircles the junction of the atria and ventricles
interatrial septum;
coronary sulcus; atrioventricular groove
(chambers) two ventricles:
separated by the …
anterior and posterior … mark the position of the septum externally
interventricular septum;
interventricular sulci
(atria: the receiving chambers) walls are ridged by ... vessels entering right atrium: ... ... ...
pectinate muscles;
superior vena cava;
inferior vena cava;
coronary sinus
(atria: the receiving chambers) vessels entering left atrium:
right and left …
pulmonary veins
(ventricles: the discharging chambers
…. project into the ventricular cavities
vessel leaving the right ventricle: …
vessel leaving the left ventricle: …
papillary muscles;
pulmonary trunk;
aorta
(pathway of blood through the heart) the heart is two side by side pumps:
right side is the pump for the … circuit: vessels that carry blood to and from the …
left side is the pump for the …
vessels that carry the blood to and from all …
pulmonary; lungs;
systemic; body tissues
(pathway of blood through the heart) … are where gas exchange occurs
capillary beds
(pathway of blood through the heart) … to … to …
beginning of right side for this one
right atrium; tricuspid valve; right ventricle
(pathway of blood through the heart) continuation of right side for this one:
… to … to … to … to lungs
right ventricle; pulmonary semilunar valve; pulmonary trunk; pulmonary arteries
(pathway of blood through the heart) starting from lungs
lungs to … to …
pulmonary veins; left atrium
(pathway of blood through the heart) from left atrium to … to …
bicuspid valve; left ventricle
(pathway of blood through the heart) from left ventricle to … to … to …
aortic semilunar valve; aorta; systemic circulation
…: the functional blood supply to the heart muscle itself
coronary circulation
(coronary circulation) arterial supply varies considerably and contains many … (…) among branches
anastomoses; junctions
(coronary circulation) … routes provide additional routes for blood delivery
collateral
(coronary circulation) arteries:
… and … (in … groove), …, …, and anterior … arteries
right and left coronary; atrioventricular;
marginal;
circumflex;
interventricular
(coronary circulation) veins:
…
…
..
small cardiac;
anterior cardiac;
great cardiac
(homeostatic imbalances) angina pectoris: thoracic pain
caused by a fleeting deficiency in … to the …
cells are …
blood delivery; myocardium; weakened
(homeostatic imbalances) myocardial infarction (…):
prolonged …
areas of cell death are repaired with …
heart attack;
coronary blockage;
noncontractile scar tissue
(heart valves) ensure … blood flow through the heart
unidirectional
(heart valves) atrioventricular valves:
prevent backflow into the … when … contract
… valve (right)
… valve (left)
atria; ventricles;
tricuspid;
mitral
(heart valves) … anchor AV valve cusps to papillary muscles
chordae tendineae
(heart valves) semilunar (SL) valves:
prevent backflow into the … when … relax
… semilunar valve
… semilunar valve
ventricles; ventricles;
aortic;
pulmonary
(heart valves) 1. blood returning to the heart fills atria, putting pressure against … valves, which forces them open
- as ventricles fill, this valve flaps hang limply into ventricles
- atria …, forcing additional blood into ventricles
Atrioventricular;
contract
(heart valves) AV valves open; … pressure greater than … pressure
atrial; ventricular
(heart valves) 1. ventricles contract, forcing blood against …
- … valves close
- … contract and chordae tendieae tighten, preventing valve flops from everting into atria
atrioventricular valve cusps;
atrioventricular valves;
papillary muscles
(heart valves) AV valves closed; … pressure less than … pressure
atrial; ventricular
(heart valves) as ventricles contract and … pressure rises, blood is pushed up against … valves, forcing them open
as ventricles relax and … pressure falls, blood flows back from arteries, filling the … and forcing them to close
intraventricular; semilunar;
intraventricular; cusps of semilunar valves
(microscopic anatomy of cardiac muscle) cardiac muscle cells are …, …, …, …, and …
striated; short; fat; branched; interconnected
(microscopic anatomy of cardiac muscle) … (…) connects to the fibrous skeleton
connective tissue matrix; endomysium
(microscopic anatomy of cardiac muscle) T tubules are wide but less …; SR is … than in skeletal muscle
numerous large … (25-35% of cell volume)
numerous; simpler;
mito
(microscopic anatomy of cardiac muscle) …: junctions between cells anchor cardiac cells
… prevent cells from separating during contraction
… allow ions to pass; electrically couple adjacent cells
intercalated discs;
desmosomes;
gap junctions
(microscopic anatomy of cardiac muscle) heart muscle behaves as a …
functional syncytium
(indirect renal mechanism for renin-angiotensin-aldosterone) decreased arterial pressure leads to inhibition of … and increased … nervous system activity, followed by … release from the kidneys
baroreceptors;
sympathetic NS;
renin
(indirect renal mechanism for renin-angiotensin-aldosterone) angiotensin II activates adrenal cortex and leads to secretion of … which leads to increase of … and … reabsorption by the kidneys which leads to increase in … along with the water intake from hypothalamus, lead leads to increase in arterial pressure
aldosterone; sodium and water;
blood volume
(factors that increase MAP) increased activity of muscular pump and respiratory pump leads to increased … and increased … which increases … and thus increases mean arterial pressure
venous return; stroke volume; cardiac output
(factors that increase MAP) decreased release of ANP increases conservation of … and … by kidneys which increases blood volume which increases venous return which increases stroke volume which increases cardiac output
Na+; water;
(factors that increase MAP) fluid loss from …, excessive … leads to decreased blood volume and decreased blood pressure which activates … and activates … and … centers in brain stem which increases stroke volume, heart rate, and … of blood vessels
hemorrhage; sweating;
baroreceptors; vasomotor; cardioacceleratory; diameter
(factors that increase MAP)
increased …, …. (epinephrine, NE, ADH, angiotensin II)
vasomotor tone; bloodborne chemicals
(factors that increase MAP) …, and high … and increased …
dehydration; hematocrit; body size
