Nycc Systems Physiology Heart: Vascular Function And Blood Flow

Front 1

What are the atrial and ventricular syncytiums?

Back 1

Networks of cardiac muscle cells connected by intercalated discs that aid in coordinated contraction

Front 2

What are the specialized excitatory and conductive muscle fibers of the heart?

Back 2

Sinuatrial (S-A) nodal fibers, Atrioventricular (A-V) nodal fibers, A-V bundle

Front 3

What is the Frank-Starling mechanism?

Back 3

Within physiologic limits, the heart pumps all of the blood that returns to it by the way of veins

Front 4

Cardiac output = ___ x ___

Back 4

Heart rate (HR); Stroke volume (SV)

Front 5

Stroke volume = End-_____ volume - End-_____ volume.

Back 5

Diastolic; Systolic

Front 6

At the end of diastole, the heart is finished _____.

Back 6

Filling

Front 7

At the end of systole, the heart is finished _____.

Back 7

Emptying

Front 8

If the end-diastolic volume is 120 ml and the end-systolic volume is 50 ml, what are the stroke volume and ejection fraction?

Back 8

SV = 70 ml, EF = 60%

(EF = 70/120)

Front 9

Cardiac output = __ beats/min x __ ml/beat = _____ ml/min.

Back 9

72; 70; 5040

Front 10

At rest, the heart pumps __-__ L/min of blood.

Back 10

5-6

Front 11

The heart is controlled by _____ and _____ nerves.

Back 11

Sympathetic; Parasympathetic

Front 12

Cardiac muscle has _____ and _____ filaments and _____ resistance _____ disks (_____ the resistance of cell membrane.)

Back 12

Actin; Myosin; Low; Intercalated; 1/400

Front 13

Cardiac muscle has _____ _____ network per _____ located at the level of the _____.

Back 13

One T-tubule; Sarcomere; Z disc

Front 14

Skeletal muscle has _____ _____ networks per _____ located near the ends of the _____ filaments at the _____ band junctions.

Back 14

Two T-tubule; Sarcomere; Myosin; A-I

Front 15

Smooth muscle has _____, but no _____, _____, _____ or _____.

Back 15

Caveoli; T-tubules; Troponin (calmodulin); Tropomyosin

Front 16

What are caveoli?

Back 16

Specialized invaginations in smooth muscle

Front 17

Resting membrane potential of cardiac muscle is ___ to ___ millivolts.

Back 17

-85 to -95

Front 18

Action potential of cardiac muscle is ___ milivolts with an upstroke of +___ millivolts

Back 18

105; 20

Front 19

Plateau lasts ~___-___ seconds in ventricular muscle (much longer than _____ muscle)

Back 19

0.2-0.3; Skeletal

Front 20

Ventricular muscle action potential phases:
0: Fast ___ channels open then slow ___ channels open
1: ___ channels open
2: ___ channels open more
3: ___ channels open more
4: _____ _____ potential

Back 20

Na+; Ca++; K+; Ca++; K+; Resting membrane

Front 21

During the refractory period, cardiac muscle cannot be _____.

Back 21

Re-excited

Front 22

The refractory period lasts ___-___ seconds in the ventricles.

Back 22

0.25-0.30

Front 23

The refractory period lasts ___ seconds in the atria.

Back 23

0.15

Front 24

Ca++ is released from the _____ _____ and the _____ as a result of action potential.

Back 24

Sarcoplasmic reticulum; T-tubules

Front 25

As a result of the action potential, _____ Ca++ depends strongly on _____ Ca++ concentration.

Back 25

T-tubule; Extracellular

Front 26

As a result of the action potential, _____ bind Ca++ for storage inside the _____.

Back 26

Mucopolysaccharides; T-tubules

Front 27

Is Ca++ defiency detectable by blood testing?

Back 27

No

Front 28

In excitation coupling:
1. The action potential: moves along the _____.
2. ___ receptors are activated.
3. ___ binds to the _____ receptor which opens releasing much ___.
4. Calcium is pumped back into the _____ _____ and back into the _____.
5. Contraction is _____.

Back 28

1. T-tubule
2. DHP
3. Ca; Ryanodine; Ca
4. Sarcoplasmic Reticulum; T-tubule
5. Terminated

Front 29

What is the major difference between excitation coupling in skeletal muscle and in cardiac muscle?

Back 29

Skeletal muscle sarcoplasmic reticulum release is triggered by Voltage.
Cardiac muscle sarcoplasmic reticulum release is triggered by Calcium.

Front 30

The sympathetic aspect of the ANS _____ heart rate from 72 bpm to ___-___ bpm.

Back 30

Increases, 180-200

Front 31

The sympathetic response of the ANS _____ force of heart contraction ___x normal.

Back 31

Increases, 2

Front 32

The sympathetic response of the ANS can _____ cardiac output by more than ___%.

Back 32

Increase, 100

Front 33

The parasympathetic (vagal; vasovagal) response of the ANS _____ heart rate from 72 bpm to ___-___ bpm.

Back 33

Decreases; 30-40

Front 34

The parasympathetic (vagal; vasovagal) response _____ force of heart contraction ___% to ___%

Back 34

Decreases; 20; 30

Front 35

The parasympathetic (vagal; vasovagal) response can _____ cardiac output by ___% or more.

Back 35

Decrease; 50%

Front 36

Sympathetic mechanism effects:
_____ release
Increased permeability of ___ & ___
_____ of S-A node, A-V node, A-V bundles
_____ of cardiac (ventricular) muscle
Increased permeability of _____ contributes to exciting the contractile process of _____ _____.

Back 36

Norepinephrine; Na+ & Ca++, Depolarization; Depolarization; Ca++; Cardiac myofibrils

Front 37

The main sympathetic effect mechanism is a(n) _____ in _____ _____.

Back 37

Increase; Contractile strength

Front 38

Parasympathetic mechanism effects:
Fiber distribution: _____ _____ and _____ _____.
_____ release
Increased permeability of ___.
Decreased rate of rhythm of _____ _____ fibers.
_____transmission of cardiac impulses into _____ from the _____ node (_____ factor)

Back 38

S-A node; A-V node; Acetylcholine; K+; S-A node; Slowed; Ventricles; A-V; Safety

Front 39

Parasympathetic effect mechanisms?
1. Decreased rate of rhythm of _____ node fibers
2. Slowed transmission of _____ node cardiac impulses into the ventricles

Back 39

SA; AV

Front 40

In _____ muscle, maximal active stress is developed at normal resting length; ~__ microns.

Back 40

Skeletal; 2

Front 41

Cardiac muscle normally operates at lengths ______ optimal length.

Back 41

Below

Front 42

Excess ___ decreases contractility and slows the heart rate.

Back 42

K+

Front 43

Excess ___ causes spastic contraction.

Back 43

Ca++

Front 44

Low ___ causes cardiac flaccidity.

Back 44

Ca++

Front 45

The _____ _____ is the series of mechanical events from the beginning of one heartbeat to the next.

Back 45

Cardiac cycle

Front 46

The cardiac cycle begins with _____ generation of a(n) _____ _____ in the ___ node that is propagated through the heart via the _____system.

Back 46

Spontaneous; Action potential; S-A; Conducting

Front 47

The _____ contract first and function as _____ _____ for the ventricles.

Back 47

Atria; Primer pumps

Front 48

What is the period of relaxation where the heart fills with blood?

Back 48

Diastole

Front 49

What is the period of contraction of the heart?

Back 49

Systole

Front 50

There are _____, _____, and _____ events associated with the cardiac cycle.

Back 50

Volume, Pressure, Electrical

Front 51

The ECG (EKG) monitors the _____ events that result in a _____ event (_____)

Back 51

Electrical; Mechanical; Contraction

Front 52

What does the P wave signify?

Back 52

Depolarization of the atria

Front 53

What does the QRS wave signify?

Back 53

Depolarization of the ventricles

Front 54

What does the T wave signify?

Back 54

Repolarization of the ventricles

Front 55

___% of blood returning to heart flows through _____ into ventricles prior to _____ contraction.

Back 55

80; Atria; Atrial

Front 56

_____ contraction causes the additional ___% of ventricle _____.

Back 56

Atrial; 20; Filling

Front 57

Under most conditions, the heart can operate without the 20% of blood added by _____ _____.

Back 57

Atrial contraction

Front 58

Atrial failure may not be noticed unless the patient _____; then acute signs of heart _____ may develop along with _____ of _____.

Back 58

Exercises, Failure, Shortness; Breath

Front 59

What does the a-wave signify?

Back 59

Atrial contraction

Front 60

What does the c-wave signify?

Back 60

Ventricular contraction; AV valve bulges as pressure increases in ventricle

Front 61

What does the v-wave signify?

Back 61

Slow flow of blood into atria while AV valves are closed

Front 62

The a-, c-, and v-waves are part of the _____ _____ _____.

Back 62

Atrial pressure curve.

Front 63

During ventricular diastole, ___ valves open and the _____ fill with blood.

Back 63

AV; Ventricles

Front 64

During the ___1/3 of ventricular diastole, the ventricles fill rapidly.

Back 64

First

Front 65

During the _____ 1/3 of ventricular diastole a small amount of blood flows into the ventricles; _____.

Back 65

Second; Diastasis

Front 66

During the _____ 1/3 of ventricular diastole the atria contract and fill ___% of ventricle volume.

Back 66

Third (Last); 20

Front 67

Cardiac cycle 1 - Ventricular systole begins:
_____ contraction begins
_____ pressure rises
_____ valves close
_____ and _____ valves open against pressure in aorta and pulmonary artery
_____ is occurring (_____ increasing) but no ventricular _____ has occured.

Back 67

Isovolumic; Ventricular ; AV; Aortic; Pulmonary; Contraction; Tension; Emptying

Front 68

Cardiac cycle 2 - Ejection phase:
_____ ventricular pressure > ___ mm Hg and _____ valves open
Blood pours out of _____ ; ___% in first ___ of ejection phase (_____ ejection)
Remaining ___% is ejected in last ___ of phase (___ ejection)

Back 68

Left; 80; Semilunar; Ventricles; 70; 1/3; Rapid; 30; 2/3; Slow

Front 69

Cardiac cycle 3 - End of systole:
_____ relax allowing _____ pressures to decrease rapidly.
Elevated _____ pressure pushes some blood back toward _____ closing _____ valves.
_____ continue to relax though ____ volume does not change (_____ relaxation)
_____ pressures decrease rapidly to their low _____ levels; _____ valves open and a new cycle begins.

Back 69

Ventricles; Intraventricular; Arterial; Ventricles; Semilunar; Ventricles; Ventricular; Isovolumic; Intraventricular; Diastolic; AV

Front 70

During diastole, ventricle volume rises to ~___ to ___ ml; the _____-_____ volume

Back 70

110; 120; End-diastolic

Front 71

As ventricles empty in systole, volume decreases about ___ml; the _____ volume.

Back 71

70; Stroke

Front 72

The remaining volume of the ventricles (40 - 50 ml) is the _____-_____ volume

Back 72

End-systolic

Front 73

The fraction of end-diastolic volume that is ejected is the _____ _____; usually ___% of total volume.

Back 73

Ejection fraction; 60

Front 74

_____ _____ volume minus _____ _____ volume = stroke volume

Back 74

End diastolic; End systolic

Front 75

(_____ volume / _____ _____ volume) = ejection fraction

Back 75

Stroke; End diastolic

Front 76

If the stroke volume is 70 ml and the heart rate (HR) is 70 beats/minute, what is the cardiac output?

Back 76

=HR x Stroke volume
=70/min x 70 ml
=4900 ml/min

Front 77

Cardiac cycle - Aortic pressure curve:
Pressure in the aorta _____ during systole after the _____ valve opens to ~ ___ mm Hg (systolic pressure)
_____ of arterial walls maintains pressure as the valve closes.
_____ (dicrotic notch occurs in the curve when the _____ valve closes. There is a short period of _____ of blood before closure of the valve, followed by cessation of _____.
Valves close and aortic pressure _____ slowly throughout diastole as blood stored in distended arteries flows into the periphery.
Before the _____ contracts again, aortic pressure usually falls to ~ ___ mm Hg (_____ pressure).

Back 77

Increases; Aortic; 120; Elasticity; Incisura; Aortic; Backflow; Backflow; Decreases; Ventricle; 80; Diastolic

Front 78

What causes the heart sounds?

Back 78

Valve closure and the resulting pressure changes

Front 79

What causes the first heart sound?

Back 79

Closure of the atrioventricular valves

(the "lub" of the "lub-dup")

Front 80

What causes the second heart sound?

Back 80

Closure of semilunar (aortic & pulmonary) valves

(the "dup" of the "lub-dup")

Front 81

What causes the third heart sound?

Back 81

Rapid filling of the ventricles

Front 82

What are the 3 determinants of myocardial performance for the left ventricle?

Back 82

Preload, Afterload, Contractility

Front 83

Preload is the _____ _____ volume; _____ _____ when the _____ ventricle begins contraction

Back 83

End diastolic (120 ml); Muscle tension; Left

Front 84

What is afterload?

Back 84

Aortic pressure

Front 85

What is contractility?

Back 85

(change in length / change in time)

Front 86

What is active myocardial length-tension (Frank-Starling) determined by?

Back 86

Overlapping of actin & myosin and shifts with changes in contractility

Front 87

Passive length-tension is due to _____ of _____ _____.

Back 87

Stretching; Cardiac tissue

Front 88

Increase in preload provides better _____-_____ overlap resulting in more _____ force.

Back 88

Actin-myosin; Contractile

Front 89

Afterload determines how much _____ is used to generate _____ and how much _____ is used for shortening.

Back 89

Force; Pressure; Force

Front 90

Changes in contractility provide a _____-independent mechanism to increase _____ force.

Back 90

Preload; Contractile

Front 91

Myocardial _____ enhances myocardial performance.

Back 91

Preload

Front 92

Increase in end-diastolic pressure (e.g., increased venous return) causes an increase in _____ _____ development and consequently increases _____ _____ of the heart.

Back 92

Ventricular pressure; Pumping ability

Front 93

What is the Frank-Starling law?

Back 93

Within physiological limits, the heart pumps all blood returned to it by the veins.

Front 94

Increasing initial fiber length causes more _____ _____, but does not increase _____.

Back 94

Forceful contraction; Contractility

Front 95

Afterload affects _____ and the onset of _____.

Back 95

Contractility; Shortening

Front 96

What is the major proportion of energy to move blood for low-pressure veins to the high-pressure arteries?

Back 96

Volume-pressure work (external work)

Front 97

What is the minor proportion of energy to accelerate blood to the ejection velocity through the valves?

Back 97

Kinetic energy of blood flow

Front 98

Volume-pressure curve - Period of filling:
Ventricle is in _____
Atrial pressure exceeds _____ pressure and AV (mitral) valve opens
_____ of blood in ventricle increases, atria _____ to add last ___% of volume
_____-_____ volume is reached

Back 98

Diastole; Ventricular; Volume; Contracts; 20; End-diastolic

Front 99

Volume-pressure curve - Isovolumic contraction:
_____ and _____ valves closed
_____ contracts; increasing pressure
Ventricular pressure exceeds _____ pressure and _____ valve opens (~ ___ mm Hg)

Back 99

AV; Aortic; Ventricle; Aortic; Aortic; 80

Front 100

Volume-pressure curve - Ejection:
_____ continues to contract
_____ pressure continues to increase
_____ decreases as blood is pushed into _____ (ejection fraction)
_____-_____ volume is reached; not all blood is pumped out of _____ (___ - ___ ml remain)

Back 100

Ventricle; Systolic; Volume; Aorta; End-systolic; Ventricle; 40 - 50

Front 101

Volume-pressure curve - Isovolumic relaxation:
_____ valve closes as _____ pressure falls below _____ pressure
Relaxation continues with no change in _____
_____ pressures fall below _____ pressure and AV valves _____; cycle begins again

Back 101

Aortic; Ventricular; Aortic; Volume; Ventricular; Atrial; Open

Front 102

For _____, preload is considered the _____-_____ volume when ventricles are filled.

Back 102

Contraction; End-diastolic

Front 103

Afterload of the _____ is the pressure in the _____.

Back 103

Ventricle; Aorta

Front 104

Increased _____ stimulation of the heart or cardiac _____ result in an increase in contractility.

Back 104

Sympathetic; Hypertrophication (e.g., from marathon training)

Front 105

What are the two basic means by which volume of blood pumped by the heart is regulated?

Back 105

Frank-Starling mechanism (intrinsic regulation), Control of heart rate and strength of pumping by the ANS (extrinsic regulation)

Front 106

The Frank-Starling mechanism describes the _____ ability of the heart to adapt to increasing _____ of inflowing blood.

Back 106

Intrinsic; Volumes

Front 107

The greater the heart is _____ during filling, the greater the force of _____ and _____ of blood pumped into the aorta.

Back 107

Stretched; Contraction; Volume

Front 108

What 3 things does sympathetic stimulation increase?

Back 108

Heart rate, Force of contraction (so increased volume of blood pumped and ejection pressure), Cardiac output

Front 109

What 3 things does parasympathetic stimulation decrease?

Back 109

Heart rate (b/c vagal fibers innervate the atria), Strength of heart muscle contraction, Ventricular pumping (b/c of first two)

Front 110

Changes in _____ _____ from _____ _____ _____ stimulation result from changes in heart rate and contractile strength of the heart.

Back 110

Cardiac output; Autonomic nervous system

Front 111

Intrinsic spontaneous rate of _____ _____ depolarization is dominated by _____ innervations from the _____ using _____ as a transmitter.

Back 111

Sinuatrial node; Parasympathetic; Vagus (CN X); ACh

Front 112

ACh slows _____ _____ _____ and lowers _____ _____.

Back 112

Sinuatrial node depolarization; Heart rate

Front 113

Nodal areas have high _____ _____ activity so the transmitter is cleared rapidly.

Back 113

ACh esterase

Front 114

Sympathetic fibers originate from _____ _____ ganglia and primarily innervate the _____ _____.

Back 114

Sympathetic chain; Sinoatrial node

Front 115

_____ is the transmitter which increases heart rate.

Back 115

Norepinephrine

Front 116

Elevated _____ and _____ can act directly on the SA node to increase the heart rate.

Back 116

Temperature; Stretch

Front 117

Sympathetics also innervate the _____ _____ where norepinephrine increases _____ _____.

Back 117

Atrioventricular node; Conduction velocity

Front 118

The sinus (sinuatrial) node is a specialized _____ located in the _____ _____ wall of the _____ atrium just _____ and _____ to opening of _____ vena cava.

Back 118

Muscle; Superior Posterior Lateral; Right; Below; Lateral; Superior

Front 119

The sinus (sinuatrial) node contains almost no _____ filaments, however nodal fibers connect directly with _____ muscle fibers.

Back 119

Contractile; Atrial

Front 120

_____ _____ that begin in the sinus (sinuatrial) node spread immediately into the _____ muscle wall.

Back 120

Action potentials; Atrial

Front 121

The conducting system has the capability of _____-_____ that results in automatic _____ _____ and _____.

Back 121

Self-excitation; Rhythmical discharge; Contraction

Front 122

The sinus (sinoatrial) node has the capability of _____-_____ and it will _____ the rate of the heart beat.

Back 122

Self-excitation; Control

Front 123

Resting membrane potential of _____ fibers is _____ negative (-55 to -60 mv) in comparison to _____ muscle (-85 to -90 mv)

Back 123

Nodal; Less; Ventricle

Front 124

Cell membranes of nodal fibers are leaky to _____ and _____ ions that _____ intracellular negativity.

Back 124

Na+; Ca++; Neutralize

Front 125

Differences in the functioning of _____ _____ in the nodal fibers are due to less negative resting potential.

Back 125

Ion channels

Front 126

Fast _____ channels cause upstroke of action potential from ~-90 mv as _____ enters the cell.

Back 126

Na+;Na+

Front 127

Slow _____-_____ channels create the plateau of the action potential.

Back 127

Na+; Ca++

Front 128

Opening of _____ channels allowing outflow of _____ ions returns membrane potential to resting levels.

Back 128

K+; K+

Front 129

Action potentials begin at a less negative _____ _____ (-55 mv, and some _____ channels are blocked or inactivated.

Back 129

Resting potential; Na+

Front 130

High _____ ion concentration outside of _____ fibers with open channels results in _____ ions leaking into fiber and a slow rise in the _____ potential in a _____ direction.

Back 130

Na+; Nodal; Na+; Resting; Positive

Front 131

At the threshold voltage of ___ mv, slow Na+ - Ca++ channels _____ causing the _____ potential, which is _____ to develop than the _____ potential in the muscle fiber.

Back 131

-40 mv; Open; Action; Slower; Action

Front 132

What does the inherent leakiness of the sinus nodal fibers to Na+ and Ca++ ions cause?

Back 132

Self-excitation of the sinus nodal fibers

Front 133

Return to the _____ state occurs more _____ in sinus nodal fiber when compared to the ventricular muscle fiber.

Back 133

Resting; Slowly

Front 134

_____ channels remain _____ a few tenths of a second resulting in excess negativity (_____) of the nodal fiber to -55 to -60 mv at the termination of the _____ potential when the _____ channels _____.

Back 134

K+; Open; Hyperpolarization; Action; K+; Close

Front 135

The action potential generated in the sinus node spreads outward in specialized _____ of _____ fibers.

Back 135

Bands; Atrial

Front 136

What band goes through the anterior wall of the atrium into the left atrium?

Back 136

Anterior interatrial band

Front 137

What internodal pathways traverse the atria and terminate in the AV node?

Back 137

Anterior, Middle, Posterior

Front 138

The anterior, middle, and posterior internodal pathways traverse the _____ and terminate in the _____ node.

Back 138

Atria; Atrioventricular (AV)

Front 139

The internodal pathways have an inherent conduction delay (0.03 sec) of the cardiac impulse that allows time for the _____ to _____ blood into the _____ before _____ contraction begins.

Back 139

Atria; Empty; Ventricles; Ventricular

Front 140

The atrioventricular node and its adjacent conductive fibers delay the _____ impulse transmission into the _____.

Back 140

Cardiac; Ventricles

Front 141

What two structures delay the cardiac impulse transmission into the ventricles?

Back 141

Atrioventricular (AV) node, Adjacent conductive fibers

Front 142

Where is the atrioventricular (AV) node located?

Back 142

Posterior wall of the right atrium

Front 143

What do the fibers of the atrioventricular (AV) bundle penetrate?

Back 143

Fibrous tissue between atria and ventricles

Front 144

The _____ portion of the atrioventricular (AV) bundle divides into the _____ and _____ _____ branches.

Back 144

Distal; Left; Right bundle

Front 145

How long is the total delay in the atrioventricular (AV) nodal and bundle system?

Back 145

0.13 sec

Front 146

There is a one-way _____ through the atrioventricular (AV) bundle that prevents the _____ from traveling backward from ventricles to atria.

Back 146

Conduction; Impulse

Front 147

A _____ barrier exists between the _____ tissue of the atria and the ventricles such that the atrioventricular (AV) node and bundle system is the only means of _____ _____ between atria and ventricles.

Back 147

Fibrous; Muscle; Impulse conduction

Front 148

Purkinje fibers lead from the _____ _____ through the _____ _____ into the _____.

Back 148

Atrioventricular (AV) node; AV bundle; Ventricles

Front 149

Purkinje fibers are _____ diameter fibers.

Back 149

Large

Front 150

Purkinje fibers have _____ permeability at the _____ junctions.

Back 150

High; Gap

Front 151

After Purkinje fibers penetrate the _____ barrier, they transmit the action potential ___x faster than the _____ muscle.

Back 151

Fibrous; 6; Ventricular

Front 152

Purkinje fibers transmit the action potential _____ through the ventricles.

Back 152

"Instantaneously"

Front 153

Purkinje fibers penetrate ___ of the way into the ventricle wall and become continuous with _____ _____.

Back 153

1/3; Muscle fibers

Front 154

The sinus node controls heart beat because its _____of _____ is faster than that of other parts of the heart.

Back 154

Rate of discharge

Front 155

List the range of rates of discharge:
Sinus node
AV node
Purkinje fibers

Back 155

70 - 80 / min
40 - 60 / min
15 - 40 / min

Front 156

A pacemaker elsewhere than the sinus node is called an _____ pacemaker.

Back 156

Ectopic

Front 157

An ectopic pacemaker causes abnormal _____ of _____ and affects heart _____.

Back 157

Sequence of contraction; Pumping

Front 158

What is the condition where impulse from the sinus node to the heart is blocked and the AV node or bundle becomes the pacemaker?

Back 158

Sinoatrial Block

Front 159

What is the condition where impulse from the atria to ventricles is blocked?

Back 159

Atrioventricular (AV) block

Front 160

during an AV block, the atria beat normally with _____ _____ impulse and the _____ _____ in the ventricles becomes the pacemaker

Back 160

Sinus node; Purkinje system

Front 161

What is the syndrome which follows a sudden AV block where impulses are not conducted and a delay of about 5 - 20 seconds occurs before the ventricles contract?

Back 161

Stokes-Adams syndrome

Front 162

What may result from Stokes-Adams syndrome?

Back 162

Fainting; Death

Front 163

In Stokes-Adams syndrome, what part of the heart becomes the pacemaker?

Back 163

Purkinje system--usually distal AV node or bundle

Front 164

Parasympathetics (from ______) are distributed mainly to the _____ and _____ _____, and to a lesser extent, the muscle of the _____ and, lesser still, the _____ muscle.

Back 164

Vagus (CN X); Sinus; AV nodes; Atria; Ventricular

Front 165

Sympathetics (from _____ _____ _____) are distributed to _____ parts of the heart, with strong innervations to _____ and other areas.

Back 165

Sympathetic chain ganglia; All; Ventricles

Front 166

Vagal stimulation releases _____ into the heart.

Back 166

Acetylcholine

Front 167

Acetylcholine _____ rate and rhythm of the _____ node and _____ the excitability of the _____ junctional fibers between _____ musculature and the _____ node. _____ transmission of the cardiac impulse into the _____.

Back 167

Decreases; Sinus; Decreases; Atrioventricular (AV); Atrial; AV; Slowing; Ventricles

Front 168

Weak to moderate _____ stimulation slows the rate of heart pumping.

Back 168

Vagal

Front 169

Strong vagal stimulation can block signal transmission from _____ to _____ _____.

Back 169

Sinus; Atrioventricular (AV) nodes

Front 170

Strong vagal stimulation may cause the ventricles to stop beating for 5 - 20 seconds after which part of the Purkinje stem (AV bundle) establishes a rhythm of ventricular contraction ~ 15 - 40 bpm. What is this called?

Back 170

Ventricular escape

Front 171

Sympathetic stimulation releases _____ and _____ overall activity of the heart.

Back 171

Norepinephrine; Increases

Front 172

Sympathetic stimulation:
Increases rate of _____ _____ discharge.
Increases rate of _____ and _____ in all of the heart.
Increases _____ of _____ in all cardiac muscle

Back 172

Sinus node; Conduction; Excitability; Force of contraction

Front 173

The increased force of contraction from sympathetic stimulation may be due to increased _____ of fibers to _____ and _____ ions.

Back 173

Permeability; Na+; Ca++

Front 174

The electrocardiogram (ECG) is composed of _____, _____ and _____.

Back 174

Waves; Segments; Intervals

Front 175

What are the three major waves on a lead I electrocardiogram?

Back 175

P wave, QRS complex, T wave

Front 176

P wave signifies _____ _____.

Back 176

Atrial depolarization

Front 177

QRS complex signifies _____ _____.

Back 177

Ventricle depolarization

Front 178

T wave signifies _____ of _____.

Back 178

Repolarization of ventricles

Front 179

P wave immediately precedes _____ contraction.

Back 179

Atrial

Front 180

QRS complex immediately precedes _____ contraction.

Back 180

Ventricular

Front 181

Ventricles remain _____ until a few msec after the end of the T _____ wave.

Back 181

Contracted; Repolarization

Front 182

Atria remain contracted until they _____; but this wave is obscured by the _____ wave.

Back 182

Repolarize; QRS

Front 183

What is the time between the beginning of the P wave and the beginning of the QRS complex?

Back 183

P-Q or P-R interval

Front 184

The P-Q or P-R interval represents the time between the beginning of _____ of the atria and of the ventricles.

Back 184

Excitation

Front 185

The Q-T interval represents the time from the _____ of the Q wave to the _____ of the T wave.

Back 185

Beginning; End

Front 186

The Q-T interval approximates the time of _____ contraction.

Back 186

Ventricular

Front 187

What are the sections of baseline between two waves called?

Back 187

Segments

Front 188

What are the segments on the lead 1 tracing of the ECG?

Back 188

P-R Segment, S-T Segment

Front 189

An ECG (is/is not) the same as a single action potential.

Back 189

Is not

Front 190

The action potential is _____ electrical event in a _____ cell.

Back 190

One; Single

Front 191

ECG is a(n) _____ recording that represents the sum of multiple _____ _____ taking place in many cardiac cells.

Back 191

Extracellular; Action potentials

Front 192

An ECG is an electrical "view" of a _____ object.

Back 192

3-dimensional

Front 193

ECG provides info on _____ _____, _____, _____ _____, and _____ of _____ in the heart.

Back 193

Heart rate; Rhythm; Conduction velocity; Condition; Tissues

Front 194

during depolarization the normal _____ potential inside the cardiac muscle fiber reverses and becomes slightly _____ inside and _____ outside.

Back 194

Negative; Positive; Negative

Front 195

In an ECG, complete _____ has both electrodes reading a negative potential.

Back 195

Depolarization

Front 196

In an ECG, _____ has positivity returning to the outside of the fiber.

Back 196

Repolarization

Front 197

In an ECG, complete _____ has both electrodes reading a positive potential.

Back 197

Repolarization

Front 198

What is the heart rate?

Back 198

Time between two successive heart beats

Front 199

Heart rate is normally timed from the beginning of one ___ peak to the next (the ___-___ interval).

Back 199

R; R-R

Front 200

If the timed R-R interval is 1.0 second, the heart rate is ___ bpm.

Back 200

60

Front 201

Commonly, the heart interval is ___ sec, resulting in a heart rate of ___ bpm.

Back 201

0.83; 72

Front 202

What type of circulation serves all tissues except lungs?

Back 202

Systemic (Peripheral)

Front 203

What type of circulation serves the lungs?

Back 203

Pulmonary

Front 204

Systemic (Peripheral) Circulation contains ___% of blood volume (___% in veins, ___% in arteries, ___% in arterioles and capillaries).

Back 204

84; 64; 13; 7

Front 205

Pulmonary circulation contains ___% of blood volume (heart contains ___%, vessels contain ___%)

Back 205

16; 7; 9

Front 206

What types of vessels have the largest area and function in storage?

Back 206

Veins

Front 207

Velocity of blood flow is _____ proportional to cross-sectional area.

Back 207

Inversely

Front 208

Blood pressure is highest in _____ and decreases continuously as blood flows through the system.

Back 208

Arteries

Front 209

Blood pressure decreases as energy is lost as a result of _____ to flow by vessels and friction between blood _____.

Back 209

Resistance; Cells

Front 210

Highest blood pressure is in the _____ of ___ mm Hg during ventricular _____ (_____ pressure)

Back 210

Aorta; 120; Systole; Systolic

Front 211

Blood pressure falls to a low of ___ mm Hg during ventricular _____ (_____ pressure)

Back 211

80; Diastole; Diastolic pressure

Front 212

What type of blood pressure reflects driving pressure created by the pumping of the heart.

Back 212

Arterial

Front 213

What type of blood pressure reflects ventricular pressure?

Back 213

Assumed

Front 214

What is used to represent the driving pressure for blood flow?

Back 214

Mean Arterial Pressure (MAP)

= diastolic P - 1/3 (systolic P - diastolic P)

Front 215

For a person at rest whose systolic pressure is 120 and diastolic pressure is 80, what is the mean arterial pressure?

Back 215

MAP = 80 + 1/3 (120 - 80)
MAP = 93 mm Hg

Front 216

Mean arterial pressure is closer to _____ pressure because _____ lasts twice as long as _____ at rest (60 - 80 bpm).

Back 216

Diastolic; Diastole; Systole

Front 217

Arterial pressure is a _____ of flow _____ and _____ of the arteries.

Back 217

Balance; In; Out

Front 218

Blood flow into the aorta is equal to the _____ _____.

Back 218

Cardiac output (CO)

Front 219

Blood flow out of arteries is _____ by _____ _____ (flow at arteriolar level).

Back 219

Influenced; Peripheral resistance

(MAP is proportional to CO x R of arterioles)

Front 220

If _____ _____ increases, more blood is pumped into arteries.

Back 220

Cardiac output

Front 221

If cardiac output increases and _____ does not change, blood volume in arteries _____ and so does arterial pressure.

Back 221

Resistance; Increases

Front 222

If cardiac output is _____ but resistance _____. flow in is the same but flow out is less, so arterial blood volume and pressure _____.

Back 222

Unchanged; Increases; Increases

Front 223

The rate of blood flow to tissues is controlled in relation to _____ _____.

Back 223

Tissue needs

Front 224

Active tissues need increased supply of _____.

Back 224

Nutrients

Front 225

Increase _____ _____ has its limits, therefore increasing blood flow to the entire body is not possible when some tissues are _____.

Back 225

Cardiac output; Active

Front 226

Microvasculature monitors tissue needs and _____ or _____ as needed.

Back 226

Constricts; Dilates

Front 227

Cardiac output is mainly controlled by _____ _____ flow.

Back 227

Local tissue

Front 228

The heart responds automatically to blood returning to it through the _____ _____ and pumps it through the system.

Back 228

Vena cava

Front 229

The heart responds to the _____ of the tissues.

Back 229

Demands

Front 230

The ANS assists in _____ heart pumping and blood flow.

Back 230

Controlling

Front 231

The ANS can _____ arterial pressure _____ from either local blood control or cardiac output.

Back 231

Control; Independently

Front 232

Should pressure _____ significantly below 100 mm Hg, the ANS _____:
_____ the force of heart pumping.
_____ large venous reservoirs to get more blood to the heart.
_____ _____ most arterioles to allow blood to accumulate in arteries to increase arterial pressure.

Back 232

Fall; Responds; Increasing; Contracting; Generally constricting

Front 233

What describes the physical behavior of blood as a fluid?

Back 233

Hemodynamics

Front 234

Hemodynamics examines the _____ between flow, pressure gradients, resistance, vessel cross-sectional area, and velocity.

Back 234

Interrelationships

Front 235

Hemodynamic relationships _____ arterial pressure, cardiac output, and tissue blood flow (and explain the appearance of murmurs and bruits).

Back 235

Determine

Front 236

In Hemodynamics, what does F or Q represent?

Back 236

Flow: Volume of blood moved with respect to time

Front 237

In Hemodynamics, what does P represent?

Back 237

Pressure: Force exerted by blood over a surface

(e.g., unit area of vessel wall)

Front 238

In Hemodynamics, what does ΔP represent?

Back 238

Pressure difference between two ends of the vessel

(P1 at origin, P2 at end)

Front 239

In Hemodynamics, what does R represent?

Back 239

Resistance: Impediment to flow in a vessel, expressed in resistance units

Front 240

What does Ohm's law calculate?

Back 240

Blood flow through a vessel

Front 241

What is Ohm's law?

Back 241

F = ΔP/R

Front 242

Flow is proportional to ___ and inversely proportional to ___.

Back 242

ΔP; R

Front 243

According to Ohm's law, what is the primary factor that alters the rate of flow?

Back 243

Vascular resistance

Front 244

What is blood flow? How is it expressed?

Back 244

The amount of blood moved in a given time; ml / min or L / min

Front 245

In adults the overall flow in the circulatory system is ___/___ which is the _____ _____.

Back 245

5 L / min; Cardiac output (CO)

Front 246

Blood flows in _____, or concentric circles, and is fastest at the _____. This flow is called _____ flow.

Back 246

Streamlines; Center; Laminar

Front 247

Laminar flow is _____, and due to the increasing speed of flow towards the _____ of the vessel, a ‘_____ profile for velocity of blood’ is created.

Back 247

Silent; Center; Parabolic

Front 248

Causes of turbulent blood flow :
_____ velocities
_____ _____ in the circulation
Passes over _____ _____ in vessels
Passes by an _____ or _____ _____

Back 248

High; Sharp turns; Rough surfaces; Obstruction; Rapid narrowing

Front 249

_____ currents or _____ are created resulting in greater resistance and friction in flow.

Back 249

Eddy; Whorls

Front 250

What 2 problems may turbulent blood flow result in?

Back 250

Murmurs, Bruits

Front 251

What are 2 disorders caused by the negative effects of wall stress on vessels?

Back 251

Aortic aneurysm; Atherosclerosis

Front 252

Resistance is the _____ to flow and is measured indirectly by dividing the _____ _____ _____ by the ____ _____.

Back 252

Impediment; Vessel pressure difference (P1 – P2); Blood flow

Front 253

The higher the _____, the lower the blood flow.

Back 253

Resistance

Front 254

Blood flow will take the path of _____ _____.

Back 254

Least resistance

Front 255

In identical vessels, flow in _____ flow out.

Back 255

Equals

Front 256

With constriction, resistance _____ and flow _____. Diverted blood is divided among _____ resistance vessels.

Back 256

Increases; Decreases; Lower

Front 257

What is conductance?

Back 257

Measure of blood flow through a vessel for a given pressure difference.

Front 258

What is a measure of blood flow through a vessel for a given pressure difference termed?

Back 258

Conductance

Front 259

Conductance is the _____ of resistance.

Back 259

Reciprocal

(C = 1 / R)

Front 260

Changes in vessel _____ cause tremendous changes in the vessel’s ability to conduct blood.

Back 260

Diameter

Front 261

Conductance of a vessel increases in proportion to the _____ power of the diameter

Back 261

Fourth

Front 262

The relationship between vessel radius, vessel length and viscosity of the blood is described by _____ Law.

Back 262

Poiseuille’s

(F = πΔPr^4 / 8ηl)

Front 263

The relationship between vessel _____, vessel _____ and _____ of the blood is described by Poiseuille’s Law.

Back 263

Radius (r), Length (l), Viscosity (η)

Front 264

_____ to _____ by the vessel increases with length of the vessel

Back 264

Resistance to flow

Front 265

Resistance increases as viscosity of fluid _____.

Back 265

Increases

Front 266

Resistance decreases as radius _____.

Back 266

Increases

Front 267

_____ _____ _____ contribute to blood viscosity as they exert frictional drag against the vessel wall.

Back 267

Red blood cells

Front 268

What is the hematocrit?

Back 268

Cellular component of blood

Front 269

Hematocrit of 40 means 40% of blood volume are _____, the rest is _____

Back 269

Cells; Plasma

Front 270

Average hematocrit values:
men = ___, women = ___

Back 270

42; 38

Front 271

what is an abnormally low hematocrit termed?

Back 271

Anemia

Front 272

what is an abnormally high hematocrit termed?

Back 272

Polycythemia

Front 273

What are bruits?

Back 273

Abnormal blowing or swishing sounds

Front 274

Hematocrit is _____ to viscosity.

Back 274

Proportional

Front 275

All blood vessels are _____; as pressures increases the vessel stretches (dilates).

Back 275

Distensible

Front 276

What type of blood vessels are distensible?

Back 276

All types

Front 277

Anatomically, _____ walls are stronger than _____.

Back 277

Arterial; Veins

Front 278

Veins are ___x more distensible than arteries.

Back 278

8

Front 279

What is defined as the total quantity of blood that can be stored in a given portion of the circulation for each mm Hg.

Back 279

Vascular Compliance or Capacitance

Front 280

What is a more meaningful parameter to measure than distensibility?

Back 280

Vascular Compliance or Capacitance

Front 281

Vascular Compliance or Capacitance is defined as the total _____ of blood that can be _____ in a given portion of the circulation for each ___ ___.

Back 281

Quantity; Stored; mm Hg

Front 282

Vascular _____ = Increase in volume / Increase in pressure

Back 282

Vascular Compliance or Capacitance

Front 283

Why may a highly distensible vessel not have high compliance?

Back 283

The blood volume in the vessel must be accounted for

Front 284

_____ = Distensibility x Volume

Back 284

Vascular Compliance or Capacitance

Front 285

_____ of a systemic vein is 24x that of arteries; it is 8x as _____ and has 3x the _____ (24 = 8 x 3).

Back 285

Compliance; Distensible; Volume

Front 286

_____-_____ relationships reflect compliance of the vascular system .

Back 286

Volume-Pressure

Front 287

Arteries have _____ compliance so _____ _____ changes cause large pressure changes.

Back 287

Low; Small volume

Front 288

Veins have _____ compliance, so _____ _____ changes cause only small changes in pressure.

Back 288

High; Large volume

Front 289

When veins _____, more blood flows to the heart increasing _____ _____.

Back 289

Constrict; Cardiac output (CO)

Front 290

With each beat, _____ waves are sent through the arterial tree.

Back 290

Pressure

Front 291

What almost equals [CO x R (of arterioles)]?

Back 291

Mean arterial pressure (MAP)

Front 292

What is the measure of the strength of the pressure wave?

Back 292

Pulse pressure

Front 293

What is defined as (systolic pressure – diastolic pressure)?

Back 293

Pulse pressure

Front 294

For an average person:
120 mmHg – 80 mm Hg = 40 mmHg (_____ _____ at aorta)

Back 294

Pulse pressure

Front 295

Increases in _____ _____ increase pulse pressure; conversely decreases in _____ _____ decrease pulse pressure.

Back 295

Stroke volume; Stroke volume

Front 296

Increases in stroke volume _____ pulse pressure; conversely decreases in stroke volume _____ pulse pressure

Back 296

Increase; Decrease

Front 297

Decreases in _____ _____ will increase pulse pressure; conversely increases in _____ _____ decrease pulse pressure.

Back 297

Arterial compliance (or capacitance); Arterial compliance (or capacitance)

Front 298

Decreases in compliance will _____ pulse pressure; conversely increases in compliance _____ pulse pressure

Back 298

Increase; Decrease

Front 299

What is the term that describes the effect where intensity of pulsations becomes progressively less in smaller arteries?

Back 299

Damping

Front 300

Damping describes how the intensity of pulsations becomes progressively _____ in _____ arteries

Back 300

Less; Smaller

Front 301

The degree of damping is proportional to the _____ and _____ of the vessels.

Back 301

Resistance; Compliance

Front 302

How do clinicians measure systolic and diastolic pressures indirectly?

Back 302

Via the auscultatory method

Front 303

Cuff inflation beyond ___ mm Hg occludes the brachial artery.

Back 303

120

Front 304

As cuff pressure is released, turbulence is generated when blood from the _____ side of the cuff meets the _____ blood .

Back 304

Heart; Downstream

Front 305

As cuff pressure is released, an audible event called _____ _____ occurs due to the turbulence of blood flow.

Back 305

Korotkoff sounds

Front 306

In general, blood pressure _____ with age.

Back 306

Increases

Front 307

What percentage of blood is in veins?

Back 307

64%

Front 308

What can constrict and enlarge thereby storing small or large volumes of blood available when required by the circulation?

Back 308

Veins

(Reservoir function)

Front 309

Veins can constrict and enlarge thereby _____ small or large _____ of blood available when required by the circulation.

Back 309

Storing; Volumes

Front 310

Peripheral veins use the _____ ______ (_____ muscle contraction) mechanism to propel blood to heart and assist in _____ CO.

Back 310

Venous pump; Skeletal; Regulating

Front 311

_____, _____, _____ _____ veins and the venous _____ also serve as reservoirs.

Back 311

Spleen; Liver; Large abdominal; Plexus

Front 312

_____ flow goes into right atrium, so pressure in the right atrium is called the _____ _____ pressure.

Back 312

Venous; Central venous

Front 313

_____ _____ _____ is regulated by the balance between:
1. Ability of heart to pump blood out of the right atrium and ventricle into the lungs
2. Blood flows from the peripheral veins into the right atrium

Back 313

Right atrial pressure (RAP)

Front 314

If the right side of the heart is pumping strongly, Right atrial pressure (RAP) _____.

Back 314

Decreases

Front 315

Factors that elevate Right atrial pressure (RAP):
_____ heart function
Any effect causing rapid inflow of blood into _____
_____ blood volume
_____ systemic vessel tone resulting in _____ peripheral venous pressures
_____ of arterioles

Back 315

Decreased; Atrium; Increased; Increased; Increased; Dilation

Front 316

Compression factors result in _____ to flow in peripheral veins.

Back 316

Impedance

Front 317

Increased _____ _____ _____ causes blood to backup in the venous system; increasing venous pressure.

Back 317

Right atrial pressure (RAP)

Front 318

Increased Right atrial pressure (RAP) causes blood to backup in the _____ _____; increasing _____ pressure.

Back 318

Venous system; Venous

Front 319

Abdominal pressure increases _____ pressure in the legs.

Back 319

Venous

Front 320

To assist venous flow, some veins have internal _____ _____ that ensure blood passing the valve cannot flow backward.

Back 320

One-way valves

(e.g., lower extremity)

Front 321

_____ _____ to the heart is aided by the venous pump and respiratory pump.

Back 321

Venous return

Front 322

_____ _____ contraction squeezes veins (e.g., in legs), compressing them and pushing blood toward heart.

Back 322

Skeletal muscle

Front 323

During periods of sitting or standing motionless, the venous _____ does not assist venous _____.

Back 323

Pump; Return

Front 324

_____ incompetence results in varicose veins.

Back 324

Valve

Front 325

What is a sphygmomanometer?

Back 325

Device used to measure blood pressure

Front 326

What is a normal measurement of right arterial pressure (RAP)?

Back 326

Approximately 0 mm Hg

Front 327

Valve incompetence results in varicose veins, which predisposes one to _____.

Back 327

Edema

Front 328

What are the five types of structures in the microcirculation?

Back 328

Nutrient arteries, Arterioles, Metarterioles, Capillaries; Venules

Front 329

In microcirculation, the nutrient artery enters _____ or _____.

Back 329

Organ; Tissue

Front 330

In microcirculation, the arterioles are highly _____.

Back 330

Muscular

Front 331

In microcirculation, metarterioles are _____ arterioles with _____ _____ fibers encircling the tube _____.

Back 331

Terminal; Smooth muscle; Intermittently

Front 332

In microcirculation, capillaries originate from _____ and their entrances are encircled by the _____ _____.

Back 332

Metarterioles; Precapillary sphincter

Front 333

In microcirculation, venules are _____ than arterioles and the muscle in the walls is _____ than muscle in the walls of arterioles, yet they can still _____ considerably

Back 333

Larger; Weaker; Contract

Front 334

What have the thinnest walls of all blood vessels?

Back 334

Capillaries

Front 335

Capillaries are divided into what two categories?

Back 335

Continuous, Fenestrated

Front 336

_____ capillaries are found in muscle, connective tissues and neural tissue.

Back 336

Continuous

Front 337

_____ capillaries are found in kidney and intestine.

Back 337

Fenestrated

Front 338

What type of capillary has large pores in it that allow high volumes of fluid to pass between the plasma and interstitial fluid.

Back 338

Fenestrated

Front 339

Fenestrated capillaries have large _____ in them that allow high volumes of fluid to pass between the _____ and _____ _____.

Back 339

Pores; Plasma; Interstitial fluid

Front 340

Continuous capillaries have _____ _____; thin, curving channels between cells.

Back 340

Intercellular clefts

Front 341

Intercellular clefts in _____ capillaries allow water, dissolved _____ and small _____ to pass through the wall.

Back 341

Continuous; Solutes; Ions

Front 342

_____ capillaries have pores that allow _____ through the cell

Back 342

Fenestrated; Transcytosis

Front 343

In _____ capillaries, transcytosis _____ can form _____ channels

Back 343

Fenestrated; Vesicles; Vesicular

Front 344

Blood flows _____ through capillaries.

Back 344

Intermittently

Front 345

What is the term that describes the intermittent contraction of metarterioles and precapillary sphincters.

Back 345

Vasomotion

Front 346

The term vasomotion describes the intermittent _____ of _____ and _____ _____.

Back 346

Contraction; Metarterioles; Precapillary sphincters

Front 347

_____ _____ is the primary regulator of vasomotion.

Back 347

Oxygen concentration

Front 348

Increase in the _____ of _____ usage in tissue causes periods of capillary blood flow to occur more _____.

Back 348

Rate; Oxygen; Often

Front 349

Increase in the _____ of _____ usage in tissue causes the duration of each period of capillary blood flow to be _____.

Back 349

Rate; Oxygen; Longer

Front 350

In _____, dissolved solutes and gases move by _____, determined by concentration _____ between _____ and _____ fluid.

Back 350

Capillaries; Diffusion; Gradients; Plasma; Interstitial

(exchange)

Front 351

Lipid _____ substances diffuse directly through the cell membrane of the _____.

Back 351

Soluble; Capillary

(e.g., O2, CO2)

Front 352

Lipid _____ substances cross the cell membrane via intercellular _____.

Back 352

Insoluable; Clefts

(e.g., H2O, Na, Cl, glucose)

Front 353

the space between cells is the _____; substance in this space is the _____ _____.

Back 353

Interstitium; Interstitial fluid

Front 354

_____ _____ and _____ _____ are two major solid structures in the interstitium.

Back 354

Collagen fibers; Proteoglycan filaments

Front 355

Almost all interstitial fluid is in form of a _____.

Back 355

Gel

Front 356

Bulk flow refers to mass movement of fluid between _____ and _____ _____ as the result of _____ or _____ pressure gradients.

Back 356

Blood; Interstitial fluid; Hydrostatic; Osmotic

Front 357

If the direction of bulk flow is into the capillary, the fluid movement is called _____.

Back 357

Absorption

Front 358

If the direction of flow is out of the capillary, the fluid movement is called _____.

Back 358

Filtration

Front 359

Capillary filtration is caused by _____ pressure that forces fluid _____ _____ the capillary through _____ cell _____.

Back 359

Hydrostatic; Out of; Leaky; Junctions

Front 360

Most capillaries show a transition from net _____ at the arterial end to net _____ at the venous end.

Back 360

Filtration; Absorption

Front 361

Most capillaries show a transition from net filtration at the _____ end to net absorption at the _____ end.

Back 361

Arterial; Venous

Front 362

Exceptions to the rule of capillary filtration and absorption are found in the _____ (_____ entire length) and _____ (only _____).

Back 362

Kidney; Filters; Intestine; Absorbs

Front 363

What is the lateral pressure component of blood flow that pushes fluid out through the capillary pores?

Back 363

Hydrostatic pressure

Front 364

What is determined by the solute concentration differences between two compartments?

Back 364

Osmotic pressure

Front 365

The main difference in solutes between plasma and interstitial fluid are the _____ present in _____.

Back 365

Proteins; Plasma

Front 366

Hydrostatic Pressure is the _____ pressure component of blood flow that pushes fluid _____ through the capillary _____.

Back 366

Lateral; Out; Pores

Front 367

Osmotic Pressure is determined by the _____ _____ differences between two compartments.

Back 367

Solute concentration

Front 368

What is the osmotic pressure due to the presence of proteins in plasma known as?

Back 368

Colloid osmotic pressure

Front 369

Colloid osmotic pressure exists because of the presence of _____ in _____.

Back 369

Proteins; Plasma

Front 370

Colloid osmotic pressure is NOT the same as _____ osmotic pressure; it is a measure of the osmotic pressure created by _____.

Back 370

Total; Proteins

Front 371

Because of _____ osmotic pressure, the osmotic gradient favors H2O movement by osmosis from _____ _____ into _____.

Back 371

Colloid; Interstitial fluid; Plasma

Front 372

_____ _____ pressure decreases along the length of the capillary as energy is lost due to _____.

Back 372

Capillary hydrostatic; Friction

Front 373

The average value of capillary hydrostatic pressure at the _____ end is 32 mm Hg and 15 mm Hg at the _____ end.

Back 373

Arterial; Venous

Front 374

Water movement will always be directed _____ _____ the capillary, with pressure _____ from the arterial end to the venous end.

Back 374

Out of; Decreasing

Front 375

_____ fluid flow across the capillary is determined by the difference between the _____ _____ _____ _____ (Pcap) favoring filtration and the _____ _____ _____ (π) favoring absorption.

Back 375

Net; Capillary hydrostatic pressure gradient; Colloid osmotic pressure

Front 376

Continuous capillaries have _____ junctions.

Back 376

Tight

Front 377

_____ (Pout) = hydrostatic pressure gradient = (Pcap – PIF)

Back 377

Filtration

Front 378

_____ (πin) = colloid osmotic pressure gradient = (πIF – πcap)

Back 378

Absorption

Front 379

Net pressure = _____ ______ gradient + _____ _____ _____ gradient.

Back 379

Hydrostatic pressure; Colloid osmotic pressure

Front 380

Net pressure at the _____ end of the capillary is 7 mm Hg.

Back 380

Arterial

Front 381

The hydrostatic pressure gradient (Pcap) is greater than the colloid osmotic pressure gradient (π) at the _____ end of a capillary, favoring _____.

Back 381

Arterial; Filtration

Front 382

Filtration is usually _____ than absorption, resulting in bulk flow of fluid out of the _____ into _____ _____.

Back 382

Greater; Capillary; Interstitial space.

Front 383

Unless fluid is returned to the _____, the blood will become a sludge of _____ and _____.

Back 383

Plasma; Cells; Proteins

Front 384

Restoring lost fluid from capillaries to circulation is one of the functions of the _____ _____.

Back 384

Lymphatic system

Front 385

Vessels of the lymphatic system interact with the _____ system, the _____ system and the _____ system.

Back 385

Cardiovascular; Digestive; Immune

Front 386

Functions of the lymph system:
Return _____ and _____ to the circulation
Pick up _____ from _____ intestine and transfer it to the circulatory system
Filter, capture and destroy _____ _____

Back 386

Fluid; Proteins; Fat; Small; Foreign pathogens

Front 387

The _____ system is designed for _____ movement of interstitial fluid from the tissues to the circulation.

Back 387

Lymph; One-way

Front 388

_____ _____ lie close to all blood capillaries except in the kidney and CNS.

Back 388

Lymph capillaries

Front 389

Large gaps in lymph capillaries allow _____, _____and _____ matter to come into the capillary via bulk flow.

Back 389

Fluid; Proteins; Particulate

Front 390

Fluid, proteins, and particulate matter make up the _____.

Back 390

Lymph

Front 391

Lymph capillaries connect to larger vessels, and eventually empty into the _____ circulation just under the _____ where the _____ _____ veins join the _____ _____ veins.

Back 391

Venous; Clavicles; Right subclavian; Internal jugular

Front 392

At intervals along the way, vessels enter lymph _____ that contain immunologically active cells such as _____ and _____.

Back 392

Nodes; Lymphocytes; Macrophages

Front 393

If _____ move from plasma to interstitial fluid, the _____ _____ _____ opposing filtration decreases.

Back 393

Proteins; Osmotic pressure gradient

Front 394

With less opposition to _____ _____ _____, fluid moves into the interstitial space.

Back 394

Capillary hydrostatic pressure

Front 395

Local swelling in response to inflammation is an example of _____ caused by redistribution of _____ from plasma to interstitial fluid.

Back 395

Edema; Proteins

Front 396

What is a sign that normal capillary-lymph exchange is disrupted?

Back 396

Edema

Front 397

Edema arises from one of two causes:
1. Inadequate drainage of _____.
2. Capillary filtration that _____ _____ capillary absorption.

Back 397

Lymph; Greatly exceeds

Front 398

What occurs with obstruction of the lymph system, particularly at lymph nodes?

Back 398

Inadequate drainage of lymph

Front 399

Causes of inadequate drainage of lymph:
1. _____
2. _____
3. _____ tissue growth following radiation therapy
4. Surgical removal of _____

Back 399

Parasites; Cancer; Fibrotic; Nodes

Front 400

Factors disrupting balance between capillary filtration and absorption:
1. Increase in _____ _____ _____
2. Decrease in _____ _____ _____
3. Increase in interstitial _____

Back 400

Capillary hydrostatic pressure; Plasma protein concentration; Proteins

Front 401

Plasma protein concentrations may decrease as a result of severe _____ or _____ failure.

Back 401

Malnutrition; Liver

Front 402

The _____ is the main site for plasma protein synthesis.

Back 402

Liver

Front 403

Excessive leakage of _____ _____ ____ blood will decrease plasma colloid osmotic pressure and increase net capillary filtration.

Back 403

Proteins; Out of

Front 404

On occasion, changes between filtration and absorption _____ homeostasis.

Back 404

Help

Front 405

If arterial blood pressure falls due to hemorrhage or severe dehydration, _____ _____ _____ also falls. This change _____ fluid absorption.

Back 405

Capillary hydrostatic pressure; Increases

Front 406

If pressure falls low enough, net _____ in capillaries occurs rather than net _____, maintaining blood volume.

Back 406

Absorption; Filtration

Front 407

Each tissue controls its own blood flow in proportion to its _____.

Back 407

Needs

Front 408

Each _____ controls its own blood flow in proportion to its needs.

Back 408

Tissue

Front 409

Tissue needs:
Delivery of ___
Delivery of nutrients; _____, _____, and _____ _____.
Removal of ___, ___ and other metabolites
Transport of various _____ and other substances

Back 409

O2; Glucose, Amino, and Fatty acids; CO2; H+; Hormones

Front 410

Blood flow is closely related to the _____ _____ of tissues.

Back 410

Metabolic rate

Front 411

What percentage of cardiac output is used by the tissues of the body?

Back 411

100%

Front 412

The _____ are the main site of variable resistance in the systemic circulation.

Back 412

Arterioles

Front 413

The _____ contribute more than 60% of the total resistance to flow in the system.

Back 413

Arterioles

Front 414

Resistance in the arterioles is variable because of the large amounts of _____ _____ in their walls.

Back 414

Smooth muscle

Front 415

When smooth muscle contracts and relaxes, the _____ of the arterioles changes.

Back 415

Radius or Diameter

Front 416

Arteriolar resistance is influenced by both _____ and _____ control mechanisms.

Back 416

Reflex; Vocal

Front 417

_____ _____ maintain mean arterial pressure (MAP) and govern blood distribution.

Back 417

Sympathetic reflexes

Front 418

_____ _____ matches flow to the metabolic needs of tissue.

Back 418

Local control

Front 419

_____ act directly on arterioles by altering autonomic reflex control.

Back 419

Hormones

Front 420

Increases in tissue _____ lead to increases in blood flow.

Back 420

Metabolism

(Acute control)

Front 421

Decreases in _____ availability to tissues increases tissue blood flow.

Back 421

Oxygen

Front 422

Oxygen availability decreases:
1. At _____ altitudes
2. In _____
3. _____ _____ poisoning – Hb can’t transport oxygen
4. _____ poisoning – Tissues unable to use oxygen

Back 422

High; Pneumonia; Carbon monoxide; Cyanide

Front 423

What are the two basic theories about how local blood flow is regulated when the rate of tissue metabolism changes or the availability of oxygen changes?

Back 423

Vasodilator Theory, Oxygen (Nutrient) Lack Theory

Front 424

Vasodilator theory:
_____ rate of metabolism or _____ availability of O2 causes an increased rate of formation of vasodilator substances (_____) in the tissue cells.

Back 424

Increased; Decreased; Paracrines

Front 425

In vasodilator theory, _____ diffuse through to precapillary sphincters, metarterioles and arterioles to cause _____.

Back 425

Paracrines; Dilation

Front 426

Paracrines that act as local vasodilators:
1. _____
2. _____ _____ compounds
3. _____ byproducts such as CO2, H+, K+, Lactic Acid

Back 426

Adenosine; Adenosine phosphate; Metabolic

Front 427

According to vasodilator theory, _____ concentrations change with _____ activity in the cells.

Back 427

Paracrine; Metabolic

Front 428

In vasodilator theory, not all vasoactive paracrines reflect changes in _____.

Back 428

Metabolism

Front 429

Kinins and histamine are potent vasodilators involved with _____.

Back 429

Inflammation

Front 430

Serotonin, released by activated platelets, triggers _____ to slow blood loss.

Back 430

Vasoconstriction

Front 431

In oxygen lack theory, oxygen (nutrients) is required for vascular (_____) _____ contraction.

Back 431

Sphincter; Muscle

Front 432

In oxygen lack theory, _____ of nutrients causes sphincter muscle to ‘relax’ and naturally _____.

Back 432

Absence; Dilate

Front 433

In oxygen lack theory, increased _____ would increase oxygen use and decrease its availability to the _____ _____, also causing local vasodilation.

Back 433

Metabolism; Sphincter muscle

Front 434

If _____ metabolism increases, tissue O2 levels decrease and CO2 levels increase.

Back 434

Aerobic

(Acute control)

Front 435

Low O2 and high CO2 _____ arterioles, increasing blood flow into the tissue and bringing in O2 to match _____ metabolic demand and remove CO2.

Back 435

Dilate; Increased

(Acute control)

Front 436

This process is called _____ _____; increased blood flow accompanies increased metabolic activity.

Back 436

Active hyperemia

(Acute control)

Front 437

In the process called active hyperemia; increased _____ _____ accompanies increased _____ activity.

Back 437

Blood flow; Metabolic

(Acute control)

Front 438

What process occurs if blood flow to tissue stops completely for a few seconds to minutes?

Back 438

Reactive hyperemia.

(Acute control)

Front 439

If blood flow to tissue stops completely for a few seconds to minutes, metabolically produced _____ (CO2, H+) accumulate in interstitial fluid.

Back 439

Paracrines

(Acute control)

Front 440

When flow resumes after being stopped, _____ concentration of paracrines immediately triggers significant _____.

Back 440

Increased; Vasodilation

(Acute control)

Front 441

When flow resumes after being stopped and flow washes away the _____ , the arteriole _____ gradually returns to normal.

Back 441

Vasodilators; Radius or Diameter

(Acute control)

Front 442

Any acute increase in arterial pressure causes an immediate rise in blood flow, but within _____ _____ flow normalizes though _____ _____ may stay elevated.

Back 442

One minute; Arterial pressure

(Autoregulation of blood flow)

Front 443

The return of flow towards normal is called _____ of blood flow.

Back 443

Autoregulation

Front 444

What are the 2 theories of autoregulation?

Back 444

Metabolic, Myogenic

Front 445

In the Metabolic Theory of _____, when _____ _____ becomes too great, excess flow provides too much O2 and other nutrients to tissues.

Back 445

Autoregulation; Arterial pressure

Front 446

In the Metabolic Theory of _____, The excess O2 and nutrients cause vessels to _____ and the flow returns almost to normal despite the _____ pressure.

Back 446

Autoregulation; Constrict; Increased

Front 447

In the Myogenic Theory of _____, _____ stretch of smooth muscle causes it to _____ for a few seconds.

Back 447

Autoregulation; Sudden; Contract

Front 448

In the Myogenic Theory of _____, When fibers in the _____ stretch due to increased BP, the _____ contracts and flow decreases back toward normal.

Back 448

Autoregulation; Arteriole; Arteriole

Front 449

In the Myogenic Theory of _____, At low BP the degree of stretch is less so smooth muscle _____ and allows _____ flow.

Back 449

Autoregulation; Relaxes; Increased

Front 450

In the Myogenic Theory of _____, The myogenic response is _____ to vascular smooth muscle and occurs in the _____ of neural or hormonal influences.

Back 450

Autoregulation; Inherent; Absence

Front 451

In the Myogenic Theory of _____, The myogenic response is most pronounced in _____ , but is observed in _____, _____, _____ and _____ vessels.

Back 451

Autoregulation; Arterioles; Arteries, venules, veins and lymphatic

Front 452

What occurs over hours, days and weeks when long-term changes in tissues occur?

Back 452

Long-term regulation of blood flow

Front 453

In long-term regulation of blood flow:
1. Sustained increases in _____ _____ occur
2. Sustained _____ increases in tissue occur

Back 453

Arterial pressure; Metabolic

Front 454

In long-term regulation of blood flow, the _____ and _____ of vessels change.

Back 454

Size; Number

Front 455

In long-term regulation of blood flow, _____ is an important stimulus for regulating tissue vascularity.

Back 455

Oxygen

Front 456

What is angiogenesis?

Back 456

Growth of new blood vessels

Front 457

Angiogenesis occurs in response to angiogenic factors released from:
1. _____ tissue
2. _____ growing tissue
3. Tissues with high _____ _____

Back 457

Ischemic; Rapidly; Metabolic rates

Front 458

Angiogenic factors include:
1. _____ _____ growth factor (VEGF)
2. _____ growth factor
3. _____

Back 458

Vascular endothelial; Fibroblast; Angiogenin

Front 459

Substances secreted or absorbed into the body fluids such as hormones or ions exert _____ control of the circulation.

Back 459

Humoral

Front 460

Some substances that exert humoral control of the circulation are _____ products that are transported via the circulation throughout the body.

Back 460

Gland

Front 461

Some substances that exert humoral control of the circulation are formed in _____and have local effects on circulation

Back 461

Tissues

Front 462

What are these substances?
Norepinephrine and Epinephrine
Angiotensin II
Vasopressin (ADH)
Endothelin
Serotonin

Back 462

Vasoconstrictors

Front 463

What are these substances?
Bradykinin
Histamine
Prostaglandins
Nitric Oxide

Back 463

Vasodilator agents

Front 464

Vasodilator agents may be released when _____ is damaged.

Back 464

Tissue

Front 465

What does all of these things?
Exit cord in all thoracic and L1, L2 spinal nerves
Enter the paravertebral chain ganglia
Goes to innervate the circulation via:
1. Specific sympathetic nerves to heart and viceral vasculature
2. Spinal nerves going to peripheral vasculature

Back 465

Sympathetic vasomotor fibers

Front 466

Sympathetic vasomotor fibers:
Exit cord in all _____ and L1, L2 spinal nerves
Enter the _____ _____ ganglia
Goes to innervate the circulation via:
1. Specific nerves to _____ and _____ vasculature
2. _____ nerves going to _____ vasculature

Back 466

Thoracic; Paravertebral chain; Heart; Visceral; Spinal; Peripheral

Front 467

Sympathetic stimulation _____ resistance and _____ flow in small arteries and arterioles.

Back 467

Increases; Decreases

Front 468

Sympathetic stimulation causes _____ to _____ volume, returning blood to the heart.

Back 468

Veins; Decrease

Front 469

What would cause all of these?
Marked increase in heart activity
Increasing the heart rate
Enhancing strength of pumping
Enhancing volume of pumping

Back 469

Sympathetic stimulation of the heart

Front 470

Sympathetic stimulation of the heart:
1. Marked _____ in heart activity
2. _____ the heart rate
3. Enhancing _____ of pumping
4. Enhancing _____ of pumping

Back 470

Increase; Increasing; Strength; Volume

Front 471

_____, carrying vasoconstrictor nerve fibers, innervate all vessels except _____, _____ sphincters and some _____.

Back 471

Sympathetics; Capillaries; Precapillary; Metarterioles

Front 472

Parasympathetics play a _____ role in regulation of circulation.

Back 472

Minor

Front 473

The most significant parasympathetic effect is the control of _____ _____ via parasympathetic nerve fibers in the _____ nerve going to the heart.

Back 473

Heart rate; Vagus

Front 474

Parasympathetic stimulation _____ heart rate and muscle contractility.

Back 474

Decreases

Front 475

Parasympathetic stimulation decreases _____ _____ and _____ _____.

Back 475

Heart rate; Muscle contractility

Front 476

What is located bilaterally in the reticular area of the medulla and lower pons?

Back 476

Vasomotor center (VMC)

Front 477

The vasomotor center (VMC) sends ____ impulses via cord and peripheral nerves to all _____, _____ and _____.

Back 477

Sympathetic; Arteries; Arterioles; Veins

Front 478

The vasomotor center (VMC) sends _____ impulses via the vagus nerve to the _____.

Back 478

Parasympathetic; Heart

Front 479

What is composed of these:
Vasoconstrictor area
Vasodilator area
Sensory area

Back 479

Vasomotor center (VMC)

Front 480

The vasomotor center (VMC) _____ area has neurons that become preganglionic fibers in the cord.

Back 480

Vasoconstrictor

Front 481

The vasomotor center (VMC) _____ area neurons project up to the vasoconstrictor area.

Back 481

Vasodilator

Front 482

The vasomotor center (VMC) _____ area receives sensory input from CN X and IX: output goes to the other 2 areas (‘reflex’ loop, ex. baroreceptor)

Back 482

Sensory

Front 483

The VMC vasoconstrictor area transmits signals continuously to sympathetic nerve fibers, this is _____ _____ _____.

Back 483

Sympathetic vasoconstrictor tone

Front 484

The VMC vasoconstrictor area transmits impulses that maintain a partial state of contraction in blood vessels is called _____ _____.

Back 484

Vasomotor tone

Front 485

_____ _____ of the VMC control heart activity by increasing heart rate and contractility.

Back 485

Lateral portions

Front 486

_____ _____ of the VMC signal the _____ _____ nucleus of the vagus, which then transmits parasympathetic impulses through the vagus to the heart to decrease heart rate and contractility.

Back 486

Medial portions; Dorsal motor

Front 487

The vasomotor center (VMC) can either increase or decrease _____ _____.

Back 487

Heart activity

Front 488

Heart rate and strength of contraction ordinarily increase with _____ and decrease with _____.

Back 488

Vasoconstriction; Vasodilation

Front 489

Reticular area:
Lateral and superior areas _____ the VMC
Medial and inferior areas _____ the VMC

Back 489

Excite; Inhibit

Front 490

What do these have in common?
Hypothalamus
Motor cortex
Anterior Temporal lobe
Frontal Orbital area
Anterior Cingulate Gyrus
Hippocampus
Amygdala

Back 490

These higher brain centers influence the vasomotor center (VMC)

Front 491

Vasoconstrictor nerves use _____ neurotransmitter that acts on _____ receptors

Back 491

Norepinephrine; α adrenergic

Front 492

The adrenal medulla secretes _____ and _____ into circulation and acts on α and β _____ receptors systemically to cause constriction (α) or dilation (β).

Back 492

Epinepherine; Norepinephrine; Adrenergic

Front 493

The nervous system can increase arterial pressure within seconds by:
1. _____ almost all arterioles of the body which increases total peripheral resistance
2. _____ large vessels of the circulation thereby increasing venous return and CO
3. Directly increases CO by increasing _____ _____ and _____

Back 493

Constricting; Constricting; Heart rate; Contractility

Front 494

Rapid increases in arterial pressure can occur during _____ or with extreme _____.

Back 494

Exercise; Fright

Front 495

Spray type nerve endings of baroreceptors are located in the walls of the _____ _____ and _____ _____.

Back 495

Carotid sinus; Aortic arch

Front 496

Baroreflex signals from the _____ _____ are transmitted by the Hering’s nerve to CN IX and then to _____ _____ and _____ of the medulla.

Back 496

Carotid sinus; Solitary tract; Nucleus (NTS)

Front 497

Baroreflex signals from the _____ _____ are transmitted through CN X into the _____ _____ and _____ of the medulla.

Back 497

Aortic arch; Solitary tract; Nucleus (NTS)

Front 498

_____ _____ receptors respond to pressures between ___ and ___ mmHg

Back 498

Carotid sinus; 60; 80

Front 499

Baroreceptor reflex is most sensitive at a pressure of ___ mmHg.

Back 499

100

Front 500

After baroreflex signals reach the solitary tract, secondary signals:
1. _____ the vasoconstrictor center
2. _____ the vagal parasympathetic center

Back 500

Inhibit; Excite

Front 501

Net effects of secondary baroreflex signals:
1. _____ of the veins and arterioles systemically
2. _____ heart rate and strength of contraction

Back 501

Vasodilation; Decreased

Front 502

Excitation of baroreceptors by high arterial pressure reflexively causes the arterial pressure to _____.

Back 502

Decrease

(Decrease in peripheral resistance and CO)

Front 503

The _____ _____ functions when you change position from lying to sitting to standing.

Back 503

Baroreceptor reflex

Front 504

What is the condition where, upon standing, gravity causes blood to pool in lower extremities causing arterial pressure to decrease.

Back 504

Orthostatic hypotension

Front 505

The baroreceptor reflex causes carotid and aortic receptors to _____ their firing rate causing an _____ in sympathetic activity.

Back 505

Decrease; Increase

(Increases in HR, force of contraction, peripheral resistance and CO )

Front 506

Orthostatic hypotension has minimal importance in _____ _____ control of arterial pressure.

Back 506

Long term

Front 507

_____ change in pressure causes _____ to reset in 1 to 2 days to the new pressure to which they are exposed.

Back 507

Chronic; Baroreceptors

Front 508

Interaction with other systems, specifically the _____ - _____ ______ - pressure control system, assists the baroreceptors in maintaining normal arterial pressure.

Back 508

Renal; Body fluid

Front 509

What are the chemosensitive cells that are sensitive to decreased O2 or increased CO2 and H+ levels?

Back 509

Chemoreceptors

Front 510

_____ receptors are located in the carotid bodies near the bifurcation and on the aortic arch.

Back 510

Chemosensitive

Front 511

Activation of chemosensitive receptors results in excitation of the _____ _____.

Back 511

Vasomotor center (VMC)

Front 512

Chemosensitive receptors are not stimulated until pressure falls below ___ mmHg.

Back 512

80

Front 513

_____ receptors found in _____ and _____ arteries minimize arterial pressure changes in response to changes in blood volume.

Back 513

Low-pressure; Atria; Pulmonary

Front 514

Increases in blood volume activate _____ receptors which then lower arterial pressure.

Back 514

Low-pressure

Front 515

Low-pressure receptors send sympathetics to the _____ and other centers:

Back 515

Kidney

Front 516

Low-pressure receptors sympathetic effects:
1. Hypothalamus _____ ADH secretion
2. _____ glomerular filtration rate
3. _____ water and sodium loss in urine

Back 516

Decreases; Increase; Increases

Front 517

What is the reflex by which an increase in atrial pressure also causes an increase in heart rate?

Back 517

Bainbridge reflex

Front 518

The Bainbridge reflex:
1. Stretch of _____ sends signals to _____ _____ via vagal afferents.
2. _____ _____ efferent signals via vagus and sympathetics to _____ heart rate and contractility
3. Prevents _____ of blood in veins, atria and the pulmonary circulation.

Back 518

Atria; Vasomotor center (VMC); Vasomotor center (VMC); Increase; Damming

Front 519

What is the response where CO2 buildup stimulates the sympathetic VMC area, causing an increase in systemic arterial pressure?

Back 519

Central nervous system (CNS) ischemic response

Front 520

In the CNS ischemic response, _____ buildup stimulates the _____ VMC area, causing an _____ in systemic arterial pressure.

Back 520

CO2; Sympathetic; Increase

Front 521

Arterial pressure elevation in response to cerebral ischemia is the _____ _____ _____.

Back 521

CNS ischemic response

Front 522

Degree of sympathetic _____ due to the _____ _____ _____ can be so great that some peripheral vessels become totally or almost totally occluded.

Back 522

Vasoconstriction; CNS ischemic response

(e.g., kidney ceases production of urine)

Front 523

What is one of the most powerful of all activators of the sympathetic vasoconstrictor system?

Back 523

Central nervous system (CNS) ischemic response

Front 524

The CNS ischemic response does not become significant until arterial pressure falls below ___ mmHg; greatest activation is at ___-___ mmHg

Back 524

60; 15-20

(“last ditch stand”)

Front 525

What is the special ischemic response due to increased cerebrospinal fluid (CSF) pressure?

Back 525

Cushing reaction

Front 526

The Cushing reaction:
1. _____ pressure rises to AP, compresses brain and arteries initiating _____.
2. _____ response causes AP to rise to higher level than _____
3. Helps to protect the vital centers of the brain from _____ and _____ loss

Back 526

CSF; Ischemia; Ischemic; CSF; O2; Nutrient

Front 527

Heart rate x Stroke volume = _____ _____

Back 527

Cardiac output (CO)

Front 528

What do these factors affect?
Basic level of body metabolism
Activity level (exercise)
Person’s age
Body size

Back 528

Cardiac output (CO)

Front 529

Average cardiac output:
1. _____ _____ = 5 L/min
2. _____ _____ _____ = 5.6 L/min
3. _____ = 4.9 L/min

Back 529

Resting adult; Young healthy male; Women

Hint 529

Male/Female/State involved

Front 530

What is the term that describes the various factors of the peripheral circulation affecting flow of blood into the heart from veins?

Back 530

Venous return

Front 531

What is the primary controller of cardiac output?

Back 531

Venous return

Front 532

The Frank-Starling Law states that the
heart pumps what flows into _____ _____.

Back 532

Right atrium

Front 533

Increased blood flow into the right atrium _____ muscle and the heart _____ with increased _____.

Back 533

Stretches; Contracts; Force

Front 534

Under most _____ _____ conditions, cardiac output is controlled almost entirely by peripheral factors that determine venous return.

Back 534

Normal unstressful

Front 535

(sinus node rate + ANS input) x (venous return + force of contraction) = _____ _____

Back 535

Cardiac output

Front 536

What is determined by the sum of all various factors that control local blood flow systemically?

Back 536

Cardiac output

Front 537

All local blood flows summate to form the _____ _____.

Back 537

Venous return

Front 538

Stroke volume increases as _____ volume increases.

Back 538

End-diastolic

(Frank-Starling law)

Front 539

What is end-diastolic volume determined by?

Back 539

Venous return

(Frank-Starling law)

Front 540

What do these factors affect?
1. Contraction / compression of veins returning blood to heart (skeletal muscle pump)
2. Pressure changes in the abdomen and thorax during breathing (respiratory pump)
3. Sympathetic innervation to veins

Back 540

Venous return

Front 541

Factors affecting venous return:
1. Contraction / compression of _____ returning blood to heart (skeletal muscle pump)
2. _____ changes in the abdomen and thorax during breathing (respiratory pump)
3. _____ innervation to veins

Back 541

Veins; Pressure; Sympathetic

Front 542

Under most normal conditions, long-term CO level varies _____ with changes in total peripheral resistance (TPR).

Back 542

Reciprocally

(TPR increases, CO decreases and vice versa)

Front 543

There are limits to how much blood the heart can pump, which can be expressed quantitatively in the _____ _____ curves.

Back 543

Cardiac output

Front 544

In the normal heart, the plateau of ___ L/min is ___x the normal CO of 5 L/min.

Back 544

13; 2.5

Front 545

The heart can pump an amount of venous return up to ~ ___x before the heart becomes a _____ factor in control of CO.

Back 545

2.5; Limiting

Front 546

What do these factors cause?
1. Nervous stimulation of the heart
2. Hypertrophication of the heart muscle

Back 546

The heart becoming a better (stronger) pump.

Front 547

_____ stimulation and _____ inhibition increases pumping effectiveness by:
1. Increasing the HR
2. Increasing strength of heart contraction (“contractility”)

Back 547

Sympathetic; Parasympathetic

Front 548

Combining sympathetic and parasympathetic effects can raise the _____ level of the CO curve to almost _____ that of normal.

Back 548

Plateau; Twice

Front 549

A long-term increased workload, but not excessive, causes an increase in muscle mass and contractile strength. This is called _____.

Back 549

Hypertrophication

(e.g., from marathon running)

Front 550

The total effect of combining _____ _____ of the heart and _____, allows the heart to pump about 2.5x normal.

Back 550

Nervous excitation; Hypertrophy

Front 551

What effect do these have?
Coronary artery blockage (MI, heart attack)
Inhibition of nervous excitation of the heart
Pathological factors causing abnormal rhythm or rate
Valvular heart disease
Increased arterial pressure ; Hypertension
Congenital heart disease
Myocarditis

Back 551

Decreased ability of the heart to pump blood

Front 552

What do these factors affect?
1. Right atrial pressure that exerts backward pressure force on veins impeding flow into the right atrium
2. Degree of filling of the systemic circulation which forces blood toward heart (mean systemic filling pressure)
3. Resistance to blood flow between the peripheral vessels and the right atrium

Back 552

Venous return

(Principle factors)

Front 553

Factors affecting venous return:
1. Right atrial pressure that exerts _____ pressure force on veins impeding flow into the right atrium
2. Degree of filling of the _____ circulation which forces blood toward heart (mean _____ filling pressure)
3. _____ to blood flow between the peripheral vessels and the right atrium

Back 553

Backward; Systemic; Systemic; Resistance

Front 554

The venous return curve relates venous return to the _____ _____ pressure.

Back 554

Right atrial

Front 555

_____ _____ into the heart is affected by right atrial pressure.

Back 555

Venous return

Front 556

When heart pumping capability is _____, the right atrial pressure rises and the _____ force of this rising pressure decreases venous return.

Back 556

Diminished or Decreased; Backward

Front 557

_____ _____ would be zero when the right atrial pressure rises to _____ the mean systemic filling pressure.

Back 557

Venous return; Equal

Front 558

At the same time the right atrial pressure is _____ causing venous stasis, pumping by the heart also approaches zero because of _____ venous return.

Back 558

Rising or Increasing; Decreasing

Front 559

Both arterial and venous pressures come to _____ when all flow in the systemic circulation ceases.

Back 559

Equilibrium

(mean systemic filling pressure = 7 mmHg)

Front 560

When right atrial pressure falls below ___ mm Hg further increase in venous return ceases.

Back 560

0

(atmospheric pressure)

Front 561

_____ in the curve is caused by the _____ of the large veins entering the chest, preventing additional flow from peripheral veins.

Back 561

Plateau; Collapse

Front 562

Most resistance to _____ _____ occurs in the veins, though some occurs in the arterioles and small arteries as well.

Back 562

Venous return

Front 563

When resistance in veins _____, blood begins to be dammed up, mainly in the veins themselves.

Back 563

Increases

Front 564

As veins are highly _____ the rise in venous pressure is small, and _____ effective in overcoming resistance, and flow into the atrium _____ drastically.

Back 564

Distensible; Not; Decreases

Front 565

When _____ increase in arteries and arterioles, blood accumulates, but the _____ is much smaller than that of the veins.

Back 565

Resistances; Capacitance

Front 566

A slight accumulation of blood in arteries _____ the pressure greatly, and this pressure change does overcome much of the increased _____.

Back 566

Raises or Increases; Resistance

Front 567

Decrease in _____ to ½ normal allows 2x as much flow

Back 567

Resistance

Front 568

_____ in resistance to 2x normal decreases flow to half that of normal

Back 568

Increase

Front 569

When right atrial pressure equals mean systemic filling (Psf) pressure, flow is _____.

Back 569

Zero

Front 570

Sympathetic stimulation makes the heart a _____ pump.

Back 570

Stronger

Front 571

In the systemic circulation, what increases the mean systemic filling pressure because of contraction of the peripheral vessels and increases the resistance to venous return?

Back 571

Sympathetic stimulation

Front 572

In the systemic circulation sympathetic stimulation _____ the mean systemic filling pressure because of contraction of the peripheral vessels and it _____ the resistance to venous return

Back 572

Increases; Increases

Front 573

Increased _____ _____ increases CO and venous return curves. This can be maintained for _____ periods of time until other compensatory effects occur in seconds to minutes.

Back 573

Sympathetic stimulation; Short

Front 574

With _____ blood flow can increase from 3 - 4 ml/min to 50 to 80 ml/min in skeletal muscle.

Back 574

Exercise

Front 575

Metabolic demand _____ flow.

Back 575

Increases

Front 576

Contracting muscle _____ flow transiently by compressing vessels.

Back 576

Decreases

Front 577

With continued activity, other metabolic byproducts (paracrines) maintain increased _____ and _____ flow.

Back 577

Vasodilation; Capillary

Front 578

Decreased O2 concentration in muscle due to activity results in local _____.

Back 578

Vasodilation

Front 579

What are these?
K+ ions
ATP
Lactic Acid
CO2

Back 579

Metabolic byproducts (paracrines)

Front 580

ANS-controlled redistribution of blood flow results from a combination of _____ in skeletal muscle arterioles and _____ in other tissues.

Back 580

Vasodilation; Vasoconstriction

Front 581

Paracrines cause local _____ that overrides the sympathetic signal for _____, resulting in shunting of blood flow from _____ to _____ tissues.

Back 581

Vasodilation; Vasoconstriction; Inactive; Active

(ANS)

Front 582

What are these effects?
1. Mass discharge of sympathetic nervous system through body with consequent stimulatory effects on entire circulation
2. Increase in arterial pressure
3. Increase in cardiac output

Back 582

Effects of exercise on the circulatory system

Front 583

Effects of exercise:
1. Mass discharge of _____ nervous system through body with consequent stimulatory effects on entire circulation
2. _____ in arterial pressure
3. _____ in cardiac output

Back 583

Sympathetic; Increase; Increase

Front 584

With onset of _____ there are multiple inputs to activate the vasomotor control center in the medulla resulting in _____ discharge.

Back 584

Exercise; Sympathetic (norepinephrine)

Front 585

What causes these effects?
1. Heart rate and pumping strength increase
2. Peripheral arterioles contract except those in active muscle, which are dilated
3. Veins are contracted which increases the mean systemic filling pressure, increasing venous return and CO

Back 585

Sympathetic discharge

Front 586

Sympathetic discharge effects:
1. Heart rate and pumping strength _____
2. Peripheral arterioles _____, except those in active muscle, which are _____
3. Veins are contracted which _____ the mean systemic filling pressure, _____ venous return and CO

Back 586

Increase; Contract; Dilated; Increases ; Increasing

Front 587

Depending on the type of exercise, the arterial pressure can rise as little as ___ mmHg or as high as ___ mmHg.

Back 587

20; 80

Front 588

Whole body exercise shows _____ increase in CO because extreme _____ occurs simultaneously in large muscle groups.

Back 588

Small; Vasodilation

Front 589

_____ _____ is enhanced by skeletal muscle contraction and inspiration (respiratory pump).

Back 589

Venous return

Front 590

_____ of ventricles is prevented by increasing the heart rate; giving the heart less time to fill and decreasing likelihood of fiber damage.

Back 590

Overfilling

Front 591

During _____, parasympathetic activity at the sinus node is decreased and sympathetic output from cardiovascular control center esclates.

Back 591

Exercise

Front 592

During _____, sympathetic input increases contractility and HR, increasing cardiac output.

Back 592

Exercise

Front 593

What rises because of these?
1. Increased mean systemic filling pressure
2. Decreased resistance to venous return in active tissues

Back 593

Venous return curve

Front 594

Venous return curve rises during:
1. _____ mean systemic filling pressure
2. _____ resistance to venous return in active tissues

Back 594

Increased; Decreased

Front 595

Normal _____ blood flow at rest averages 225 ml/min or 4-5% or total cardiac output.

Back 595

Coronary

Front 596

_____ exercise increases CO, pumps against higher arterial pressure, and _____ blood flow increases _____- to _____fold to supply increased energy needs of the cardiac muscle.

Back 596

Strenuous; Coronary; Three; Four

Front 597

Because the heart contracts during strenuous exercise, blood flow during systole _____ and during diastole blood flows rapidly in the _____ vessels.

Back 597

Decreases; Coronary

Front 598

Local flow is regulated by local arteriolar _____ in response to metabolic demands (primarily O2) of the cardiac tissue.

Back 598

Vasodilation

Front 599

Decreased heart activity is accompanied by decreased _____ blood flow.

Back 599

Coronary

Front 600

____ stimulation slows heart, decreases contractility and rate of metabolism. The result is indirect constriction of _____ arteries.

Back 600

Vagus; Coronary

(ANS)

Front 601

_____ stimulation of _____ vessels increases HR, contractility and rate of metabolism. The result is indirect dilation of _____ vessels.

Back 601

Sympathetic; Coronary; Coronary

(ANS)

Front 602

How does the ANS directly affect vasculature?

Back 602

Neurotransmitters

Front 603

_____ stimulation (vagus, (ACh) has a direct effect to dilate the coronary arteries.

Back 603

Parasympathetic

(ANS)

Front 604

_____ stimulation (epi- or norepinephrine) can vasoconstrict or vasodilate depending on the receptor activated. α receptors ____; β receptors ____

Back 604

Sympathetic; Constrict; Dilate

(ANS)

Front 605

_____ factors – especially myocardial _____ consumption – are the major controllers of myocardial blood flow.

Back 605

Metabolic; O2

Front 606

Whenever the direct ANS effects alter _____ blood flow in “the wrong direction”, the _____ control of _____ flow usually overrides the direct ANS effects within seconds.

Back 606

Coronary; Metabolic; Coronary

Front 607

Respiratory system processes:
1. Pulmonary _____
2. _____ of O2 and CO2 between alveoli and blood
3. _____ of O2 and CO2 in the blood and body fluid
4. _____ of Ventilation

Back 607

Ventilation; Diffusion; Transport; Regulation

Front 608

Calculation of lung zone 2 flow:
_____: 25-15 = 10 > 0
_____: 8-15 = -7 < 0

Back 608

Systole; Diastole