BIOL 322-Chapter 12: Cardiovascular Physiology
Match the letters on the figure with the correct name of the structure of the cardiac conduction system.
(KNOW THE DIAGRAM) A- Sinoatrial node B- Atrioventricular node C- Bundle of His D- Purkinje fibers within the ventricle wall E- Left bundle branch F- Right bundle branch
The ejection of blood from the ventricles mainly occurs during the segment of the figure indicated by the letter _______.
(KNOW THE DIAGRAM) B
In the figure, the tricuspid valve is indicated by the letter _______ and the bicuspid valve is indicated by the letter _______.
(KNOW THE DIAGRAM) C and D
In the figure, the pacemaker potential is indicated by the letter _______.
(KNOW THE DIAGRAM) D
In the figure, the phase of rapid filling of the ventricles is indicated by the letter ________.
(KNOW THE DIAGRAM) D
In the figure, atrial systole is indicated by the letter __________.
(KNOW THE DIAGRAM) E
The AV valves are prevented from opening backwards into the atria by the papillary muscles ___________ pulling on the chordae tendineae __________ attached to the valve flaps.
(KNOW THE DIAGRAM) E and B
Match the ECG leads with the letters on the figure.
(KNOW THE DIAGRAM) E- Lead 2 F- Lead 3 G- Lead 1
In the figure, the pulmonary semilunar valve is indicated by the letter ________ and the aortic semilunar valve is indicated by the letter _________.
(KNOW THE DIAGRAM) W and Y
What principle of cardiovascular regulation is demonstrated by this figure?
(KNOW THE DIAGRAM) When arterioles in one systemic organ dilate, mean arterial blood pressure is maintained by compensatory constriction of arterioles in other organs
A technique for studying heart function which involves beaming ultrasonic waves at the heart and recording the returning sounds is known as _________.
echocardiography
When cells of the cardiac conduction system other than the SA node manifest their own rhythm it is called a(n) _______ pacemaker.
ectopic
Dividing the cardiac stroke volume by the end-diastolic volume yields a quantity called the __________, which is one measure of the cardiac contractility.
ejection fraction
The function of the atrioventricular valves is to
ensure that the flow of blood in the heart is one-way, from the atrium to the ventricle on each side
The "trigger" Ca2+ that is part of the cardiac excitation-contraction coupling mechanism _______.
enters the cell from the extracellular fluid through L-type Ca2+ channels, enters the cell during the plateau phase of the action potential
Activation of the sympathetic branch of the autonomic nervous system ________ the slope of the pacemaker potential in SA node cells by increasing _______ current.
increases and Na+
The phase of the cardiac cycle that immediately follows the closing of the semilunar valves is the ________.
isovolumetric relaxation phase
The point at which oxygen consumption can no longer increase even if workload increases is known as ________.
maximal oxygen consumption
During exercise, increases in heart rate are mediated by decreased activity of the _________ nervous system, and partly by increased activity by the __________ nervous system.
parasympathetic and sympathetic
In the equation that approximates mean arterial pressure, one-third of the ________ is added to the diastolic pressure.
pulse pressure
The ventricular contraction phase of the cardiac cycle is called _______, and the ventricular relaxation phase is called _______.
systole and diastole
Under steady conditions (such as in a person that is sitting quietly in a chair for a prolonged period), venous return is _______ cardiac output.
the same value as
At venous return fills the ventricles with more blood and cardiac muscle is stretched from a short length to a longer length, _______.
the sensitivity of troponin for binding Ca2+ increases
The return of systemic venous blood through the inferior vena cava of a person in the standing position is facilitated by _______.
the skeletal muscle pump, venous valves, and breathing
The average vascular pressure at the beginning of a systemic capillary is greater than _________.
the systolic pressure in a pulmonary artery
The gradients for diffusion of oxygen, carbon dioxide, and glucose across tissue capillary walls is ultimately determined by ___________.
the tissue metabolic rate
What changes occur to the ventricular muscle contractions as a result of sympathetic stimulation?
Tension reaches a greater value, Tension increases faster, Contractions become briefer
An increased arterial pressure tends to reduce stroke volume. The term used to describe how hard the heart must work to eject blood during contraction is _______.
afterload
When the ventricles contract, and the pressure in each ventricle exceeds the pressure in each atrium, the AV valves _______.
close, so that blood does not flow backwards into each atrium
When the pressure in the pulmonary trunk exceeds the pressure in the right ventricle, the pulmonary semilunar valve ________.
closes
The strength of ventricular muscle contraction at any given end-diastolic volume is termed _______.
contractility
According to the Frank-Starling law of the heart, when the end-diastolic volume increases the ________ increases.
contraction force
What changes occur to ventricular muscle contractions as a result of sympathetic stimulation?
Contractions become briefer, Tension increases faster, Tension reaches a greater value
In an ECG, the P wave represents _________.
depolarization of the atria
Contraction of the _______ during breathing creates a pressure gradient that favors movement of blood from abdominal veins to thoracic veins.
diaphragm
The minimum pressure in systemic arteries, which occurs right before ventricular ejection begins, is known as the _________ blood pressure.
diastolic
The net transport of nutrients and wastes across capillary walls occurs predominately by ________.
diffusion
The volume of blood in each ventricle at the conclusion of the filling phase, immediately before the ventricles begin to contract, is called the ________ volume.
end diastolic
The amount of blood remaining in each ventricle following systole is called the ________.
end-systolic volume
The end-diastolic volume minus the stroke volume equals the ________.
end-systolic volume
Which of the following are true of atrial systole?
The ventricles are in diastole, It adds a small amount of extra volume to the ventricles
In cardiac muscle, the duraction of the action potential is _________ the duration of the contraction.
nearly the same as
Match each letter in the model system with the systemic vascular circuit variable it best represents.
(KNOW THE DIAGRAM) A- Blood flow to organs B- Arteriolar resistance C- Arterial pressure
Which letter indicates the normal pacemaker of the heart?
(KNOW THE DIAGRAM) E
List these steps in the cause-and-effect order that they link a decrease in blood volume (like a hemorrhage) to decreased arterial blood pressure.
1) Decreased venous pressure 2) Decreased venous return 3) Decreased atrial pressure 4) Decreased ventricular end-diastolic volume 5) Decreased stroke volume 6) Decreased cardiac output
In which of these pairs is the first quantity significantly greater than the second?
1. The pressure inside a foot capillary when standing 2. The pressure inside a foot capillary when lying down
Without any autonomic or hormonal influences, the heart would beat at a rate of approximately _____.
100 bpm
If a patient's systolic blood pressure is 130 mmHg and her diastolic pressure is 100 mmHg, what is the best approximation of her mean arterial blood pressure.
110 mmHg
Decreasing the radius of a tube by half will decrease the flow by a factor of _________.
16
In a patient with severe, untreated AV conduction disorder, the frequency of ventricular beating is generally in the range of ________.
25-40 beats per minute
Which of the following most likely represents the cardiac output of an athlete during strenuous exercise?
35 L/min
Cardiac output at rest in an average size person is about _________ liters per minute.
5-6
If the stroke volume is 50mL and the end-systolic volume is 15mL, the end-diastolic volume is ______ mL.
65
Which of these best describes how osmosis influences capillary bulk flow?
A concentration gradient for non-penetrating solutes across capillary walls causes net movement of water and penetrating solutes by bulk flow
The beginning of ventricular systole is marked by the first heart sound, corresponding to the closing of the ________ valves, and the beginning of ventricular diastole is marked by the second heart sound, corresponding to the closing of the ________ valves.
AV and semilunar
Which is the term for a condition in which some action potentials spreading through the atria fail to propagate into the ventricles?
AV conduction disorder
Organize the steps which lead to contraction of cardiac muscle.
Action potentials propagate along cell membranes, Cytoplasmic Ca2+ concentrations increase, Cross-bridges form, Force is generated
A decrease in which one of the following would cause an increase in cardiac output?
Activity of parasympathetic nerves to the heart
Which best describes the relationship between arterial blood pressure and action potential firing by the arterial baroreceptors?
An increase from normal pressure causes increased action potential frequency and decreased pressure causes decreased action potential frequency
Which correctly describes pressure gradients during the mid-to-late diastolic phase of the cardiac cycle?
Aortic pressure is greater than left atrial pressure, which is greater than left ventricular pressure
Which blood vessels are most influential in varying the blood flow through individual organs?
Arterioles
Which of these are sometimes the result of prolonged hypertension?
Atherosclerosis, Stroke, Heart Attack and Ventricular Hypertrophy
In which of the following conditions do the atria fall to contract rhythmically and in synchrony?
Atrial fibrillation
Which explains why heart muscle cannot undergo the kind of tetanic contractions that occur in skeletal muscle?
Because of the long action potential and the resultant long absolute refractory period in cardiac muscle.
Hemodynamics is the study of factors determining what three aspects of the circulatory system?
Blood flow, Blood pressure, and Resistance to blood flow
Filtration is __________ Absorption is _________
Bulk flow occurring from the plasma into the interstitial fluid Bulk flow occurring from the interstitial fluid into the plasma
_________ are a type of blood vessel in which the walls consist of a single endothelial cell layer resting on a basement membrane, without any surrounding smooth muscle or elastic tissue.
Capillaries
Which of the following chemical factors INCREASE in the extracellular fluid surrounding arterioles to mediate the process of active hyperemia?
Carbon Dioxide, K+, Nitric Oxide, and Adenosine
Heart sounds, typically described as "lub-dup", are associated with what cardiac events?
Closing of the AV and semilunar valves
Which correctly describe effects of parasympathetic nerve firing on cardiac action potential conduction velocity?
Conduction velocity through the AV node decreases, Conduction velocity in the atria decreases
Which correctly describe the structure and functions of veins?
Contain valves that permit flow only toward the heart, Contraction increases the rate of return of blood to the heart, Low-resistance conduits for return to blood to the heart
Which of these helps maintain effective circulating blood volume in a person who is standing upright?
Contraction of skeletal muscles in the legs
Which of the following stimuli would lead to an increase in arterial blood pressure?
Decreased arterial O2 levels, Decreased blood flow to the brain, and Increased arterial CO2 levels
Which electrical event causes the deflection known as the QRS complex in an ECG recording?
Depolarization of the ventricles
A record of the potential differences generated by the heart and conducted via body fluids to the surface, where it is detected by electrodes, is called a(n) ___________ recording.
ECG
In a given capillary bed, the hydrostatic pressure in the interstitial fluid is 3mmHg, the protein oncotic pressure in the plasma is 26 mmHg, the capillary blood pressure is 37 mmHg at the arterial end and 15 mmHg at the venous end, and there are no non-penetrating solutes or proteins in the interstitial fluid. Under these conditions here will be ________ at the arterial end of capillaries, ________ at the venous end of capillaries, and overall ________.
Filtration, Absorption, There will be net fluid absorption
The relationship between stroke volume and end-diastolic volume is known as the _________ mechanism after the two scientists who originally described it.
Frank-Starling
In which three of these organs is flow auto-regulation a critical determinant of arteriolar function?
Heart, Brain, and Kidneys
With normal, healthy aging, systolic pressures tend to become ________ and diastolic pressures tend to become ________.
Higher and Lower
Match the type of shock with its cause.
Hypovolemic is hemorrhage Cardiogenic is heart attack Low-Resistance is allergic reaction
Which four of the following contribute to increased venous return during exercise?
Increased respiratory pump activity, Increased ease of blood flow from arteries to veins, Increased skeletal muscle pump activity, Increased venous tone
Which of the following is NOT a mechanism involved in generating the pacemaker potential portion of an SA node cell action potential?
Influx of Ca2+ through L (long-lasting) type channels
Rapid repolarization of myocardial cells occurs as ________ diffuses ________.
K+ and out
Inward current that maintains depolarization during the plateau of a cardiac myocyte action potential flows through which ion channels?
L-type Ca2+ channels
Rank the capillaries in following tissues from leakist to least leaky.
Liver, Skeletal Muscle, Brain
Which of these is a paracrine vasodilator secreted by vascular endothelial cells?
Nitric oxide
Put these tissue layers of the heart in order from outside at the top to inside at the bottom.
Pericardium, Epicardium, Myocardium, Endothelium
The cardiac cells that form a branching network that rapidly spreads excitation throughout the ventricles are called _______.
Purkinje fibers
In a normal heart, the initial depolarization arises in the region known as the _______.
SA node
In an ECG, the repolarization of the ventricles is recorded as the __________ wave.
T
Select the TRUE statements about blood flow during ventricular systole and diastole of a single cardiac cycle.
The amount of blood flowing from arteries into arterioles is greater in ventricular diastole than in systole, The blood volume leaving arteries in systole plus the volume leaving arteries in diastole equals the volume ejected from the heart in systole, The amount of blood ejected from the heart in systole is greater than the amount of blood leaving the arteries in systole
Which correctly describes the cardiac valves during the mid-to-late diastolic phase of the cardiac cycle?
The atrioventricular valves are open and the semilunar valves are closed
List these events in the order that they occur as the ventricular systole phase of the cardiac cycle begins.
The depolarization wave passes from the AV node through the ventricles, producing the QRS wave of the ECG recording, The ventricles begin to contract and the pressure begins to increase, The AV valves close, The first heart sound ("Lub") occurs, Pressure in the ventricles increase toward the pressure in the aorta and pulmonary trunk, The semilunar valves-open and blood is rapidly ejected from the ventricles
What causes the venous pulse that can be seen in the neck during atrial contraction?
The lack of valves between superior vena cava and right atrium allows a small backward flow of blood.
Which three factors underlie the increase in force of cardiac muscle when it is stretched to longer lengths?
The overlap of thick and filaments allows more cross-bridges to bind, Reduced spacing between thick and thin filaments increases cross-bridge binding, More Ca2+ is released from the sarcoplasmic reticulum
Which best describes the timing of heart chamber contractions in its function as a "dual pump"?
The two atria contract simultaneously, pumping blood into the two ventricles, which then contract simultaneously.
True or false: Approximately 1% of cardiac cells do not function in contraction, but are specialized to spread excitation rapidly throughout the heart.
True
True or false: There are no valves separating the venae cavae from the right atrium.
True
Isovolumetric relaxation occurs _______.
When all valves are closed and the ventricles contain the end-systolic volume of blood, in association with the second heart sound ("dup"), when pressure in the aorta and pulmonary trunk is higher than that in the ventricles, which has closed the semilunar valves
In the cardiac cycle, rapid filling of the ventricles occurs ________.
When ventricular pressure decreases to become lower than atrial pressure, When the AV valves open
Shock is a general clinical term describing a situation in which _______.
a decrease in organ and tissue blood flow results in damage
Interstitial fluid enters lymphatic capillaries primarily via ________.
bulk flow
Lower than normal blood pressure is called _________.
hypotension
Ejection of blood from the left ventricle occurs _________.
when pressure in the left ventricle exceeds pressure in the aorta, when the aortic semilunar valve is open
This figure shows a voltage versus time plot of the action potential of what type of cardiac cell?
(KNOW THE DIAGRAM) Node Cell
Which two of the following will result in an increase in the stroke volume during a given cardiac cycle?
A decrease in the afterload, An increase in sympathetic nerve stimulation
What are the three main determinants of systemic arterial pulse pressure?
Arterial compliance, Speed of ejection of the stroke volume, and Stroke volume
What events occur at the beginning of ventricular systole?
The AV valves close, The first heart sound occurs ("Lub"), The QRS complex of the ECG, Ventricular pressure increases above atrial pressure
Beta-adrenergic receptor stimulation of cardiac myocytes result in ______.
Phosphorylation of thin filament proteins, An increase in the amount of Ca2+ released from the sarcoplasmic reticulum, An increase in cAMP concentration in the cell, An increase in trigger Ca2+ entering through L-type Ca2+ channels
Which of the following describes atrial fibrillation?
Disorganized electrical activity in the atria that prevent them from working as effective pumps
In an ECG, the depolarization of the ventricles is represented by the ________ complex.
QRS
The ratio of the stroke volume to end-diastolic volume of the heart is called the ________.
conjunction junction
Norepinephrine acts on cardiac muscle to increase the strength of contraction at any given end-diastolic volume. This change is referred to as an increase in ______.
contractility
What event is represented by the T wave on the ECG recording?
Ventricular repolarization
Which of the following determine the resistance to flow of a fluid through a tube?
Viscosity of the fluid, Length of the tube, Radius of the tube
A technique for studying heart function which involves injecting a contrasting liquid into blood vessels and imaging the vessels with x-rays is cardiac _________.
angiography
The stiffening of arteries that occurs with age is called ________.
arteriosclerosis
The volume of blood in the ventricles is highest ________.
at the end of ventricular diastole
"Local controls" by which organs and tissues alter their own arteriolar resistances and blood flow include _________.
autocrine substances and paracrine substances
The capacity for spontaneous, rhythmic self-excitation in cardiac muscle is referred to as ________.
automaticity
Mean systemic arterial blood pressure is the product of total peripheral resistance and _______.
cardiac output
The amount of blood ejected by the left ventricle every minute is called the _______.
cardiac output
The first heart sound ("lub") is associated with ________.
closing of the AV valves
When measuring blood pressure with a sphygmomanometer, when pressure in the blood-pressure cuff is between a person's diastolic and systolic pressures _________.
intermittent sounds associated with turbulent blood flow are heard through the stethoscope
The process by which a change in blood pressure to an organ initiates mechanisms that lead to a change in arteriolar resistance in that organ is known as _________.
flow autoregulation
In the absence of any autonomic or hormonal influences, the heart rate would be ________ then it normally is at rest.
higher
Afterload refers to ______.
how hard the heart needs to work to eject blood against arterial blood pressure
If a person has a resting blood pressure above 140 systolic pressure and 90 diastolic, their condition would be diagnosed as _______.
hypertension
The treatment for severe AV conduction disorders is __________.
implantation of an artificial pacemaker
Sympathetic neuron activation ________ the velocity of action potential conduction in the heart.
increases
Activation of the sympathetic branch of the autonomic nervous system _________.
increases the heart rate
The amount of blood that enters the atria each minute is called the ________, which in the steady state is the same quantity as the cardiac output.
venous return
The AV valves open and close as a result of ________.
pressure differences between the atria and ventricles
Vasodilation and increased tissue blood flow following a period of complete occlusion of its blood supply is called ____________.
reactive hyperemia
Some situations result in a body-wide a decrease in blood flow to organs and tissues that results in tissue damage, such as low blood volume, decreased total peripheral resistance, or failure of the heart to pump. The general clinical term for these situations is _______.
shock
Heart sounds are detected using a(n) ________.
stethoscope placed on the chest
According to the Frank-Starling law of the heart, when the end-diastolic volume increase the _________ increases.
stroke volume
Heart rate x ______ = cardiac output
stroke volume
The amount of blood that the ventricle ejects during each beat is called the ____________.
stroke volume
The second heart sound ("dup") is associated with _________.
the closing of the semilunar valves, the T wave of the ECG
Slow propagation of action potentials through the AV node is responsible for _______.
the delay between contraction of the atria and contraction of the ventricles
Quiet, smooth blood flow that does not cause vibrations of blood vessels or the heart is termed _______ flow.
laminar
As compared to arteries, the hydrostatic pressure exerted by blood on the walls of veins is ________.
lower
The pressure in the pulmonary arterial circulation is ______ compared to the systemic arterial circulation.
lower
Baroreceptor reflex afferents influence the cardiovascular control center located in the region of the brain known as the _______.
medulla oblongata
The systemic arterial baroreceptor afferent inputs are integrated in the _______.
medulla oblongata
Another name for the left atrioventricular valve is the ___________ valve.
mitral
Blood pressure is measured in units of _______.
mmHg
A blood vessel with high compliance can be stretched ________ than a blood vessel with low compliance
more easily
The parasympathetic nervous system results in activation of _______ receptors on heart cells, and the sympathetic nervous system results in activation of _______ receptors on heart cells.
muscarinic-ACh and beta-adrenergic
Sympathetic innervation of the heart occurs via release of the neurotransmitter _____________ by postganglionic fibers, and the release of ___________ by the adrenal medulla.
norepinephrine and epinephrine
The portion of cardiac action potentials called the pacemaker potential _______.
occurs in sinoatrial (SA) node cells, triggers cardiac action potentials, automatically depolarizes independently of the nervous system
When right and left atrial pressures exceed right and left ventricular pressures, respectively, the AV valves ___________.
open, and blood flows from the atria to the ventricles
When the pressure in the ventricles exceeds the pressure in the aorta and pulmonary trunk, the semilunar valves ___________.
open, and blood flows from the ventricles into the arteries
Normally, prolapse of the AV valves and backflow of blood from the ventricles into the atria is prevented by the contraction of the _______, which pull(s) on the _______ attached to each valve.
papillary muscles and chordae tendineae
The volume of blood in the ventricles immediately before contraction correlates to the stretch of the heart, which is termed ______.
preload
A key difference between cardiac and skeletal muscle is that ________.
the number of skeletal muscle cells that contract can be varied, while every heart cell contracts with every contraction
Cardiac output is equal to _________.
the product of stroke volume and heart rate
The reason why the absolute refractory period is much longer in skeletal muscle than in cardiac muscle is ________.
the prolonged plateau phase of the cardiac action potential
Because the walls of veins have _______ compliance, they can accommodate a relatively _______ volume of blood with a relatively ________ increase in internal pressure.
high, large, and small
Stimulation of beta-adrenergic receptors in cardiac myocytes alters contraction speed and strength by ________.
activating a second-messenger cascade involving cAMP
In skeletal muscles, an increase in blood flow caused by increased metabolism is called _________.
active hyperemia
With each cardiac cycle, contraction of the ventricles ejects ________.
an amount of blood referred to as the stroke volume
Circulatory System (cardiovascular system) is made up of the
heart, blood, blood vessels, and the vascular system
This is a plot of membrane ion permeability versus time for a ventricular muscle cell. Match the letter of each curve in the figure to the correct ion.
(KNOW THE DIAGRAM) A- Potassium ion permeability B- Sodium ion permeability C- Calcium ion permeability
True or False: Conductions defects that eliminate the atria as effective pumps, such as atrial fibrillation, seriously impair ventricular filling.
False
True or false: Because cardiac muscle must contract continuously throughout life, some cells are not activated during heart beats that occur when a person is at rest.
False
True or false: During the spread of depolarization through the heart, excitation passes directly from atrial muscle cells to ventricular muscle cells through gap junctions.
False
True or false: Metabolic waste products from myocardial cells diffuse mainly into the blood within the heart's chambers.
False
True or false: The typical cardiac output in a resting adult is about 20-25 L/min.
False
True or false: When norepinephrine from sympathetic neurons binds to beta-2 adrenergic receptors on arteriolar smooth muscle, vasoconstriction occurs.
False
Which of these correctly describe the relationship between blood volume and arterial blood pressure?
Increased arterial blood pressure activates mechanisms that reduce blood volume and Increasing blood volume causes an increase in arterial blood pressure
Which of the following would cause an increase in cardiac output?
Increased end-diastolic ventricular volume, Increased activity of sympathetic nerves to the heart, Increased plasma epinephrine
Which statements are true regarding the isovolumetric contraction phase of the cardiac cycle?
Pressure in the ventricles is increasing but is not sufficient to open the semilunar valves, The ventricles contain the end-diastolic volume of blood, All the valves are close
Which two of the following are mechanisms by which Ca2+ is removed from the cytosol of myocardial cells at the end of contraction?
Primary active transport by Ca2+ -ATPase pumps, Secondary active transport by Na+/Ca2+ countertransporters
Which of the following will result in an increase in a person's maximal oxygen consumption?
Regular endurance exercise training
Plasma proteins _______ pass readily through capillary walls; their influence on bulk flow is referred to as ________ osmotic pressure.
cannot and colloid
Exchange of nutrients, metabolic end products and cell secretions between the blood stream and interstitial fluid occurs in the systemic blood vessel type called _________.
capillaries
Activation of the parasympathetic branch of the autonomic nervous system _________ heart rate by increasing the permeability of SA node cells to _________.
decreases and K+
Activation of the parasympathetic branch of the autonomic nervous system _______.
decreases the heart rate
When arteriolar smooth muscle relaxes, the change in arteriole diameter that occurs is called _________.
dilation
The plateau phase of a myocardial action potential ________.
is sustained by diffusion of both Ca2+ and K+
Mechanisms that regulate smooth muscle contraction (independently of nerves or hormones) by which organs and tissues after their own arteriolar resistances and blood flow are referred to as _________.
local controls
Blood flow through a vessel is inversely proportional to the ________.
resistance
If you know the pressure difference between two points of a blood vessel without branches and the amount of blood flowing through it, you can calculate that blood vessel's ________.
resistance to blood flow
Pulse pressure is the difference between the ________ pressure and the ______ pressure.
systolic and diastolic
A heart murmur may be caused by _________.
septal defects, leaky valves, stenosis
The main cardiovascular variable that is regulated by homeostatic negative feedback control is ________,
systemic mean arterial pressure
