The blood vessels in the cardiovascular system are subdivided into the
pulmonary and systemic circuits
Blood is carried away from the heart by the
arteries
The left atrium receives blood from the pulmonary circuit and empties it into the
left ventricle
The double pump function of the heart includes the right side, which serves as the ________ circuit pump, while the left side serves as the ______ pump
pulmonary; systemic
The major difference between the left and right ventricles relative to their role in heart function is
the LV pumps blood through the high-resistance systemic circulation
The great cardiac vein drains blood from the heart muscle to the
right atrium
The visceral pericardium, or epicardium, covers the
outer surface of the heart
The valves of the heart are covered by a squamous epithelium, the
endocardium
The three distinct layers of the heart wall include the
epicardium, myocardium, endocardium
Atrioventricular valves prevent backflow of blood into the _______; semilunar valves prevent backflow into the _________
atria; ventricles
Blood flows from the left atrium into the left ventricle through the ________ valves
bicuspid, L. atrioventricular, mitral
When deoxygenated blood leaves the right ventricle through a semilunar valve, it is forced into the
pulmonary arteries
Blood from systemic circulation is returned to the right atrium by the
superior and inferior vena cava
Oxygenated blood from the systemic arteries flows into
peripheral tissue capillaries
The lung capillaries receive deoxygenated blood from the
pulmonary arteries
One of the important differences between skeletal muscle tissue and cardiac muscle tissue is that cardiac muscle tissue is
striated involuntary muscle
Cardiac muscle tissue
does not require nerve activity to stimlate a contraction
The primary differences that characterize cardiac muscle cells when comparing them to skeletal muscle fibers are
small size, a single centrally located nucleus, the presence of intercalated discs
Blood from coronary circulation is returned to the right atrium of the heart via
coronary sinus
The right coronary artery supplies blood to
the right atrium, portions of the conducting system of the heart, portions of the right and left ventricles
The correct sequential path of a normal action potential in the heart is
SA node -> AV node -> bundle of His -> bundle branches -> Purkinje fibers
If the papillary muscles fail to contract, the
AV valves will not close properly
The events between the start of one hearbeat and the start of the next is called the
cardiac cycle
The sinoatrial node acts as the pacemaker of the heart because these cells are
the ones that depolarize and reach threshold first
After the SA node is depolarized and the impulse spreads through the atria, there is a slight delay before the impulse spreads to the ventricles. The reason for this delay is to allow
the atria to finish contracting
If each heart muscle cell contracted at its own individual rate, the condition would resemble
fibrilation
The P wave of a normal electrocardiogram indicates
atrial depolarization
The QRS complex of the ECG appears as the
ventricles depolarize
ECGs are useful in detecting and diagnosing abonormal patterns of cardiac activity called
cardiac arrhythmias
An excessively large QRS complex often indicates that the
heart has become enlarged
The "lubb-dubb" sounds of the heart have practical clinical value because they provide information concerning
the action and efficiency of the AV and semilunar valves
When a chamber of the heart fills with blood and prepares for the start of the next beat the chamber is in
diastole
At the start of the atrial systole, the ventricles are filled to around
70% of capacity
The amount of blood ejected by the left ventricle per minute is the
cardiac output
The amount of blood pumped out of each ventricle during a single beat is the
stroke volume
Under normal circumstances, the factors responsible for making delicate adjustments to the heart rate as circulatory demands change are
autonomic activity and circulatory hormones
The cardiac centers in the medulla oblongata monitor baroreceptors and chemoreceptors innervated by the
glossopharyngeal N IX and vagus N X
The atrial reflex (Bainbridge reflex) involved adjustments in heart rate stimulated by an increase in
venous return
The difference between the end-distolic volume (EDV) and the end systolic volume (ESV) is the
stroke volume
Starling's Law of the Heart describes the relationship that states
increasing the EDV results in an increase in the stroke volume
Parasympathetic from the vagus nerve results in
a decrease in heart rate
Cutting the vagus nerve
increases the heart rate
If the heart rate is 78 bpm and the stroke volume is 80 ml per beat, the cardiac output will be
6,240ml/min
Assuming anatomic position, the best way to descibr the specific location of the heart in the body is
within the mediastinum of the thorax
The function of the chordae tendinae is to
anchor the AV valve flaps and prevent backflow of blood into the atria
Which one of the following would not show up on an electrocardiogram
murmors
During ventricular diastole, when the pressure in the left ventricle rises above that in the left atrium
the left AV valve closes
During ventricular systole, the blood volume in the atria is _______, and the volume in the ventricle is _______
increasing; decreasing
During most of the ventricular diastole
the pressure in the L. ventricle is slightly lower than the pressure in the L. atrium
When the pressure within the L. ventricle becomes greater than the pressure within the aorta
the aortic semilunar valve is forced open
The volume of blood in the L. ventricle is at its lowest when
the AV valve opens
The dicrotic wave indicates a brief rise in the aortic pressure. The rise in pressure is due to
the closure of the semilunar valve
During isovlumertric contraction, pressure is highest in the
aorta
Blood pressure in the large systemic arteries is greatest during
systolic ejection
Decreased parasympathetic (vagus) stimulation to the heart results in
speeding the heart rate
Serious arrhythmias that reduce the pumping efficiency of the heart may indicate
damage to the myocardium, injury to the SA and AV nodes, abnormalities in the ionic composition of the extracellular fluids
During exercise the most important mechanism to increase cardiac output is
increased sympathetic activity to the ventricles
The diastolic phase of the blood pressure indicates that
the ventricles are "resting
Which of the following does not control the movement of blood through the heart
size of the atria and ventricles
The ANS can make very delicate adjustments in cardiovascular function to meet demands of other systems through
dual innervation and adjustments in autonomic tone
Normally, the only electrical connection between the atria and the ventricles is the
bundle of His
If the SA node or internodal pathways are damaged, the
AV node assumes command
Tetanic contractions cannot occur in a normal cardiac muscle cell, regardless of the frequency or intensity of stimulation, because
summation is not possible