Ch. 20
At a heart rate of 60 beats/minute, a cardiac cycle lasts
1 second
There are ________ pulmonary veins.
4
The following are structural components of the conducting system of the heart: 1. Purkinje fibers 2. AV bundle 3. AV node 4. SA node 5. bundle branches The sequence in which excitation would move through this system is
4, 3, 2, 5, 1
As the left ventricle contracts, it bulges into the ________.
right ventricular cavity
A fine tubular wire mesh called a ________ may be inserted into a coronary vessel, holding it open.
stent
Oxygen is removed from blood as it flows through the ________ circuit.
systemic
The ________ circuit carries blood from the aorta to the right ventricle.
systemic
A faster-than-normal heart rate is called ________.
tachycardia
As a result of the long refractory period in the cardiac action potential, cardiac muscle cannot exhibit
tetany
Blood is supplied to the myocardium by
the coronary arteries.
Intercalated discs serve to transfer ________ from cell to cell.
the force of contraction, ionic currents, action potentials
Which of the following is greater during left ventricular systole?
the peak pressure in the ventricle
Depolarization of the atria corresponds to the EKG's
P wave
The heart is roughly the size of
a man's clenched fist
________ is the symptom generally brought on by coronary ischemia.
angina pectoris
In a procedure known as balloon ________, an inflatable balloon at the end of a catheter is used to press plaque back against the vessel wall.
angioplasty
The left ventricle pumps blood to the
aorta
The inferior point of the heart is called the ________.
apex
Which of the following descriptions matches the term near the left fifth intercostal space?
apex
________ carry blood away from the heart.
arteries
In cardiac muscle
at least half of the calcium ion required for contraction comes from outside the cell.
The interventricular sulci and coronary sulcus contain
ateries, fat, veins
The heart has four chambers, two small thin-walled ________ and two large muscular ________.
atria, ventricles
The earlike extension of the atrium is the
auricle
The superior portion of the heart where major blood vessels enter and exit is the ________.
base
The bicuspid or mitral valve is located
between the left atrium and left ventricle.
The ________ valve prevents backward flow into the left atrium.
bicuspid
Rupture of the papillary muscles in the left ventricle may result in
bicuspid regurgitation, mitral regurgitation, bicuspid prolapse., mitral valve prolapse.
The function of the atrium is to
both collect blood and pump blood to the ventricle.
An increase in the rate of action potentials from baroreceptors will reflexly lead to
both decrease in heart rate and decrease in blood pressure.
In order to perform a CABG, a cardiac surgeon must
both open the pericardial sac and visualize the visceral pericardium.
Which of these comparisons between skeletal and heart muscle is false?
both rely entirely on oxidative metabolism for energy.
During the T wave of the electrocardiogram, the ventricles are
both repolarizing and relaxing.
The ________ deliver(s) blood to the myocardium.
both right coronary artery and left coronary artery
The wall of the left ventricle is thicker than the right because
both the left ventricle does more work than the right ventricle and the left ventricle produces a higher pressure than the right.
A slower-than-normal heart rate is called ________.
bradycardia
The long plateau phase of the cardiac muscle action potential is due to
calcium channels remaining open
Most of the middle layer in the heart wall is composed of
cardiac myocytes
The term used to describe fluid collecting in the pericardial cavity that restricts the movement of the heart is known as
cardiac tamponade
The cusps (leaflets) of atrioventricular valves attach directly to
chordae tendineae
As blood leaves the right ventricle it passes through the ________ and then into the pulmonary trunk.
conus arteriosus
The first blood vessels to branch from the aorta are the ________ arteries.
coronary
The term ________ refers to blockage in the coronary circulation.
coronary artery disease
The great and middle cardiac veins drain blood into the
coronary sinus
The right atrium receives blood from the
coronary sinus, superior vena cava, and inferior vena cava.
The ________ covers the outer surface of the heart.
epicardium
The visceral pericardium is the same as the
epicardium
The structure that permits blood flow from the right atrium to the left atrium in the fetal circulation is the
foramen ovale
The pulmonary veins carry blood to the
heart
The connective tissue fibers of the myocardium
help distribute the forces of contraction, add strength and prevent overexpansion of the heart, provide elasticity to help return the heart to its normal size, provide physical support for cardiac muscle
The atrioventricular valves permit blood flow
in one direction only
The ________ separates the two atria.
interatrial septum
The foramen ovale in the fetal heart is located in the
interatrial septum
The ________ is shared by the two ventricles.
interventricular septum
Blood returning to the heart from the pulmonary circuit first enters the
left atrium
Blood is supplied to the left atrium by the
left coronary artery
The circumflex branch and the anterior interventricular artery are branches of the
left coronary artery
The ________ is a remnant of an important fetal blood vessel that once linked the pulmonary and systemic circuits.
ligamentum arteriosum
The pulmonary arteries carry blood to the
lungs
The coronary sulcus is a groove that
marks the border between the atria and ventricles.
In the middle of the thoracic cavity is a region occupied by the heart, great vessels, thymus, esophagus, and trachea called the
mediastinum
The space between the pleural cavities is called the ________.
mediastinum
The muscle layer of the heart is the ________.
myocardium
When the semilunar valves close, the AV valves then
open
Excess fluid in the ________ causes cardiac tamponade.
pericardial cavity
The heart lies within the ________.
pericardial cavity
Contractions of the papillary muscles
prevent the atrioventricular valves from reversing into the atria.
Oxygen is added to blood as it flows through the ________ circuit.
pulmonary
The ________ circuit carries blood to and from the lungs.
pulmonary
Blood leaves the right ventricle by passing through the
pulmonary valve
Compared to the right ventricle, the left ventricle has all the following characteristics, except that it
pumps a greater volume
The right ventricle pumps blood to the
right and left lungs
Blood returning to the heart from the systemic circuit first enters the
right atrium
Coronary veins empty into the
right atrium
The marginal branch and posterior interventricular branch are branches of the
right coronary artery
The pulmonary semilunar valve prevents backward flow into the
right ventricle
The wall of the ________ rests on the diaphragm.
right ventricle
The following is a list of vessels and structures that are associated with the heart. 1. right atrium 2. left atrium 3. right ventricle 4. left ventricle 5. venae cavae 6. aorta 7. pulmonary trunk 8. pulmonary veins
5, 1, 3, 7, 8, 2, 4, 6
The heart pumps approximately ________ liters of blood each day.
8000
A procedure in which a length of the patient's vein or artery is used to create a detour around an obstruction in a coronary artery is called ________.
CABG
Cardiac muscle cells and skeletal muscle cells differ in a few ways. Which of the following is not one of them?
Cardiac muscle cells lack transverse tubules.
The normal pacemaker of the heart is located in the
SA node
What effect would compressing the inferior vena cava just below the diaphragm have on cardiac function?
Sympathetic stimulation of the heart would increase.
If there is a complete block between the SA node and the AV node, how would the ECG be affected?
The rate of P waves will be faster than the rate of QRS complexes.
When the left ventricle contracts, the diameter of the ventricular chamber
decreases
When the left ventricle contracts, the distance from the apex to the base
decreases
Artery is to ________ as vein is to ________.
efferent; afferent
The ________ lines the chambers of the heart, covers the heart valves, and is continuous with the endothelium.
endocardium
Tetanic muscle contractions don't occur in a normal cardiac muscle because
the refractory period lasts until the muscle relaxes.
If the connection between the SA node and AV node becomes blocked,
the ventricles will beat more slowly
Muscular ridges on the inner surface of the ventricles are called ________.
trabeculae carneae
Blood flowing into the heart from the venae cavae flows next through the ________ valve.
tricuspid
The long-term success rate of angioplasty greatly increases with the use of stents.
true
________ carry blood toward the heart.
veins
An equivalent term for epicardium is ________.
visceral pericardium