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