Cardiac output is __________.

A)the amount of blood filling each ventricle at the end of diastole
B)the amount of blood pumped out of the heart during every ventricular contraction
C)the number of impulses fired by the SA node in one minute
D)the amount of blood pumped out of each ventricle in one minute
E)the number of times the heart beats in one minute

D)the amount of blood pumped out of each ventricle in one minute

Choose the correct sequence of current flow through the heart wall.

A)AV node, Purkinje fibers, AV node, AV bundle, right and left bundle branches
B)SA node, AV node, AV bundle, right and left bundle branches, Purkinje fibers
C)AV node, SA node, Purkinje fibers, AV bundle, right and left bundle branches
D)SA node, Purkinje fibers, AV node, AV bundle, right and left bundle branches
E)Purkinje fibers, AV node, AV bundle, right and left bundle branches, SA node

B)SA node, AV node, AV bundle, right and left bundle branches, Purkinje fibers

During pulmonary circulation, blood leaves the __________.

A)right atrium and goes directly to the left ventricle
B)right ventricle and goes directly to the aorta
C)right ventricle and moves to the lungs
D)right atrium and goes directly to the lungs
E)left ventricle and moves to the lungs

C)right ventricle and moves to the lungs

During systemic circulation, blood leaves the __________.

A)right ventricle and moves to the lungs
B)right ventricle and goes directly to the aorta
C)right atrium and goes directly to the lungs
D)lungs and moves to the left atrium
E)left ventricle and goes directly to the aorta

B)right ventricle and goes directly to the aorta

Identify the correct sequence of blood flow through the chambers of the heart.

A)left ventricle, left atrium, lungs, right ventricle, right atrium
B)right ventricle, left ventricle, left atrium, lungs, right atrium
C)left atrium, left ventricle, right ventricle, right atrium, lungs
D)right atrium, right ventricle, lungs, left atrium, left ventricle
E)lungs, right ventricle, left ventricle, right atrium, left atrium

D)right atrium, right ventricle, lungs, left atrium, left ventricle

The absolute refractory period refers to the time during which __________.

A)a skeletal muscle cannot respond to any stimulus and lasts about 250 milliseconds
B)the muscle cell is ready to respond to a threshold stimulus
C)the muscle cell is not in a position to respond to a stimulus of any strength
D)the muscle cell is ready to respond to any stimulus
E)a cardiac muscle cannot respond to any stimulus and lasts only 1 to 2 milliseconds

C)the muscle cell is not in a position to respond to a stimulus of any strength

The cardiac cycle includes all of the following events EXCEPT __________.

A)the movement of impulse from the SA node to all regions of the heart wall
B)the closing and opening of the heart valves during each heartbeat
C)the changes in pressure gradients in all chambers of the heart
D)the number of times the heart beats in one minute
E)the changes in blood volume in all chambers of the heart

D)the number of times the heart beats in one minute

The coronary arteries arise from the __________.

A)right atrium
B)Pulmanary trunk
C)superior vena cava
D)aorta
E)inferior vena cava

D)aorta

The endocardium is composed of __________.

A)simple columnar epithelium
B)cardiac muscle cells
C)simple squamous epithelium
E)simple cuboidal epithelium
F)stratified squamous epithelium

C)simple squamous epithelium

The inferior vena cava brings blood from the lower regions of the body and empties into the __________.

A)right ventricle
B)left ventricle
C)left atrium
D)right atrium
E)aorta

D)right atrium

The inner lining of the fibrous pericardium is formed by the __________.

A)endocardium
B)myocardium
C)epicardium
D)parietal layer of serous pericardium
E)pericardial cavity
F)diaphragm

D)parietal layer of serous pericardium

The interventricular septum forms a dividing wall between the __________.

A)left atrium and left ventricle
B)right ventricle and left atrium
C)left atrium and right atrium
D)right atrium and right ventricle
E)left and right ventricles

E)left and right ventricles

The normal pacemaker of the heart is the __________.

A)the bundle branches
B)AV node
C)SA node
D)Purkinje fibers
E)AV bundle

C)SA node

The tricuspid valve is located between the __________.

A)right and left atria
B)left atrium and left ventricle
C)right and left ventricles
D)right ventricle and the aorta
E)right atrium and right ventricle

E)right atrium and right ventricle

When the mitral valve closes, it prevents the backflow of blood from the __________.

A)left ventricle into the aorta
B)left ventricle into the left atrium
C)right ventricle into the pulmonary trunk
D)left atrium into the left ventricle
E)right atrium into the right ventricle

B)left ventricle into the left atrium

Which is the correct sequence of layers in the heart wall, starting with the outer layer?

A)endocardium, epicardium, myocardium
B)endocardium, smooth muscle, epicardium
C)epicardium, myocardium, endocardium
D)myocardium, pericardium, endocardium
E)parietal pericardium, myocardium, endocardium

C)epicardium, myocardium, endocardium

Which of the following statements is NOT true about the shape, position, and location of the heart?

A)The heart is shaped like a cone with the base facing the right shoulder.
B)The heart is located between the two lungs within the mediastinum.
C)Approximately two-thirds of the heart is found to the left of the midline.
D)The heart is enclosed in a double-layered sac called the pleural membrane.

D)The heart is enclosed in a double-layered sac called the pleural membrane.

The vessels that carry oxygen to the myocardium are called __________.

A)coronary veins
B)pulmonary veins
C)coronary arteries
D)pulmonary arteries
E)aortic arteries

C)coronary arteries

The cells of the myocardium behave as a single, coordinated unit called a __________.

A)cardiac cycle
B)pacemaker
C)sarcomere
D)contractile unit
E)functional syncytium

E)functional syncytium

The ability of some cardiac muscle cells to initiate their own depolarization and cause depolarization of the rest of the heart is called __________.

A)automaticity
B)fibrillation
C)an action potential
E)a functional syncytium
F)the absolute refractory period

A)automaticity

Guided by powerful signaling molecules, the human heart develops from __________.

A)ectoderm
B)mesoderm
C)cardioderm
D)endoderm

B)mesoderm

Which of the following structures lies on the outside surface of the heart and is an integral part of the cardiac wall?

A)the fibrous pericardium
B)the epicardium
C)the pericardial sac
D)the parietal layer of serous pericardium

B)the epicardium

The trabeculae carneae are located in the __________.

A)atrium
B)endocardium
C)ventricles
D)epicardium

C)ventricles

What part of the heart is considered the systemic circuit pump?

A)the right ventricle
B)the left atrium
C)the left ventricle
D)the right atrium

C)the left ventricle

The __________ are attached to the AV valve flaps.

A)trabeculae carneae
B)pectinate muscles
C)chordae tendineae
D)papillary muscles

C)chordae tendineae

Which of the following valves is most often faulty in the heart?

A)the pulmonary semilunar valve
B)the tricuspid valve
C)the mitral, or bicuspid, valve
D)the aortic semilunar valve

C)the mitral, or bicuspid, valve

Which of the following factors gives the myocardium its high resistance to fatigue?

A)gap junctions
B)the coronary circulation
C)the presence of intercalated discs
D)a very large number of mitochondria in the cytoplasm

D)a very large number of mitochondria in the cytoplasm

The __________ nerve carries parasympathetic fibers to the sinoatrial (SA) node.

A)hypoglossal
B)vagus
C)facial
D)accessory

B)vagus

An enlarged R wave on an ECG would indicate __________.

A)cardiac ischemia
B)repolarization abnormalities
C)a myocardial infarction
D)an enlarged ventricle

D)an enlarged ventricle

A doctor puts his stethoscope on a patient's chest over the location of the heart and hears a swishing sound. Which of the following conditions is the best diagnosis for the patient's condition?

A)incompetent cardiac valve
B)myocardial infarction
C)angina pectoris
D)cardiac tamponade

A)incompetent cardiac valve

Which of the following is NOT a role of the pericardium?

A)It protects the heart.
B)It anchors the heart to surrounding structures.
C)It prevents the heart from overfilling with blood.
D)It facilitates heart contraction.

D)It facilitates heart contraction.

The lining of the heart chambers is called the __________.

A)myocardium
B)epicardium
C)endocardium
D)pericardium

C)endocardium

The superior chambers of the heart are called the __________.

A)atria
B)ventricles
C)cavea
D)coronary chambers

A)atria

Freshly oxygenated blood is delivered to the __________ and then it passes into the __________ to be pumped to the entire body.

A)right ventricle; right atrium
B)right atrium; right ventricle
C)left ventricle; left atrium
D)left atrium; left ventricle

D)left atrium; left ventricle

Into which chamber of the heart do the pulmonary veins deliver blood?

A)right ventricle
B)right atrium
C)left ventricle
D)left atrium

D)left atrium

right marginal artery

A)supplies blood to the left atrium and posterior walls of the left ventricle
B)supplies blood to the interventricular septum and anterior walls of both ventricles
C)supplies blood to the lateral right side of the myocardium
D)runs to the apex of the heart

C)supplies blood to the lateral right side of the myocardium

posterior interventricular artery

A)supplies blood to the left atrium and posterior walls of the left ventricle
B)supplies blood to the interventricular septum and anterior walls of both ventricles
C)supplies blood to the lateral right side of the myocardium
D)runs to the apex of the heart

D)runs to the apex of the heart

anterior interventricular artery

A)supplies blood to the left atrium and posterior walls of the left ventricle
B)supplies blood to the interventricular septum and anterior walls of both ventricles
C)supplies blood to the lateral right side of the myocardium
D)runs to the apex of the heart

B)supplies blood to the interventricular septum and anterior walls of both ventricles

circumflex artery

A)supplies blood to the left atrium and posterior walls of the left ventricle
B)supplies blood to the interventricular septum and anterior walls of both ventricles
C)supplies blood to the lateral right side of the myocardium
D)runs to the apex of the heart

A)supplies blood to the left atrium and posterior walls of the left ventricle

The most muscular chamber of the heart is the __________.

A)left atrium
B)right atrium
C)right ventricle
D)left ventricle

D)left ventricle

tricuspid valve

A)prevents backflow of blood into the left ventricle
B)valve between the right atrium and right ventricle
C)prevents backflow of blood into the right ventricle
D)valve between the left atrium and left ventricle

B)valve between the right atrium and right ventricle

mitral valve

A)prevents backflow of blood into the left ventricle
B)valve between the right atrium and right ventricle
C)prevents backflow of blood into the right ventricle
D)valve between the left atrium and left ventricle

D)valve between the left atrium and left ventricle

aortic semilunar valve

A)prevents backflow of blood into the left ventricle
B)valve between the right atrium and right ventricle
C)prevents backflow of blood into the right ventricle
D)valve between the left atrium and left ventricle

A)prevents backflow of blood into the left ventricle

pulmonary semilunar valve

A)prevents backflow of blood into the left ventricle
B)valve between the right atrium and right ventricle
C)prevents backflow of blood into the right ventricle
D)valve between the left atrium and left ventricle

C)prevents backflow of blood into the right ventricle

Which of the following is a difference between cardiac muscle and skeletal muscle?

A)Unlike skeletal muscle cells, cardiac muscle cells can be autorhythmic.
B)Unlike skeletal muscle, cardiac muscle is not striated.
C)Unlike skeletal muscle cells, cardiac muscle cells do not rely on an influx of calcium ions for depolarization.
D)Unlike skeletal muscle, cardiac muscle does not use a sliding filament mechanism for contraction.

A)Unlike skeletal muscle cells, cardiac muscle cells can be autorhythmic

The role of the atrioventricular node (AV node) is to __________.

A)slow down impulses so that the atria can contract to fill the adjacent ventricles with blood
B)initiate a sinus rhythm
C)conduct impulses to the sinoatrial node (SA node)
D)initiate ventricular depolarization

B)initiate a sinus rhythm

Which is correctly paired?

A)heart block: uncoordinated atrial and ventricular contraction
B)arrhythmia: AV node failure
C)fibrillation: premature contraction
D)ectopic focus: an abnormal pacemaker

D)ectopic focus: an abnormal pacemaker

The P wave of an electrocardiogram represents __________.

A)atrial repolarization
B)ventricular repolarization
C)atrial depolarization
D)ventricular depolarization

C)atrial depolarization

The second heart sound (the 'dup' of 'lub-dup') is caused by the __________.

A)opening of the semilunar valves
B)closure of the atrioventricular valves
C)opening of the atrioventricular valves
D)closure of the semilunar valves

D)closure of the semilunar valves

cardiac cycle

A)contraction
B)relaxation
C)the volume of blood pumped by one ventricle with each heartbeat
D)the amount of blood pumped by each ventricle in one minute
E)the events associated with blood flow through the heart during one complete heartbeat

E)the events associated with blood flow through the heart during one complete heartbeat

systole

A)contraction
B)relaxation
C)the volume of blood pumped by one ventricle with each heartbeat
D)the amount of blood pumped by each ventricle in one minute
E)the events associated with blood flow through the heart during one complete heartbeat

A)contraction

diastole

A)contraction
B)relaxation
C)the volume of blood pumped by one ventricle with each heartbeat
D)the amount of blood pumped by each ventricle in one minute
E)the events associated with blood flow through the heart during one complete heartbeat

B)relaxation

stroke volume

A)contraction
B)relaxation
C)the volume of blood pumped by one ventricle with each heartbeat
D)the amount of blood pumped by each ventricle in one minute
E)the events associated with blood flow through the heart during one complete heartbeat

C)the volume of blood pumped by one ventricle with each heartbeat

cardiac output

A)contraction
B)relaxation
C)the volume of blood pumped by one ventricle with each heartbeat
D)the amount of blood pumped by each ventricle in one minute
E)the events associated with blood flow through the heart during one complete heartbeat

D)the amount of blood pumped by each ventricle in one minute

Which of the following would lead to a decrease in heart rate?

A)norepinephrine
B)exercise
C)parasympathetic stimulation
D)sharply decreased blood volume

C)parasympathetic stimulation

True or False
In the fetus, blood from the left and right sides of the heart normally mix.

True