Topic 3 Part B

Question 0

If the SA node is non-functional, which of the following is most likely to occur?
A) the heart will go into asystole ( stop)
B) tachycardia will develop
C) another portion of the heart will become the pacemaker
D) the heart will go into fibrillation
E) the heart will be desensitized

Answer 0

A) the heart will go into asystole ( stop)
B) tachycardia will develop
C) another portion of the heart will become the pacemaker*
D) the heart will go into fibrillation
E) the heart will be desensitized

Question 1

Which of the following layers forms the bulk of the heart wall?
a) epicardium 
B) pericardium 
C) endocardium
D) myocardium 
E) visceral pericardium

Answer 1

a) epicardium 
B) pericardium 
C) endocardium
D) myocardium *
E) visceral pericardium

Question 2

Which of the following phrases would apply to cardiac muscle cells.
a) are organised in parallel columns or bundles
b) contain actin but no myosin
c) develop a significant oxygen debt during systole
d) are multinucleated like skeletal muscle cells
E) possess special cell to cell contacts called intercalated discs

Answer 2

a) are organised in parallel columns or bundles
b) contain actin but no myosin
c) develop a significant oxygen debt during systole
d) are multinucleated like skeletal muscle cells
e) possess special cell to cell contacts called intercalated discs*

Question 3

Cardiac muscle cells

a) have smooth ER but no T tubules
b) form the heart valves
c) are maintained by an extensive capillary network
d) develop a significant oxygen debt during systole
e) do not contain actin and myosin like skeletal muscle cells

Answer 3

a) have smooth ER but no T tubules
b) form the heart valves
c) are maintained by an extensive capillary network *
d) develop a significant oxygen debt during systole
e) do not contain actin and myosin like skeletal muscle cells

Question 4

The volume of blood pumped during each cardiac cycle is the

a) stroke volume
b) cardiac output
c) cardiac reserve
d) end-systolic volume
e) end-diastolic volume

Answer 4

a) stroke volume *
b) cardiac output
c) cardiac reserve
d) end-systolic volume
e) end-diastolic volume

Question 5

The pacemaker of the heart is the

a) right bundle branch
b) left bundle branch
c) AV node
d) SA node
e) PM node

Answer 5

a) right bundle branch
b) left bundle branch
c) AV node
d) SA node*
e) PM node

Question 6

Blood in the superior vena cava will enter the ____.

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Answer 6

a) aorta
b) right atrium *
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Question 7

The product of the stroke volume times the heart rate is known as the a) end-diastolic volume

b) end- systolic volume
c) cardiac output
d) cardiac reserve
e) venous return

Answer 7

a) end-diastolic volume
b) end- systolic volume
c) cardiac output *
d) cardiac reserve
e) venous return

Question 8

These vessels transport blood to the right and left lungs

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Answer 8

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries *
e) pulmonary veins

Question 9

The period of time in which the myocardium is insensitive to further stimulation is called the

a) absolute refractory period
b) hyperpolarization period
c) AV period
d) SA period
e) ectopic focus

Answer 9

a) absolute refractory period *
b) hyperpolarization period
c) AV period
d) SA period
e) ectopic focus

Question 10

The long refractory period observed in cardiac muscle

a) prolonged depolarization of the cardiac muscle
b) prevents tetanic contractions of the cardiac muscle
c) ensures that the heart has adequate time to contract
d) prevents the heart rate from slowing down
e) prevents an increase in heart rate

Answer 10

a) prolonged depolarization of the cardiac muscle
b) prevents tetanic contractions of the cardiac muscle *
c) ensures that the heart has adequate time to contract
d) prevents the heart rate from slowing down
e) prevents an increase in heart rate

Question 11

Blood vessels enter and exit from the _____ of the heart

a) apex
b) base
c) auricles
d) trigone
e) inferior aspect

Answer 11

a) apex
b) base *
c) auricles
d) trigone
e) inferior aspect

Question 12

Which of the following will increase the heart rate?

a) a rising in pH
b) an increase in the level of carbon dioxide in the blood
c) an increase in the level of blood oxygen
d) an increase in blood pressure
e) a decrease in the level of carbon dioxide in the blood

Answer 12

a) a rising in pH
b) an increase in the level of carbon dioxide in the blood *
c) an increase in the level of blood oxygen
d) an increase in blood pressure
e) a decrease in the level of carbon dioxide in the blood

Question 13

An incompetent mitral valve may cause blood to back up into the

a) aorta
b) left atrium
c) left ventricle
d) coronary circulation
e) right atrium

Answer 13

a) aorta
b) left atrium *
c) left ventricle
d) coronary circulation
e) right atrium

Question 14

This blood vessel carries blood from the left ventricle

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Answer 14

a) aorta *
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Question 15

The cardioregulatory center of the brain is located in the

a) hypothalamus
b) medulla oblongata
c) cerebellum
d) cerebrum
e) diencephalons

Answer 15

a) hypothalamus
b) medulla oblongata *
c) cerebellum
d) cerebrum
e) diencephalons

Question 16

Contraction of the papillary muscle would

a) eject blood from the ventricles
b) prevent the AV valves from protruding into the atria
c) close the semilunar valves
d) cause the atria to eject their contents into the ventricles
e) open the semilunar valve

Answer 16

a) eject blood from the ventricles
b) prevent the AV valves from protruding into the atria *
c) close the semilunar valves
d) cause the atria to eject their contents into the ventricles
e) open the semilunar valve

Question 17

Ventricular contraction begins at the

a) AV bundle
b) apex of the heart
c) base of the heart
d) superior portion of that intraventricular septum
e) top of the ventricles

Answer 17

a) AV bundle
b) apex of the heart *
c) base of the heart
d) superior portion of that intraventricular septum
e) top of the ventricles

Question 18

If the cardiac muscle cells are unable to repolarize, this would cause

a) cardiac output to increase
b) no harm. These cells can spontaneously depolarize anyway
c) the heart rate to decrease. it might cause cardiac arrest
d) an increased demand on mitochondria to produce more ATP
e) tachycardia

Answer 18

a) cardiac output to increase
b) no harm. These cells can spontaneously depolarize anyway
c) the heart rate to decrease. it might cause cardiac arrest *
d) an increased demand on mitochondria to produce more ATP
e) tachycardia

Question 19

Blood in the pulmonary vein returns to the

a) right atrium
b) left atrium
c) right ventricle
d) left ventricle
e) coronary sinus

Answer 19

a) right atrium
b) left atrium *
c) right ventricle
d) left ventricle
e) coronary sinus

Question 20

Blood returning to the heart from the systemic circuit first enters the

a) right atrium
b) right ventricle
c) left atrium
d) left ventricle
e) conus arteriosus

Answer 20

a) right atrium *
b) right ventricle
c) left atrium
d) left ventricle
e) conus arteriosus

Question 21

Chemoreceptors sensitive to blood carbon dioxide levels are primarily located in the

a) renal arteries
b) carotid arteries
c) right atrium
d) left ventricle
e) jugular veins

Answer 21

a) renal arteries
b) carotid arteries *
c) right atrium
d) left ventricle
e) jugular veins

Question 22

An incompetent pulmonary semilunar valve could result in less blood reaching the

a) lungs
b) heart muscle
c) right ventricle
d) aorta
e) right atrium

Answer 22

a) lungs *
b) heart muscle
c) right ventricle
d) aorta
e) right atrium

Question 23

The AV valve that is located on the same side of the heart as the origin of the aorta is the

a) bicuspid or mitral valve
b) tricuspid valve
c) aortic semilunar valve
d) pulmonary semilunar valve
e) coronary sinus valve

Answer 23

a) bicuspid or mitral valve *
b) tricuspid valve
c) aortic semilunar valve
d) pulmonary semilunar valve
e) coronary sinus valve

Question 24

The tricuspid valve is closed

a) during active feeling of the ventricles
b) when the mitral valve is open
c) while the atria are contracting
d) during ejection
e) during passive feeling of the ventricles

Answer 24

a) during active feeling of the ventricles
b) when the mitral valve is open
c) while the atria are contracting
d) during ejection *
e) during passive feeling of the ventricles

Question 25

The chamber of the heart that endures the highest pressure is the

a) right atrium
b) left atrium
c) right ventricle
d) left ventricle
e) coronary sinus

Answer 25

a) right atrium
b) left atrium
c) right ventricle
d) left ventricle *
e) coronary sinus

Question 26

The P wave of an ECG indicates

a) atrial depolarization
b) atrial repolarization
c) ventricular depolarization
d) ventricular repolarization
e) threshold

Answer 26

a) atrial depolarization *
b) atrial repolarization
c) ventricular depolarization
d) ventricular repolarization
e) threshold

Question 27

Which of the following is true

a) blood enters the right and left atria only during diastole
b) most ventricular filling occurs before the atria contract
c) during ventricular systole, the AV valves open
d) the semilunar valves remain closed throughout ventricular systole
e) most of end-diastolic volume comes from active filling

Answer 27

a) blood enters the right and left atria only during diastole
b) most ventricular filling occurs before the atria contract *
c) during ventricular systole, the AV valves open
d) the semilunar valves remain closed throughout ventricular systole
e) most of end-diastolic volume comes from active filling

Question 28

In a normal electrocardiogram, the

a) P wave results from repolarization of the atria
b) QRS complex results from ventricular depolarization
c) P wave occurs after the QRS complex but before the T-wave
d) T-wave represents depolarization of the atria
e) repolarization of the atria is clearly visible

Answer 28

a) P wave results from repolarization of the atria
b) QRS complex results from ventricular depolarization *
c) P wave occurs after the QRS complex but before the T-wave
d) T-wave represents depolarization of the atria
e) repolarization of the atria is clearly visible

Question 29

Which of the following factors would cause an increase in heart rate?

a) increased parasympathetic stimulation
b) stimulation of baroreceptors in the aorta
c) increased epinephrine (adrenalin) released from the adrenal medulla d) increased production of atrial natriuretic factor
e) vagal stimulation

Answer 29

a) increased parasympathetic stimulation
b) stimulation of baroreceptors in the aorta
c) increased epinephrine (adrenalin) released from the adrenal medulla*
d) increased production of atrial natriuretic factor
e) vagal stimulation

Question 30

Angina pectoris is chest pain caused by reduced

a) stimulation of the myocardium
b) blood supply to cardiac muscle
c) fluid in the pericardial sac
d) contractility of the heart
e) action potentials from SA node

Answer 30

a) stimulation of the myocardium
b) blood supply to cardiac muscle *
c) fluid in the pericardial sac
d) contractility of the heart
e) action potentials from SA node

Question 31

If the heart receives more sympathetic stimulation than parasympathetic stimulation, the heart will

a) increase its rate and force of contraction
b) contract with greater force but at a slower rate
c) decrease both its rate and force of contraction
d) contract with less force but at a faster rate
e) decrease rate, but increase force of contraction

Answer 31

a) increase its rate and force of contraction *
b) contract with greater force but at a slower rate
c) decrease both its rate and force of contraction
d) contract with less force but at a faster rate
e) decrease rate, but increase force of contraction

Question 32

Coronary-artery disease can diminish myocardial blood resulting in the death of myocardial cells. This condition is known as myocardial

a) attack
b) angina
c) necrosis
d) cirrhosis
e) infarction

Answer 32

a) attack
b) angina
c) necrosis
d) cirrhosis
e) infarction*

Question 33

The valve located between the right ventricle and the pulmonary trunk is the

a) aortic semilunar valve
b) pulmonary semilunar valve
c) tricuspid valve
d) mitral valve
e) bicuspid valve

Answer 33

a) aortic semilunar valve
b) pulmonary semilunar valve *
c) tricuspid valve
d) mitral valve
e) bicuspid valve

Question 34

Contraction of the ventricles is referred to as ventricular

a) systole
b) diastole
c) fibrillation
d) ischemia
e) depolarization

Answer 34

a) systole *
b) diastole
c) fibrillation
d) ischemia
e) depolarization

Question 35

Which of the following will depolarize immediately after the AV node depolarizes?

a) the AV bundle
b) Purkinje fibres
c) atrial myocardium
d) bundle branches in the ventricular septum
e) that SA node

Answer 35

a) the AV bundle *
b) Purkinje fibres
c) atrial myocardium
d) bundle branches in the ventricular septum
e) that SA node

Question 36

In the cardiac cycle

a) the right atrium and the right ventricle contract simultaneously
b) the two atria relax while the two ventricles contract
c) the left atrium contracts before the right atrium
d) all four chambers of the heart contract at the same time
e) all four chambers of the heart are in systole at the same time

Answer 36

a) the right atrium and the right ventricle contract simultaneously
b) the two atria relax while the two ventricles contract *
c) the left atrium contracts before the right atrium
d) all four chambers of the heart contract at the same time
e) all four chambers of the heart are in systole at the same time

Question 37

Which of the following sequences is correct

a) AV node, AV bundle, SA node, Purkinje fibers, bundle branches
b) Purkinje fibers, bundle branches, AV node, AV bundle, SA node
c) SA node,AV node, AV bundle, bundle branches, Purkinje fibers
d) SA node, AV bundle, AV node, bundle branches, Purkinje fibers
e) AV node, SA node, bundle branches, AV bundle, Purkinje fibers

Answer 37

a) AV node, AV bundle, SA node, Purkinje fibers, bundle branches
b) Purkinje fibers, bundle branches, AV node, AV bundle, SA node
c) SA node,AV node, AV bundle, bundle branches, Purkinje fibers*
d) SA node, AV bundle, AV node, bundle branches, Purkinje fibers
e) AV node, SA node, bundle branches, AV bundle, Purkinje fibers

Question 38

These vessels empty into the left atrium

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins

Answer 38

a) aorta
b) right atrium
c) pulmonary trunk
d) pulmonary arteries
e) pulmonary veins*

Question 39

Stimulation of the heart via the sympathetic nerves would

a) decrease heart rate
b) decreased stroke volume
c) increase the force of ventricular contraction
d) increase end-systolic volume
e) not affect the heart rate and force of contraction

Answer 39

a) decrease heart rate
b) decreased stroke volume
c) increase the force of ventricular contraction *
d) increase end-systolic volume
e) not affect the heart rate and force of contraction