Deck 19: The Circulatory System: Heart

Question 1

Hypercapnia and acidosis have positive chronotropic effects.

Answer 1

True

Question 2

Parasympathetic stimulation reduces heart rate.

Answer 2

True

Question 3

Which of the following belong to the pulmonary circuit?

A) Aorta and venae cavae
B) Aorta and pulmonary veins
C) Pulmonary arteries and venae cavae
D) Venae cavae and pulmonary veins
E) Pulmonary arteries and pulmonary veins

Answer 3

E

Question 4

The systemic circuit contains oxygen-rich blood only.

Question 5

The fibrous skeleton of the heart serves as electrical insulation between the atria and the ventricles.

Question 6

Ventricular pressure increases the fastest during ventricular filling.

Question 7

Papillary muscles prevent the AV valves from prolapsing (bulging)excessively into the atria when the ventricles contract.

Question 8

The cardiac plexus and cardiac nerves dominate the innervation of the heart and contains both parasympathetic and sympathetic fibers.

Question 9

If the SA node is damaged,nodal rhythm is sufficient to sustain life.

Question 10

Endurance athletes commonly have a resting heart rate as low as 40 bpm,and a stroke volume as low as 50 mL/beat.

Question 11

The pulmonary circuit is supplied by both the right and the left sides of the heart.

Question 12

Repolarization of a ventricular cardiomyocyte takes longer than repolarization of a typical neuron.

Question 13

Exercise causes the ventricles to hypertrophy.

Question 14

Atrial hypertrophy would probably cause an enlarged P wave on an electrocardiogram.

Question 15

Cardiac muscle can only use glucose as a source of organic fuel.

Question 16

The ventricles are almost empty at the end of ventricular diastole.

Question 17

Which of the following carry oxygen-poor blood?

A) Pulmonary veins and vena cavae
B) Aorta and pulmonary veins
C) Aorta and vena cavae
D) Venae cavae and pulmonary arteries
E) Pulmonary veins and pulmonary arteries

Question 18

Blood in the heart chambers provides most of the myocardium's oxygen and nutrient needs.

Question 19

Which of the following is the most superficial layer enclosing the heart?

A) Parietal pericardium
B) Visceral pericardium
C) Endocardium
D) Epicardium
E) Myocardium

Question 20

Desmosomes form channels that allow each cardiomyocyte to electrically stimulate its neighbors.

Question 21

Which of the following is a feature shared by cardiac muscle and skeletal muscle?

A) Muscle fiber striations
B) Dependence upon nervous stimulation
C) Communication via electrical (gap)junctions
D) Intercalated discs
E) Autorhythmicity

Question 22

Which of the following directly stems from the ascending aorta before it branches into the circumflex branch and anterior interventricular branch?

A) Right coronary artery
B) Great cardiac vein
C) Right coronary vein
D) Left coronary artery
E) Left coronary vein

Question 23

Obstruction of the ___________ will cause a more severe myocardial infarction (MI)than the obstruction of any of the others.

A) left marginal vein
B) left coronary artery (LCA)
C) posterior interventricular vein
D) anterior interventricular branch
E) circumflex branch

Question 24

The apex of the heart is found __________ of the midline of the body.

A) to the right
B) to the left
C) in the center

Question 25

The chordae tendinae of the AV valves are anchored to the __________ of the ventricles.

A) papillary muscles
B) pectinate muscles
C) trabeculae carnae
D) interventricular septum
E) interatrial septum

Question 26

The shallow depression seen on the external surface of the heart between the left and right ventricles is called the __________.

A) coronary sinus
B) interventricular sulcus
C) interventricular septum
D) coronary sulcus
E) left atrium

Question 27

Pericardial fluid is found between the __________ and the __________.

A) visceral pericardium;myocardium
B) visceral pericardium;epicardium
C) parietal;visceral membranes
D) myocardium;endocardium
E) epicardium;myocardium

Question 28

Which of the following is not part of the cardiac conduction system?

A) Sinoatrial (SA)node
B) Tendinous cords
C) Atrioventricular (AV)node
D) Atrioventricular (AV)bundle (bundle of His)
E) Subendothelial conducting network

Question 29

The heart is located in the space called the __________.

A) pericardial cavity
B) mediastinum
C) abdominal cavity
D) pleural cavity
E) myocardium

Question 30

Oxygen-poor blood passes through the _________.

A) right AV (tricuspid)and pulmonary valves
B) right AV (tricuspid)valve only
C) left AV (mitral)and aortic valves
D) left AV (mitral)valve only
E) pulmonary and aortic valves

Question 31

Opening and closing of the heart valves is caused by _________.

A) breathing
B) gravity
C) valves contracting and relaxing
D) osmotic gradients
E) pressure gradients

Question 32

The __________ is the pacemaker that initiates each heart beat.

A) sympathetic division of the nervous system
B) autonomic nervous system
C) sinoatrial (SA)node
D) atrioventricular (AV)node
E) cardiac conduction system

Question 33

The __________ valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs.

A) right atrioventricular
B) left atrioventricular
C) aortic
D) pulmonary
E) mitral

Question 34

The __________ carry blood toward the lungs.

A) pulmonary arteries and veins
B) pulmonary trunk and arteries
C) pulmonary trunk and veins
D) superior and inferior venae cavae
E) aorta and pulmonary arteries

Question 35

Which of the following blood vessels receives blood directly from the right ventricle?

A) Pulmonary trunk
B) Ascending aorta
C) Superior vena cava
D) Inferior vena cava
E) Right pulmonary vein

Question 36

The __________ are the superior chambers of the heart and the _________ are the inferior chambers of the heart.

A) visceral percardia;parietal pericardia
B) ventricles;atria
C) atria;ventricles
D) left ventricles;right ventricles
E) left atria;right atria

Question 37

The __________ performs the work of the heart.

A) fibrous skeleton
B) pericardial cavity
C) endocardium
D) myocardium
E) epicardium

Question 38

The area where the major vessels lead to and from the heart's chambers is called the __________ of the heart.The pointy,inferior portion is called the ___________.

A) apex;base
B) atrium;ventricle
C) ventricle;atrium
D) base;apex
E) endocardium;epicardium

Question 39

The right atrioventricular valve (tricuspid)regulates the opening between the _________ and the _________.

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

Question 40

After entering the right atrium,the furthest a red blood cell can travel is the _________.

A) right ventricle
B) pulmonary trunk
C) superior vena cava
D) ascending aorta
E) left atrium

Question 41

Atrial depolarization causes the _________.

A) P wave
B) QRS complex
C) T wave
D) first heart sound
E) quiescent period

Question 42

The plateau in the action potential of cardiac muscle results from the action of __________.

A) Na⁺ inflow
B) K⁺ inflow
C) K⁺ outflow
D) fast Ca²⁺ channels
E) slow Ca²⁺ channels

Question 43

Cells of the sinoatrial node __________ during the pacemaker potential.

A) depolarize fast
B) depolarize slow
C) repolarize slow
D) repolarize fast
E) depolarize slow and repolarize fast

Question 44

An extended period of time between the P wave and the QRS complex may indicate which of the following?

A) The signal is taking too long to get to the AV node.
B) The signal is traveling too quickly to the AV node.
C) Ventricular contraction is taking longer than usual.
D) Ventricular contraction is faster than usual.
E) The atria are not contracting.

Question 45

When the left ventricle contracts,the __________ valve closes and the __________ valve is pushed open.

A) mitral;pulmonary
B) right AV;pulmonary
C) right AV;aortic
D) mitral;aortic
E) aortic;pulmonary

Question 46

The long absolute refractory period of cardiomyocytes _________.

A) ensures a short twitch
B) prevents tetanus
C) makes the heart prone to arrhythmias
D) prevents the occurrence of ectopic focuses
E) causes the pacemaker potential

Question 47

Which is the correct path of an electrical excitation from the pacemaker to a cardiomyocyte in the left ventricle (LV)?

A) Sinoatrial (SA)node → atrioventricular (AV)bundle → atrioventricular (AV)node → Subendothelial conducting network → cardiomyocyte in LV
B) Atrioventricular (AV)node → subendothelial conducting network → atrioventricular (AV)bundle → sinoatrial (SA)node → cardiomyocyte in LV
C) Atrioventricular (AV)node → sinoatrial (SA)node → atrioventricular (AV)bundle → Subendothelial conducting network → cardiomyocyte in LV
D) Sinoatrial (SA)node → atrioventricular (AV)node → atrioventricular (AV)bundle → Subendothelial conducting network → cardiomyocyte in LV
E) Sinoatrial (SA)node → atrioventricular (AV)node → Subendothelial conducting network → atrioventricular (AV)bundle → cardiomyocyte in LV

Question 48

Mitral valve prolapse causes blood to leak back into the __________ when the ventricles contract.

A) left atrium
B) right atrium
C) aorta
D) pulmonary trunk
E) pulmonary arteries

Question 49

During isovolumetric contraction,the pressure in the ventricles __________.

A) falls rapidly
B) rises rapidly
C) remains constant
D) rises and then falls
E) falls and then rises

Question 50

The pacemaker potential is a result of _________.

A) Na⁺ inflow
B) Na⁺ outflow
C) K⁺ inflow
D) K⁺ outflow
E) Ca²⁺ inflow

Question 51

When sodium channels are fully open,the membrane of the ventricular cardiomyocyte _________.

A) sharply hyperpolarizes
B) sharply repolarizes
C) sharply depolarizes
D) plateaus
E) has no reponse

Question 52

The __________ provides most of the Ca²⁺ needed for myocardial contraction.

A) extracellular fluid
B) mitochondria
C) sarcoplasmic reticulum
D) Golgi apparatus
E) cytoskeleton

Question 53

If the sinoatrial (SA)node is damaged,the heart will likely beat at __________ bpm.

A) 0 to 10
B) 10 to 20
C) 20 to 40
D) 40 to 50
E) 70 to 80

Question 54

Mitral valve prolapse (MVP)generates a murmur associated with the __________ heart sound that occurs when the __________.

A) lubb (S1);atria contract
B) dupp (S2);atria relax
C) lubb (S1);ventricles contract
D) dupp (S2);ventricles relax
E) lubb (S1);ventricles relax

Question 55

The long plateau in the action potential observed in cardiomyocytes is probably related with __________ staying longer in the cytosol.

A) Na⁺
B) K⁺
C) Ca²⁺
D) Cl^-
E) Na⁺,K⁺,and Ca²⁺

Question 56

Isovolumetric contraction occurs during the __________ of the electrocardiogram.

A) P wave
B) P-Q segment
C) R wave
D) S-T segment
E) T wave

Question 57

In a normal ECG,the deflection that is generated by ventricular repolarization is called the __________.

A) R wave
B) QRS wave
C) P wave
D) S wave
E) T wave

Question 58

Which of the following is not a feature of cardiac muscle?

A) They depend almost exclusively on aerobic respiration.
B) They are rich in glycogen.
C) They have larger than average mitochondria.
D) They are very rich in myoglobin.
E) They have about the same endurance as skeletal muscle fibers.

Question 59

Any abnormal cardiac rhythm is called a(n)__________.

A) ectopic focus
B) sinus rhythm
C) nodal rhythm
D) heart block
E) arrhythmia

Question 60

Atrial systole begins __________.

A) immediately before the P wave
B) immediately after the P wave
C) during the Q wave
D) during the S-T segment
E) immediately after the T wave

Question 61

Which is the correct sequence of events of the cardiac cycle?

A) Ventricular filling → isovolumetric contraction → isovolumetric relaxation → ventricular ejection
B) Ventricular filling → isovolumetric relaxation → isovolumetric contraction → ventricular ejection
C) Ventricular filling → ventricular ejection → isovolumetric contraction → isovolumetric relaxation
D) Ventricular filling → isovolumetric relaxation → ventricular ejection → isovolumetric contraction
E) Ventricular filling → isovolumetric contraction → ventricular ejection → isovolumetric relaxation

Question 62

When the ventricles relax,the __________ valve prevents backflow of blood into the left ventricle.

A) aortic
B) pulmonary
C) mitral
D) left AV
E) right AV

Question 63

The volume of blood ejected by each ventricle in one minute is called the __________.

A) cardiac reserve
B) preload
C) afterload
D) stroke volume
E) cardiac output

Question 64

Cardioinhibitory centers in the __________ receive input from __________.

A) cortex;proprioceptors in the muscles
B) thalamus;chemoreceptors in the medulla oblongata
C) hypothalamus;proprioceptors in the joints
D) medulla oblongata;chemoreceptors in the aortic arch
E) pons;baroreceptors in the internal carotid

Question 65

Electrical signals pass between cardiomyocytes through the _____.

A) gap junctions
B) desmosomes
C) tight junctions
D) hemidesmosomes

Question 66

Most of the ventricle filling occurs __________.

A) during atrial systole
B) when the AV valve is closed
C) during ventricular systole
D) during atrial diastole
E) during isovolumetric contraction

Question 67

Blood pressure is usually measured in millimeters of mercury (mmHg)but could be measured with any liquid,such as water (mm H₂0).

Question 68

The Frank-Starling law of the heart states that stroke volume is proportional to __________.

A) the end-systolic volume
B) the end-diastolic volume
C) the afterload
D) the heart rate
E) contractility

Question 69

The ventricles are the thicker more powerful chambers of the heart.They pump blood to the lungs and body.

Question 70

Assume that the left ventricle of a child's heart has an EDV=90mL,and ESV=60mL,and a cardiac output of 2,400 mL/min.His SV is __________ mL/beat and his HR is __________ bpm.

A) 30;80
B) 40;60
C) 80;30
D) 150;16
E) 16;150

Question 71

Mercury is used to measure blood pressure because it is __________ compared to other liquids.

A) more dense
B) less dense
C) darker in color
D) lighter in color
E) warmer

Question 72

When the aortic semilunar valve closes and blood bounces off of it,it produces the __________ heart sound that is ultimately related to when the __________.

A) lubb (S1);atria contract
B) dupp (S2);atria relax
C) lubb (S1);ventricles contract
D) dupp (S2);ventricles relax
E) lubb (S1);ventricles relax

Question 73

Stroke volume is increased by __________.

A) high arterial blood pressure
B) negative inotropic agents
C) increased venous return
D) increased afterload
E) dehydration

Question 74

Congestive heart failure (CHF)of the right ventricle __________.

A) can cause pulmonary edema
B) can cause systemic edema
C) increases the ejection fraction of the right ventricle
D) reduces the ejection fraction of the left ventricle
E) increases cardiac output in both ventricles

Question 75

The amount of blood pumped through the pulmonary circuit is less than the amount pumped through the systemic circuit.