Deck 9: The Cardiovascular System

Question 1

What are the first arteries to branch off the ascending aorta?

A)brachiocephalic
B)carotid
C)coronary
D)subclavian

Answer 1

C

Question 2

Narrowing of the mitral valve (mitral stenosis) results in which of the following?

A)increased afterload on left ventricle
B)increased preload on right ventricle
C)increased pulmonary congestion
D)systemic hypertension

Answer 2

C

Question 3

The mitral (bicuspid) valve does which of the following?

A)prevents atrial backflow during ventricular contraction
B)separates the right atrium and the left atrium
C)separates the right atrium and the right ventricle
D)separates the right ventricle and the pulmonary artery

Answer 3

A

Question 4

What in essence is Frank-Starling's law of the heart?

A)the greater the stretch, the stronger the contraction
B)the less the afterload, the greater the ejection fraction
C)describes the inverse relationship between diameter and resistance to flow
D)curves show the hysteresis variations between systole and diastole

Question 5

Which of the following mechanisms facilitates venous return to the heart?
I)sodium/potassium pump
II)sympathetic venomotor tone
III)cardiac suction
IV)skeletal muscle contraction

A)I and II
B)II, III, and IV
C)I, II, III, and IV
D)III and IV

Question 6

What makes it impossible for myocardium to go into tetany?

A)absolute refractory period
B)automaticity
C)cardiac myofibrils
D)intercalated discs

Question 7

Which of the following represent the normal order of structures encountered by blood flowing from the vena cava to the aorta?

A)RA, tricuspid valve, RV, pulmonary valve, pulmonary veins, pulmonary artery, LA, mitral valve, LV, aortic valve
B)RA, tricuspid valve, RV, aortic valve, pulmonary artery, pulmonary veins, LA, mitral valve, LV, pulmonary valve
C)RA, tricuspid valve, LV, pulmonary valve, pulmonary artery, pulmonary veins, LA, mitral valve, RV, aortic valve
D)RA, tricuspid valve, RV, pulmonary valve, pulmonary artery, pulmonary veins, LA, mitral valve, LV, aortic valve

Question 8

What is the loose membranous sac that encloses the heart?

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

Question 9

The branches of the left coronary artery DO NOT supply which area of the heart?

A)majority of the interventricular septum
B)majority of the left ventricle
C)majority of the left atrium
D)sinus node

Question 10

Before draining into the right atrium, where do the large veins of the coronary circulation gather together?

A)coronary sinus
B)left posterior coronary vein
C)right coronary sulcus
D)thebesian veins

Question 11

Why are the vessels of the venous system, particularly the small venules and veins, termed capacitance vessels?

A)They transmit and maintain the head of perfusion pressure.
B)They can alter their capacity to maintain adequate perfusion.
C)They determine the afterload on the left ventricle.
D)They maintain a constant environment for the body's cells.

Question 12

What are the major branches of the left coronary artery?
I)anterior descending
II)circumflex
III)coronary sinus
IV)posterior descending

A)I, II, and III
B)II and IV
C)I and II
D)II and III

Question 13

Mixing of venous blood with arterial blood (a right-to-left shunt) occurs normally because of which of the following?
I)congenital cardiac defects
II)bronchial venous drainage
III)thebesian venous drainage in the heart

A)I, II, and III
B)II and III
C)I only
D)II only

Question 14

What is the ability of myocardial tissue to propagate electrical impulses?

A)automaticity
B)conductivity
C)contractility
D)excitability

Question 15

Intercalated disks in the myocardium perform a very important function. Which of the following describes that function?

A)absolute refractory period
B)automaticity
C)contractility
D)electrical conduction

Question 16

The apex of the heart (tip of the left ventricle) lies just above the diaphragm at a level corresponding to which intercostal space?

A)fourth
B)fifth
C)sixth
D)seventh

Question 17

Most of the muscle mass of the heart is located in which chamber?

A)left atrium (LA)
B)left ventricle (LV)
C)right atrium (RA)
D)right ventricle (RV)

Question 18

The semilunar (pulmonary and aortic) valves do which of the following?

A)cause almost the entire afterload for the ventricles
B)consist of two half-moon or crescent-shaped cusps
C)prevent arterial backflow during ventricular relaxation
D)separate the ventricles from their arterial outflow tracts

Question 19

Tissue layers making up the heart wall include which of the following?
I)endocardium
II)epicardium
III)myocardium

A)I, II, and III
B)II and III
C)II only
D)I and III

Question 20

Which vessels in the body act like faucets, controlling the flow of blood into the capillary beds?

A)arteries
B)arterioles
C)veins
D)venules

Question 21

Which of the following equations would you use to compute total peripheral resistance (CO = cardiac output)?

A)(mean aortic pressure * right atrial pressure) / CO
B)(mean aortic pressure/right atrial pressure) *CO
C)(mean aortic pressure - right atrial pressure) / CO
D)(right atrial pressure - mean aortic pressure) / CO

Question 22

Which portion of the nervous system is mainly responsible for the central control of the blood flow?

A)higher brain centers
B)parasympathetic nervous system
C)somatic (voluntary) nervous system
D)sympathetic nervous system

Question 23

Which of the following factors determine cardiac stroke volume?
I)ventricular preload
II)ventricular afterload
III)ventricular contractility

A)I and II
B)I and III
C)II and III
D)I, II, and III

Question 24

What is the primary function of local or intrinsic cardiovascular control mechanisms?

A)alter local blood flow according to tissue needs
B)alter the rate of cardiac contractions
C)maintain a basal level of systemic vascular tone
D)control the capacity of the venous reservoir

Question 25

Central, or extrinsic, control of the cardiovascular system occurs through the action of which of the following?
I)autonomic nervous system
II)circulating humoral agents
III)local metabolites

A)I, II, and III
B)II and III
C)III
D)I and II

Question 26

What circulatory system is referred to as a low-pressure, low-resistance system?

A)left heart
B)pulmonary vascular bed
C)right heart
D)systemic vascular bed

Question 27

Variations in blood flow to the brain are governed primarily by which of the following?

A)central neural innervation
B)circulation of humoral agents
C)local metabolic control mechanisms
D)local myogenic control mechanisms

Question 28

The cardiovascular system regulates perfusion mainly by altering which of the following?

A)capacity and resistance of blood vessels
B)rate of cardiac contractions
C)strength of cardiac contractions
D)volume of cardiac contractions

Question 29

During blood loss due to hemorrhage, perfusing pressures can be kept near normal until the volume loss overwhelms the system. Why is this so?

A)Arteries constrict, increasing vascular resistance.
B)Arterioles dilate, decreasing vascular capacity.
C)Muscle vessels dilate, increasing vascular capacity.
D)Venules constrict, decreasing vascular capacity.

Question 30

The underlying goal of the body's cardiovascular control mechanisms is to ensure that all tissues receive which of the following?

A)blood flow according to their mass
B)blood flow according to their size
C)equivalent amounts of blood flow
D)perfusion according to their metabolic needs

Question 31

Which of the following formulas is used to calculate the total amount of blood pumped by the heart per minute, or cardiac output?

A)blood pressure * SV
B)rate * SV
C)SV / rate
D)SV * vascular resistance

Question 32

Central control of vasomotor tone has its greatest impact on which of the following vessels?
I.arterioles (resistance vessels)
II.veins (capacitance vessels)
III.microcirculation (exchange vessels)

A)II and III
B)I and II
C)III only
D)I, II, and III

Question 33

Which of the following equations best portrays the factors determining mean arterial blood pressure?

A)mean arterial pressure = cardiac output / vascular resistance
B)mean arterial pressure = cardiac output * vascular resistance
C)mean arterial pressure = right atrial pressure - aortic pressure
D)mean arterial pressure = vascular resistance / cardiac output

Question 34

Which of the following statements is true?

A)Pulmonary vascular resistance (PVR) is equal to systemic resistance.
B)Pulmonary vasculature is a high-pressure, high-resistance circulation.
C)Systemic vascular resistance (SVR) is less than PVR.
D)SVR is normally approximately 10 times higher than PVR.

Question 35

Variations in blood flow to the heart are governed primarily by which of the following?
I)local metabolic control mechanisms
II)local myogenic control mechanisms
III)central neural innervation

A)I, II, and III
B)II and II
C)I only
D)I and III

Question 36

Central mechanisms cause contraction and increased resistance to blood flow mainly through which of the following?

A)adrenergic stimulation and the release of norepinephrine
B)cholinergic stimulation and the release of acetylcholine
C)cholinergic stimulation and the release of norepinephrine
D)stimulation of specialized $\alpha$ -adrenergic receptors

Question 37

What is an approximate normal resting cardiac output for a healthy adult?

A)75 ml/min
B)500 ml/min
C)2000 ml/min
D)5000 ml/min

Question 38

Mean arterial blood pressure can be regulated by changing which of the following?
I)capacity of the circulatory system
II)effective volume of circulating blood
III)tone of the capacitance vessels (veins)

A)I and II
B)II
C)I, II, and III
D)III

Question 39

Smooth muscle relaxation and vessel dilation are caused mainly by which of the following?
I.action of local metabolites
II.cholinergic stimulation
III.stimulation of $\beta$ -adrenergic receptors

A)I and III
B)II and III
C)I and II
D)I, II, and III

Question 40

During exercise, cardiac output increases dramatically, but mean arterial blood pressure rises very little. Why is this so?

A)Venules constrict, increasing vascular resistance.
B)Arterioles dilate, decreasing vascular capacity.
C)Arterioles constrict, increasing vascular resistance.
D)Muscle vessels dilate, increasing vascular capacity.

Question 41

Which of the following would have a negative impact on cardiac contractility?
I)acidosis
II)digitalis
III)hypoxia
IV)norepinephrine

A)I, II, and III
B)II and IV
C)IV only
D)I and III

Question 42

Significant loss of blood volume causes an increase in which of the following?
I)vascular tone
II)secretion of antidiuretic hormone (ADH)III.heart rate

A)I, II, and III
B)II and III
C)I and III
D)I and II

Question 43

Immediately following the P wave of the electrocardiogram, an A wave appears on both the left and right heart pressure graphs. This A wave corresponds to which of the following?

A)atrial contraction
B)atrioventricular valve closure
C)semilunar valve closure
D)ventricular contraction

Question 44

What does the Frank-Starling law of the heart state?

A)The less cardiac fibers stretch, the greater is the stroke volume.
B)The more cardiac fibers stretch, the greater the stroke volume.
C)The more cardiac fibers stretch, the greater the heart rate.
D)The more cardiac fibers stretch, the less the stroke volume.

Question 45

Opening of the semilunar valves occurs when which of the following occurs?

A)The pressures in the arteries exceed those in the ventricles.
B)The pressures in the atria exceed those in the ventricles.
C)The pressures in the ventricles exceed those in the aorta and pulmonary artery.
D)The pressures in the ventricles exceed those in the atria.

Question 46

During the normal events of the cardiac cycle, which of the following statements is true?

A)Electrical depolarization follows mechanical contraction.
B)Electrical depolarization precedes mechanical contraction.
C)Heart sounds precede electrical depolarization.
D)Heart sounds precede cardiac valve opening or closing.

Question 47

What factor stimulates the carotid and aortic chemoreceptors?

A)high carbon dioxide levels
B)high oxygen levels
C)high pH levels
D)high 2,3-DPG levels

Question 48

Changes in the rate of cardiac contractions are affected primarily by changes in which of the following?

A)sympathetic or parasympathetic tone
B)ventricular afterload
C)ventricular contractility
D)ventricular preload

Question 49

Vascular low-pressure baroreceptors have their greatest impact on which system?

A)central chemoreceptors
B)endocrine
C)exocrine
D)renin-angiotensin

Question 50

Stoke volume can be calculated using which formula?

A)ejection fraction * heart rate
B)end-diastolic volume - end-systolic volume
C)ejection fraction * end-systolic volume
D)cardiac output / end-diastolic volume

Question 51

What is the affect on the cardiovascular medullary centers when the cerebral carbon dioxide is low?

A)excitatory
B)inhibitory
C)no affect

Question 52

Which of the following are true of the force against which the left ventricle must pump?
I)referred to as left ventricular afterload
II)equivalent to systemic vascular resistance
III)helps to determine left ventricular stroke volume

A)I and III
B)I and II
C)I, II, and III
D)II and III

Question 53

What is a normal cardiac ejection fraction?

A) $1 / 4$
B) $1 / 3$
C) $1 / 2$
D) $2 / 3$

Question 54

In order to function effectively, the central cardiovascular control center must receive signals regarding changes in blood volume or pressure. From where do these signals come?

A)central chemoreceptors
B)hypothalamus
C)peripheral baroreceptors
D)skeletal muscles

Question 55

What are the major effects of peripheral chemoreceptor stimulation?

A)decreased drive to breathe
B)decreased production of erythropoietin
C)vasoconstriction and increased heart rate
D)vasodilation and increased stroke volume

Question 56

Given a stroke volume of 40 ml and an end-diastolic volume (EDV) of 70 ml, what is the patient's ejection fraction (EF)?

A)0.57
B)1.75
C)67
D)2800

Question 57

The heart's ability to vary stroke volume based solely on changes in end-diastolic volume is based on what mechanism?

A)automaticity
B)autoregulation
C)Bohr equation
D)Frank-Starling law

Question 58

The first heart sound is associated with what mechanical event of the cardiac cycle?

A)atrioventricular valve closure
B)atrioventricular valve opening
C)semilunar valve closure
D)semilunar valve opening

Question 59

Where are the central centers responsible for regulating the cardiovascular system located?

A)aortic bodies
B)brainstem
C)carotid arteries
D)cerebral hemispheres

Question 60

Considering the negative feedback system for the control of blood pressure, when a blood pressure rise is noted in the arterial receptors, what is the expected response?

A)arterial vasoconstriction
B)decreased inotropic state
C)increased heart rate
D)venoconstriction

Question 61

The semilunar valves close when which of the following occurs?

A)The pressures in the arteries exceed those in the ventricles.
B)The pressures in the ventricles and arteries become equal.
C)The pressures in the atria exceed those in the ventricles.
D)The pressures in the ventricles exceed those in the atria.

Question 62

During the later stages of ventricular relaxation, the pressures in their chambers drop below those in the atria. This results in which of the following?
I)rapid drop in atrial pressures
II)opening of the atrioventricular valves
III)rapid ventricular filling
IV)V pressure wave

A)II and III
B)I and II
C)I, II, III, and IV
D)II, III, and IV

Question 63

The dicrotic notch recorded in the aorta immediately follows what mechanical event of the cardiac cycle?

A)closure of the aortic valve
B)closure of the atrioventricular valves
C)isovolume contraction
D)opening of the aortic valve

Question 64

The second heart sound is associated with what mechanical event of the cardiac cycle?

A)atrioventricular valve closure
B)atrioventricular valve opening
C)semilunar valve closure
D)semilunar valve opening

Question 65

Toward the end of systole, as repolarization starts (indicated by the T wave), the ventricles begin to relax. Which of the following will occur next?

A)rapid rise in ventricular pressures
B)arterial pressures exceed ventricular pressures
C)closure of the atrioventricular valves
D)opening of semilunar valves