Ch. 18
1) Normal heart sounds are caused by which of the following events?
A) excitation of the SA node
B) closure of the heart valves
C) friction of blood against the chamber walls
D) opening
and closing of the heart valves
B
2) Which of the events below does not occur when the semilunar valves are open?
A) Ventricles are in diastole.
B) Blood enters pulmonary
arteries and the aorta.
C) AV valves are closed.
D)
Ventricles are in systole.
A
3) Hemorrhage with a large loss of blood causes ________.
A) a lowering of blood pressure due to change in cardiac output
B) a rise in blood pressure due to change in cardiac output
C) no change in blood pressure but a slower heart rate
D)
no change in blood pressure but a change in respiration
A
4) The left ventricular wall of the heart is thicker than the right wall in order to ________.
A) accommodate a greater volume of blood
B) expand the
thoracic cage during diastole
C) pump blood with greater
pressure
D) pump blood through a smaller valve
C
5) Damage to the ________ is referred to as heart block.
A) SA node
B) AV valves
C) AV bundle
D) AV node
D
6) The P wave of a normal electrocardiogram indicates ________.
A) ventricular repolarization
B) ventricular
depolarization
C) atrial repolarization
D) atrial depolarization
D
7) Blood within the pulmonary veins returns to the ________.
A) right atrium
B) left atrium
C) right ventricle
D) left ventricle
B
8) Small muscle masses attached to the chordae tendineae are the
________.
A) trabeculae carneae
B) pectinate muscles
C)
papillary muscles
D) venae cavae
C
9) The term for pain associated with deficient blood delivery to the
heart that may be caused by the transient spasm of coronary arteries
is ________.
A) ischemia
B) pericarditis
C) myocardial infarct
D) angina pectoris
D
10) To auscultate the aortic semilunar valve, you would place your
stethoscope in the ________.
A) second intercostal space to the right of the sternum
B)
second intercostal space to the left of the sternum
C) fifth
intercostal space inferior to the left nipple
D) fifth right
intercostal space
A
11) The source of blood carried to capillaries in the myocardium
would be the ________.
A) coronary sinus
B) fossa ovalis
C) coronary
arteries
D) coronary veins
C
12) The fact that the left ventricle of the heart is thicker than the
right ventricle reveals that it ________.
A) pumps a greater volume of blood
B) pumps blood against
a greater resistance
C) expands the thoracic cage
D) sends
blood through a smaller valve
B
13) Which of the following factors does not influence heart rate?
A) skin color
B) age
C) gender
D) body temperature
A
14) Which of the following is not an age-related change affecting the
heart?
A) atherosclerosis
B) decline in cardiac reserve
C)
fibrosis of cardiac muscle
D) thinning of the valve flaps
D
15) If cardiac muscle is deprived of its normal blood supply, damage
would primarily result from ________.
A) decreased delivery of oxygen
B) a decrease in the
number of available mitochondria for energy production
C) a lack
of nutrients to feed into metabolic pathways
D) an inadequate
supply of lactic acid
A
16) If the length of the absolute refractory period in cardiac muscle
cells was the same as it is for skeletal muscle cells ________.
A) it would be much longer before cardiac cells could respond to
a second stimulation
B) contractions would last as long as the
refractory period
C) tetanic contractions might occur, which
would stop the heart's pumping action
D) it would be less than
12 ms
C
17) Norepinephrine acts on the heart by ________.
A) decreasing heart contractility
B) causing a decrease in
stroke volume
C) blocking the action of calcium
D) causing
threshold to be reached more quickly
D
18) If the vagal nerves to the heart were cut, the result would be
that ________.
A) the heart would stop, since the vagal nerves trigger the
heart to contract
B) the heart rate would increase by about 25
beats per minute
C) the AV node would become the pacemaker of
the heart
D) parasympathetic stimulation would increase, causing
a decrease in heart rate
B
19) Foramen ovale ________.
A) connects the two atria in the fetal heart
B) is a
condition in which the heart valves do not completely close
C)
is a shallow depression in the interventricular septum
D) is a
connection between the pulmonary trunk and the aorta in the fetus
A
20) Which vessel of the heart receives blood during right ventricular
systole?
A) venae cavae
B) pulmonary trunk
C) aorta
D)
pulmonary veins
B
21) Which of these vessels receives blood during ventricular systole?
A) aorta only
B) pulmonary arteries only
C)
pulmonary veins only
D) both the aorta and pulmonary trunk
D
22) Which of the following is not part of the conduction system of
the heart?
A) AV node
B) bundle of His
C) AV valve
D) SA node
C
23) The tricuspid valve is closed ________.
A) while the ventricle is in diastole
B) when the
ventricle is in systole
C) while the atrium is contracting
D) by the movement of blood from atrium to ventricle
B
24) When viewing a dissected heart, it is easy to visually discern
the right and left ventricles by ________.
A) tracing out where the auricles connect
B) noticing the
thickness of the ventricle walls
C) locating the apex
D)
finding the papillary muscles
B
25) Select the correct statement about the heart valves.
A) The mitral valve separates the right atrium from the right
ventricle.
B) The tricuspid valve divides the left atrium from
the left ventricle.
C) Aortic and pulmonary valves control the
flow of blood into the heart.
D) The AV valves are supported by
chordae tendineae so that regurgitation of blood into the atria during
ventricular contraction does not occur.
D
26) Select the correct statement about the function of myocardial
cells.
A) The entire heart contracts as a unit or it does not contract
at all.
B) Each cardiac muscle cell is innervated by a
sympathetic nerve ending so that the nervous system can increase heart
rate.
C) The refractory period in skeletal muscle is much longer
than that in cardiac muscle.
D) The influx of potassium ions
from extracellular sources is the initiating event in cardiac muscle contraction.
A
27) Select the correct statement about the structure of the heart
wall.
A) The fibrous skeleton forms the bulk of the heart.
B)
Connective tissue in the heart wall aids in the conduction of the
action potential.
C) The heart chambers are lined by the
endomysium.
D) The myocardium is the layer of the heart that
actually contracts.
D
28) Compared to skeletal muscle, cardiac muscle ________.
A) has gap junctions that allow it to act as a functional
syncytium
B) lacks striations
C) has more nuclei per cell
D) cells are larger than skeletal muscle cells
A
29) During the period of ventricular filling ________.
A) pressure in the heart is at its peak
B) blood flows
passively through the atria and the open AV valves into the ventricles
C) the atria remain in diastole
D) it is represented by
the P wave on the ECG
B
30) The second heart sound is heard during which phase of the cardiac
cycle?
A) isovolumetric relaxation
B) isovolumetric contraction
C) ventricular ejection
D) ventricular filling
A
31) The time of day most hazardous for heart attacks is ________.
A) morning
B) noontime
C) evening
D) during sleep
A
32) If we were able to artificially alter the membrane permeability
of pacemaker cells so that sodium influx is more rapid, ________.
A) threshold is reached more quickly and heart rate would
increase
B) potassium channels compensate and no change in heart
rate would occur
C) heart rate would decrease, but blood
pressure would rise due to the excess sodium present
D) tetanic
contraction would occur due to the short absolute refractory period of
cardiac muscle
A
33) Select the correct statement about cardiac output.
A) A slow heart rate increases end diastolic volume, stroke
volume, and force of contraction.
B) Decreased venous return
will result in increased end diastolic volume.
C) If a semilunar
valve were partially obstructed, the end systolic volume in the
affected ventricle would be decreased.
D) Stroke volume
increases if end diastolic volume decreases.
A
34) During contraction of heart muscle cells ________.
A) the action potential is initiated by voltage-gated slow
calcium channels
B) some calcium enters the cell from the
extracellular space and triggers the release of larger amounts of
calcium from intracellular stores
C) the action potential is
prevented from spreading from cell to cell by gap junctions
D)
calcium is prevented from entering cardiac fibers that have been stimulated
B
35) Isovolumetric contraction ________.
A) refers to the short period during ventricular systole when
the ventricles are completely closed chambers
B) occurs while
the AV valves are open
C) occurs immediately after the aortic
and pulmonary valves close
D) occurs only in people with heart
valve defects
A
36) Commotio cordis is heart failure due to a ________.
A) mild electrical shock to the heart itself
B) severe
electrical shock to the body
C) relatively mild blow to the
chest that occurs during a vulnerable interval (2 ms) when the heart
is repolarizing
D) loss of blood from an artery
C