Transcript Chapter 20 - FacultyWeb

The region between the two pleural cavities
that contains the heart and great vessels is
called the ______?
1.
2.
3.
4.
Mediastinum
Visceral pericardium
Parietal pericardium
Pericardial cavity
Which layer of pericardium touches the heart?
1.
2.
3.
4.
Parietal pericardium
Pericardial sac
Fibrous pericardium
Visceral pericardium
Which of the following is true of cardiac muscle
tissue?
1. Cardiac muscle cells are larger than skeletal
muscle cells.
2. Cardiac muscle is not striated.
3. Cardiac muscle cells have intercalated discs.
4. Cardiac muscle cells are multinucleate.
Which blood vessels bring blood back into
the right atrium from systemic circulation?
1. Foramen ovale, pulmonary trunk, and ductus
arteriosus
2. Superior and inferior venae cavae
3. Superior and inferior venae cavae and
coronary sinus
4. Aorta, pulmonary trunk, and pulmonary veins
How is eversion of the AV valves and backflow of
blood into the atria prevented?
1.
2.
3.
4.
Pressure of blood pushing against the valves
Contraction of the ventricles
Closure of the semilunar valves
Tightening of chordae tendineae and
contraction of papillary muscles
Doris was born with a malformed pulmonary
valve. How will that affect her circulation?
1.
2.
3.
4.
Blood will flow more efficiently into her pulmonary
trunk.
Blood will regurgitate into her right atrium.
Blood will flow back into her right ventricle.
Deoxygenated blood will continuously pass around
her systemic circuit.
Why is the left ventricle more muscular
than the right ventricle?
1. Because it pumps a larger volume of blood.
2. Because it contracts with force sufficient to
push blood through the systemic circuit.
3. Because the papillary muscles are stronger.
4. Both 1 and 2 are correct
Rick had a heart attack because of blockage of his
right coronary artery. Which regions of his heart
will be damaged by the blockage?
1.
2.
3.
4.
SA node and AV node
Interventricular septum and left atrium
Portions of both ventricles
1 and 3 are correct.
Why is resting HR somewhat slower than the 80–
100 bpm set by the SA node?
1. The AV node slows the heart to an average
between its own rate and that of the SA node.
2. Parasympathetic innervation slows the HR.
3. The AV node takes over causing the HR to be
40–60 bpm.
4. None of these is correct.
What is the importance of the 100 msec delay at
the AV node?
1. Atria must contract before the ventricles.
2. AV valves must have time to close.
3. Contraction of papillary muscles must begin
before ventricular contraction.
4. Tachycardia results if the delay is absent.
On an ECG reading, what does the P Wave
indicate?
1.
2.
3.
4.
Ventricular contraction
An abnormal heart condition
Atrial depolarization
Atrial diastole
What factor could cause an increase in the size of
the QRS complex of an electrocardiogram
recording?
1.
2.
3.
4.
An increase in heart rate
A decrease in blood volume
A decrease in blood pressure
An increase in heart size
What condition contributes to a reduction in the
size of the T Wave?
1.
2.
3.
4.
Long-term high fat intake
Damage to the conducting pathway
Damage to the AV node
Coronary ischemia
Why is there no wave corresponding to atrial
repolarization on an ECG reading?
1. It is masked by the QRS complex.
2. Atrial repolarization produces no electrical
effect at all.
3. It is masked by the P Wave.
4. None of these is correct.
What event is taking place during the Q-T interval?
1. A single cycle of the cardiac cycle
2. An action potential
3. A single cycle of atrial depolarization and
repolarization
4. A single cycle of ventricular depolarization
and repolarization
What is happening during ventricular systole of the
cardiac cycle?
1.
2.
3.
4.
Rising atrial pressures push blood into the
ventricles.
All heart valves are closed and ventricles are
relaxing.
Both ventricular contraction and atrial diastole take
place.
Pressure in ventricles drops, which forces the
semilunar valves closed.
When during the cardiac cycle do ventricles
contain their maximal amount of blood? What is
this quantity called?
1.
2.
3.
4.
At the end of ventricular systole/ESV
At the end of atrial systole/EDV
At the end of ventricular diastole/EDV
2 and 3 are correct.
How is Cardiac Output (CO) calculated?
1.
2.
3.
4.
CO ml/min = (EDV–ESV) x SV
CO ml/min = HR bpm x SV ml/beat
CO ml/min = ESV/EDV
1 and 2 are correct
Benjamin has an EDV of 120 ml, an ESV of 45 ml,
which gives him an SV of 75 ml. What is his
ejection fraction?
1.
2.
3.
4.
45%
75%
37.5%
60%
What is the most important factor in considering
cardiac function over time?
1.
2.
3.
4.
Cardiac output
Heart rate
Stroke volume
End systolic volume
Where is the ANS headquarters for cardiovascular
control?
1.
2.
3.
4.
Cardiac plexus
SA and AV nodes
Medulla oblongata
Cervical and upper thoracic ganglia
How does damage to the cardioinhibitory center of
the medulla affect heart rate? Why?
1.
2.
3.
4.
Heart rate increases/sympathetic dominance
Heart rate decreases/parasympathetic dominance
Heart rate remains unchanged/autonomic tone
makes delicate adjustments
Heart rate increases/only the SA node will be
controlling heart rate
What is the effect on heart rate of NE binding to
beta-1 receptors?
1.
2.
3.
4.
Increases rate of depolarization
Decreases heart rate
Increases heart rate
1 and 3 are correct
Which of the following affect(s) the rate of venous
return?
1.
2.
3.
4.
Cardiac output
Stroke volume
Heart rate
All of the above are correct
Frank has just run a marathon and his heart is
beating extremely rapidly. What happens to the
length of diastole and filling time?
1. Both increase
2. Both decrease
3. Length of diastole increases/filling time
decreases
4. Length of diastole decreases/filling time
increases
Why is ESV lower when you are actively
exercising?
1.
2.
3.
4.
SV decreases and filling time increases.
EDV is very low and ventricular muscle is
stretched very little.
EDV increases and ventricular muscle produces
more forceful contractions ejecting more blood.
Parasympathetic stimulation causes it.