CCT - Practice Test UPDATE
VERIFIED QUESTIONS & DETAILED
EXPLANATIONS GRADED A+
Professional Academic Assistance Services
1. Which heart chamber functions to pump deoxygenated blood
to the lungs?
a. Right atrium
b. Right ventricle
c. Left atrium
d. Left ventricle - Answer: 1. B: The right ventricle pumps the
deoxygenated blood it has received from the right atrium to the
lungs. The right atrium pumps deoxygenated blood from the
body to the right ventricle. The left atrium pumps oxygenated
blood from the lungs to the left ventricle. The left ventricle
pumps oxygenated blood to the body.
2. Which lead is the most affected by respiration?
a. V2
b. V4
c. Lead III
d. Lead I - Answer: 2. C: Lead III is the most affected by
respiration, and therefore the waveforms may look different
depending on the respiratory cycle. Because of this, a Q wave
that only appears in lead III and is not associated with other
,corresponding changes in other leads is not significant.
3. Which of the following is the correct sequence by which
action potentials are conducted through the heart?"
a. SA node → AV node → bundle branches → Purkinje fibers
b. Bundle branches → Purkinje fibers → SA node → AV node
c. Purkinje fibers → SA node → bundle branches → AV node
d. AV node → SA node → bundle branches → Purkinje fibers -
Answer: 3. A: The sequence by which an action potential is
conducted through the heart is from the sinoatrial (SA) node to
the atrioventricular (AV) node to the bundle branches and then
to the Purkinje fibers.
4. What type of heart block is seen in the following
electrocardiogram (ECG) strip?"
a. First-degree heart block
b. Second-degree heart block, type 1
c. Second-degree heart block, type 2
d. Third-degree heart block - Answer: 4. B: The pictured ECG is a
second-degree heart block, type 1. This rhythm is also called
Mobitz I or Wenckebach. With this heart block the PR interval
gets longer with each beat until eventually a P wave occurs, but
a QRS does not follow (a beat is skipped). After the skipped beat,
the pattern starts over again. A first-degree heart block occurs
, when the PR interval is longer than 0.2 seconds, but the PR
interval generally remains constant and the QRS is not dropped.
A second-degree heart block, type 2, also called Mobitz II, is
apparent when the QRS suddenly fails to show up after a P
wave. A fairly consistent ratio of P waves to QRS complexes is
common, and this rhythm lacks the increasing PR interval that is
seen in the Mobitz I block. A third-degree heart block is also
called a complete heart block and the atria and ventricles beat
independently of one another.
5. When calibrating an ECG machine, what is the standard size
of the calibration mark representing the sensitivity of the ECG
machine?
a. 5 mm in height
b. 10 mm in height
c. 15 mm in height
d. 20 mm in height - Answer: 5. B: The calibration mark
representing the sensitivity of the ECG should be 10 mm in
height (two large squares). This mark is usually found on the left
side of the page at the beginning of each line of the ECG. When
this is set correctly it means that for every millivolt measured
from the patient, a deflection of 10 mm will be recorded on the
trace.
6. Which of the following is the mechanism of action of nitrates?
a. Decrease the responsiveness of heart to the sympathetic
nervous system
VERIFIED QUESTIONS & DETAILED
EXPLANATIONS GRADED A+
Professional Academic Assistance Services
1. Which heart chamber functions to pump deoxygenated blood
to the lungs?
a. Right atrium
b. Right ventricle
c. Left atrium
d. Left ventricle - Answer: 1. B: The right ventricle pumps the
deoxygenated blood it has received from the right atrium to the
lungs. The right atrium pumps deoxygenated blood from the
body to the right ventricle. The left atrium pumps oxygenated
blood from the lungs to the left ventricle. The left ventricle
pumps oxygenated blood to the body.
2. Which lead is the most affected by respiration?
a. V2
b. V4
c. Lead III
d. Lead I - Answer: 2. C: Lead III is the most affected by
respiration, and therefore the waveforms may look different
depending on the respiratory cycle. Because of this, a Q wave
that only appears in lead III and is not associated with other
,corresponding changes in other leads is not significant.
3. Which of the following is the correct sequence by which
action potentials are conducted through the heart?"
a. SA node → AV node → bundle branches → Purkinje fibers
b. Bundle branches → Purkinje fibers → SA node → AV node
c. Purkinje fibers → SA node → bundle branches → AV node
d. AV node → SA node → bundle branches → Purkinje fibers -
Answer: 3. A: The sequence by which an action potential is
conducted through the heart is from the sinoatrial (SA) node to
the atrioventricular (AV) node to the bundle branches and then
to the Purkinje fibers.
4. What type of heart block is seen in the following
electrocardiogram (ECG) strip?"
a. First-degree heart block
b. Second-degree heart block, type 1
c. Second-degree heart block, type 2
d. Third-degree heart block - Answer: 4. B: The pictured ECG is a
second-degree heart block, type 1. This rhythm is also called
Mobitz I or Wenckebach. With this heart block the PR interval
gets longer with each beat until eventually a P wave occurs, but
a QRS does not follow (a beat is skipped). After the skipped beat,
the pattern starts over again. A first-degree heart block occurs
, when the PR interval is longer than 0.2 seconds, but the PR
interval generally remains constant and the QRS is not dropped.
A second-degree heart block, type 2, also called Mobitz II, is
apparent when the QRS suddenly fails to show up after a P
wave. A fairly consistent ratio of P waves to QRS complexes is
common, and this rhythm lacks the increasing PR interval that is
seen in the Mobitz I block. A third-degree heart block is also
called a complete heart block and the atria and ventricles beat
independently of one another.
5. When calibrating an ECG machine, what is the standard size
of the calibration mark representing the sensitivity of the ECG
machine?
a. 5 mm in height
b. 10 mm in height
c. 15 mm in height
d. 20 mm in height - Answer: 5. B: The calibration mark
representing the sensitivity of the ECG should be 10 mm in
height (two large squares). This mark is usually found on the left
side of the page at the beginning of each line of the ECG. When
this is set correctly it means that for every millivolt measured
from the patient, a deflection of 10 mm will be recorded on the
trace.
6. Which of the following is the mechanism of action of nitrates?
a. Decrease the responsiveness of heart to the sympathetic
nervous system
