10/15/24, 10:10 TB Chapter 13- Organization and Control of Neural
AM Function
1. The nurse knows which of the following phenomena listed below is an
accurate statement about axonal transport?
A) Anterograde and retrograde axonal transport allow for the communication of
nerve impulses between the neuron and the central nervous system (CNS).
B) Materials can be transported to the nerve terminal by either a fast or
slow component.
C) The unidirectional nature of the axonal transport system protects the CNS
against potential pathogens.
D) Axonal transport facilitates the movement of electrical impulses but precludes
the transport of molecular materials.
Ans: B
Feedback:
The bidirectional axonal transport system allows for the transport of molecular
materials (as opposed to electrical impulses); anterograde transport has both slow and
fast components.
2. An adult male has a new diagnosis of Guillain-Barré syndrome. The nurse knows
which of the following pathophysiological processes underlie the deficits that
accompany the degeneration of myelin in his peripheral nervous system (PNS)?
A) The destruction of myelin causes fewer Schwann cells to be produced in
the client's PNS.
B) The axonal transport system is compromised by the lack of myelin surrounding
nerve cells.
C) Unless remyelination occurs, the axon will eventually die.
D) A deficit of myelin predisposes the client to infection by potential
pathogens. Ans: C
Feedback:
In some pathologic conditions, the myelin may degenerate or be destroyed. This leaves
a section of the axonal process without myelin while leaving the nearby
oligodendroglial or Schwann cells intact. Unless remyelination takes place, the axon
eventually dies. A lack of myelin is associated with reduced insulation and impulse
conduction. Schwann cells produce myelin, not vice versa, and the myelin is
responsible for neither the axonal transport system nor protection against pathogens.
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, 10/15/24, 10:10 TB Chapter 13- Organization and Control of Neural
AM Function
3. While assessing a critically ill patient in the emergency department, the nurse notes on
the cardiac monitor an R-on-T premature ventricular beat that develops into
ventricular tachycardia (VT). Immediately, the patient became unresponsive. The
nurse knows that based on pathophysiologic principles, the most likely cause of the
unresponsiveness is
A) metabolic acidosis that occurs spontaneously following any dysrhythmias.
B) interruption of the blood/oxygen supply to the brain.
C) massive cerebrovascular accident (CVA) resulting from increased perfusion.
D) a blood clot coming from the heart and occluding the carotid
arteries. Ans: B
Feedback:
The brain receives 15% to 20% of the total resting cardiac output and consumes 20% of
its oxygen. The brain cannot store oxygen or engage in anaerobic metabolism. An
interruption of blood or oxygen supply to the brain rapidly leads to clinically observable
signs and symptoms. Unconsciousness occurs almost simultaneously with cardiac
arrest. Metabolic acidosis will occur later in the cardiac arrest but not immediately and
is not responsible for the patient's unresponsiveness. CVAs can be caused by
thrombosis formation or plaque occlusions, but it is not the primary reason for
unconsciousness in VT.
4. When educating a patient about to undergo a pacemaker insertion, the nurse explains
the normal phases of cardiac muscle tissue. During the repolarization phase, the nurse
will stress that membranes must be repolarized before they can be reexcited. Within
the cell, the nurse understands that
A) potassium channels open while sodium channels close, causing repolarization
to the resting state.
B) the influx of calcium is the primary stimulus for the repolarization of
cardiac tissue.
C) only the electrical activity within the heart will determine when
repolarization occurs.
D) the cell membranes need to stay calm resulting in muscle tissue
becoming refractive.
Ans: A
Feedback:
Repolarization is the phase during which the polarity of the resting membrane
potential is reestablished. This occurs with the closure of the sodium channels and
opening of the potassium channels.
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AM Function
1. The nurse knows which of the following phenomena listed below is an
accurate statement about axonal transport?
A) Anterograde and retrograde axonal transport allow for the communication of
nerve impulses between the neuron and the central nervous system (CNS).
B) Materials can be transported to the nerve terminal by either a fast or
slow component.
C) The unidirectional nature of the axonal transport system protects the CNS
against potential pathogens.
D) Axonal transport facilitates the movement of electrical impulses but precludes
the transport of molecular materials.
Ans: B
Feedback:
The bidirectional axonal transport system allows for the transport of molecular
materials (as opposed to electrical impulses); anterograde transport has both slow and
fast components.
2. An adult male has a new diagnosis of Guillain-Barré syndrome. The nurse knows
which of the following pathophysiological processes underlie the deficits that
accompany the degeneration of myelin in his peripheral nervous system (PNS)?
A) The destruction of myelin causes fewer Schwann cells to be produced in
the client's PNS.
B) The axonal transport system is compromised by the lack of myelin surrounding
nerve cells.
C) Unless remyelination occurs, the axon will eventually die.
D) A deficit of myelin predisposes the client to infection by potential
pathogens. Ans: C
Feedback:
In some pathologic conditions, the myelin may degenerate or be destroyed. This leaves
a section of the axonal process without myelin while leaving the nearby
oligodendroglial or Schwann cells intact. Unless remyelination takes place, the axon
eventually dies. A lack of myelin is associated with reduced insulation and impulse
conduction. Schwann cells produce myelin, not vice versa, and the myelin is
responsible for neither the axonal transport system nor protection against pathogens.
Page 1
about:blan 1/
k 10
, 10/15/24, 10:10 TB Chapter 13- Organization and Control of Neural
AM Function
3. While assessing a critically ill patient in the emergency department, the nurse notes on
the cardiac monitor an R-on-T premature ventricular beat that develops into
ventricular tachycardia (VT). Immediately, the patient became unresponsive. The
nurse knows that based on pathophysiologic principles, the most likely cause of the
unresponsiveness is
A) metabolic acidosis that occurs spontaneously following any dysrhythmias.
B) interruption of the blood/oxygen supply to the brain.
C) massive cerebrovascular accident (CVA) resulting from increased perfusion.
D) a blood clot coming from the heart and occluding the carotid
arteries. Ans: B
Feedback:
The brain receives 15% to 20% of the total resting cardiac output and consumes 20% of
its oxygen. The brain cannot store oxygen or engage in anaerobic metabolism. An
interruption of blood or oxygen supply to the brain rapidly leads to clinically observable
signs and symptoms. Unconsciousness occurs almost simultaneously with cardiac
arrest. Metabolic acidosis will occur later in the cardiac arrest but not immediately and
is not responsible for the patient's unresponsiveness. CVAs can be caused by
thrombosis formation or plaque occlusions, but it is not the primary reason for
unconsciousness in VT.
4. When educating a patient about to undergo a pacemaker insertion, the nurse explains
the normal phases of cardiac muscle tissue. During the repolarization phase, the nurse
will stress that membranes must be repolarized before they can be reexcited. Within
the cell, the nurse understands that
A) potassium channels open while sodium channels close, causing repolarization
to the resting state.
B) the influx of calcium is the primary stimulus for the repolarization of
cardiac tissue.
C) only the electrical activity within the heart will determine when
repolarization occurs.
D) the cell membranes need to stay calm resulting in muscle tissue
becoming refractive.
Ans: A
Feedback:
Repolarization is the phase during which the polarity of the resting membrane
potential is reestablished. This occurs with the closure of the sodium channels and
opening of the potassium channels.
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