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APHY 201- Quiz 2 Questions and Correct
Answers/ Latest Update / Already Graded
Which of the following factors is associated with increased conduction
velocity in an axon?
A. Large diameter
B. Small diameter
C. Increased number of dendrites
D. The absence of the myelin sheath
E. Presence of collaterals
Ans: A. Large diameter
The hyperpolarization phase of the AP is caused by too much ________
leaving the cell.
A. Ca2+
B. Water
C. Na+
D. K+
Ans: D. K+
Which of the following is NOT a characteristic of neurons?
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A. In general, neurons cannot be replaced if destroyed
B. Neurons are relatively small, simple-structured cells
C. Neurons can function optimally for over 100 years
D. Neurons require continuous and abundant supplies of oxygen, and
cannot survive for more than a few minutes without it
Ans: B. Neurons are relatively small, simple-structured cells
Which of the following is characteristic of an action potential?
A. Travels a short distance
B. Absent of positive feedback
C. Voltage-gated ion channels
D. Occurs in the dendrites and cell body
Ans: C. Voltage-gated ion channels
The principal cause of depolarization of a nerve fiber when threshold is
reached is
A. An increase in the outward conductance of Na+
B. An increase in the inward conductance of Na+
C. A decrease in the inward conductance of Na+
D. An increase in the inward conductance of K+
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Ans: B. An increase in the inward conductance of Na+
Excitatory postsynaptic potentials occur when a neurotransmitter
engages a postsynaptic membrane receptor resulting in the
membrane:
A. Becoming less permeable to Na+ in
B. Becoming more permeable to K+ out
C. Becoming more permeable to Na+ in
D. Becoming more permeable to Cl- in
Ans: C. Becoming more permeable to Na+ in
What is the direction of the driving forces for the movement of sodium
ions at the peak of the action potential spike?
A. Outward electrical gradient and outward chemical gradient
B. Outward electrical gradient and inward chemical gradient
C. Inward electrical gradient and inward chemical gradient
D. Outward chemical gradient and outward electrical gradient
Ans: B. Outward electrical gradient and inward chemical
gradient
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Which of the following membrane ion channels in the neuron are
always open?
A. Mechanically gated channels
B. Ligand-gated channels
C. Voltage-gated channels
D. Leakage channels
Ans: D. Leakage channels
The resting membrane potential of a neuron is dependent on:
A. Active transport of potassium ions out of the cell
B. The opening of electrically operated sodium channel gates
C. Active transport of sodium ions into the cell
D. The presence of non-diffusible anions inside the cell
Ans: D. The presence of non-diffusible anions inside the cell
Which of the following statements best describes the resting
membrane state in the neuron?
A. Only the voltage-gated K+ channels are open
B. All of the voltage-gated Na+ and K+ channels are closed
C. Only the voltage-gated Na+ channels are open
All rights reserved © 2025/ 2026 |
APHY 201- Quiz 2 Questions and Correct
Answers/ Latest Update / Already Graded
Which of the following factors is associated with increased conduction
velocity in an axon?
A. Large diameter
B. Small diameter
C. Increased number of dendrites
D. The absence of the myelin sheath
E. Presence of collaterals
Ans: A. Large diameter
The hyperpolarization phase of the AP is caused by too much ________
leaving the cell.
A. Ca2+
B. Water
C. Na+
D. K+
Ans: D. K+
Which of the following is NOT a characteristic of neurons?
All rights reserved © 2025/ 2026 |
, Page |2
A. In general, neurons cannot be replaced if destroyed
B. Neurons are relatively small, simple-structured cells
C. Neurons can function optimally for over 100 years
D. Neurons require continuous and abundant supplies of oxygen, and
cannot survive for more than a few minutes without it
Ans: B. Neurons are relatively small, simple-structured cells
Which of the following is characteristic of an action potential?
A. Travels a short distance
B. Absent of positive feedback
C. Voltage-gated ion channels
D. Occurs in the dendrites and cell body
Ans: C. Voltage-gated ion channels
The principal cause of depolarization of a nerve fiber when threshold is
reached is
A. An increase in the outward conductance of Na+
B. An increase in the inward conductance of Na+
C. A decrease in the inward conductance of Na+
D. An increase in the inward conductance of K+
All rights reserved © 2025/ 2026 |
, Page |3
Ans: B. An increase in the inward conductance of Na+
Excitatory postsynaptic potentials occur when a neurotransmitter
engages a postsynaptic membrane receptor resulting in the
membrane:
A. Becoming less permeable to Na+ in
B. Becoming more permeable to K+ out
C. Becoming more permeable to Na+ in
D. Becoming more permeable to Cl- in
Ans: C. Becoming more permeable to Na+ in
What is the direction of the driving forces for the movement of sodium
ions at the peak of the action potential spike?
A. Outward electrical gradient and outward chemical gradient
B. Outward electrical gradient and inward chemical gradient
C. Inward electrical gradient and inward chemical gradient
D. Outward chemical gradient and outward electrical gradient
Ans: B. Outward electrical gradient and inward chemical
gradient
All rights reserved © 2025/ 2026 |
, Page |4
Which of the following membrane ion channels in the neuron are
always open?
A. Mechanically gated channels
B. Ligand-gated channels
C. Voltage-gated channels
D. Leakage channels
Ans: D. Leakage channels
The resting membrane potential of a neuron is dependent on:
A. Active transport of potassium ions out of the cell
B. The opening of electrically operated sodium channel gates
C. Active transport of sodium ions into the cell
D. The presence of non-diffusible anions inside the cell
Ans: D. The presence of non-diffusible anions inside the cell
Which of the following statements best describes the resting
membrane state in the neuron?
A. Only the voltage-gated K+ channels are open
B. All of the voltage-gated Na+ and K+ channels are closed
C. Only the voltage-gated Na+ channels are open
All rights reserved © 2025/ 2026 |
