BIOL251 MODULE 4: NERVOUS SYSTEM
EXAM REVIEW| 50 QUESTIONS |
PORTAGE LEARNING
1. Which of the following neuroglial cells is responsible for forming the blood-brain barrier by
wrapping around capillaries?
A. Microglia
B. Oligodendrocytes
C. Astrocytes
D. Ependymal cells
Answer: C
Conceptual Explanation: Astrocytes are star-shaped cells in the CNS that provide
structural support and help form the blood-brain barrier by regulating the passage of
substances from the blood to the brain.
2. During the depolarization phase of an action potential, which of the following events
occurs?
A. Potassium channels open and potassium rushes out of the cell.
,B. Voltage-gated sodium channels open and sodium rushes into the cell.
C. Sodium channels close and the sodium-potassium pump stops.
D. The membrane potential becomes more negative than the resting potential.
Answer: B
Conceptual Explanation: Depolarization is characterized by a rapid influx of sodium ions
into the neuron through voltage-gated channels, making the interior less negative.
3. The ‘All-or-None’ principle of nerve impulse conduction states that:
A. All stimuli will result in an action potential regardless of strength.
B. A neuron will fire at maximum strength or not at all once threshold is reached.
C. Only myelinated neurons can produce an action potential.
D. Stronger stimuli produce larger action potentials than weaker stimuli.
Answer: B
Conceptual Explanation: The all-or-none principle means that if a stimulus is strong
enough to reach the threshold, an action potential of constant magnitude is generated.
4. Which part of the brain is primarily responsible for coordinating skilled motor movements
and maintaining posture?
A. Cerebrum
B. Cerebellum
, C. Thalamus
D. Medulla Oblongata
Answer: B
Conceptual Explanation: The cerebellum processes input from the motor cortex and
sensory receptors to provide precise timing and appropriate patterns of skeletal muscle
contraction.
5. Damage to the Wernicke’s area in the left temporal lobe would most likely result in:
A. Inability to move the right arm.
B. Inability to produce speech sounds (motor speech).
C. Inability to understand spoken or written language.
D. Loss of vision in the left eye.
Answer: C
Conceptual Explanation: Wernicke’s area is critical for language comprehension. Damage
results in fluent but nonsensical speech and difficulty understanding others.
6. The primary somatosensory cortex is located in which lobe of the cerebrum?
A. Frontal Lobe
B. Parietal Lobe
C. Temporal Lobe
EXAM REVIEW| 50 QUESTIONS |
PORTAGE LEARNING
1. Which of the following neuroglial cells is responsible for forming the blood-brain barrier by
wrapping around capillaries?
A. Microglia
B. Oligodendrocytes
C. Astrocytes
D. Ependymal cells
Answer: C
Conceptual Explanation: Astrocytes are star-shaped cells in the CNS that provide
structural support and help form the blood-brain barrier by regulating the passage of
substances from the blood to the brain.
2. During the depolarization phase of an action potential, which of the following events
occurs?
A. Potassium channels open and potassium rushes out of the cell.
,B. Voltage-gated sodium channels open and sodium rushes into the cell.
C. Sodium channels close and the sodium-potassium pump stops.
D. The membrane potential becomes more negative than the resting potential.
Answer: B
Conceptual Explanation: Depolarization is characterized by a rapid influx of sodium ions
into the neuron through voltage-gated channels, making the interior less negative.
3. The ‘All-or-None’ principle of nerve impulse conduction states that:
A. All stimuli will result in an action potential regardless of strength.
B. A neuron will fire at maximum strength or not at all once threshold is reached.
C. Only myelinated neurons can produce an action potential.
D. Stronger stimuli produce larger action potentials than weaker stimuli.
Answer: B
Conceptual Explanation: The all-or-none principle means that if a stimulus is strong
enough to reach the threshold, an action potential of constant magnitude is generated.
4. Which part of the brain is primarily responsible for coordinating skilled motor movements
and maintaining posture?
A. Cerebrum
B. Cerebellum
, C. Thalamus
D. Medulla Oblongata
Answer: B
Conceptual Explanation: The cerebellum processes input from the motor cortex and
sensory receptors to provide precise timing and appropriate patterns of skeletal muscle
contraction.
5. Damage to the Wernicke’s area in the left temporal lobe would most likely result in:
A. Inability to move the right arm.
B. Inability to produce speech sounds (motor speech).
C. Inability to understand spoken or written language.
D. Loss of vision in the left eye.
Answer: C
Conceptual Explanation: Wernicke’s area is critical for language comprehension. Damage
results in fluent but nonsensical speech and difficulty understanding others.
6. The primary somatosensory cortex is located in which lobe of the cerebrum?
A. Frontal Lobe
B. Parietal Lobe
C. Temporal Lobe
