BIOL251 MODULE 4 EXAM REVIEW:
HUMAN ANATOMY & PHYSIOLOGY | 50
QUESTIONS | PORTAGE LEARNING
1. Which neuroglial cell is responsible for the formation of the blood-brain barrier (BBB) by
wrapping its foot processes around capillaries?
A. Ependymal cells
B. Microglia
C. Oligodendrocytes
D. Astrocytes
Answer: D
Conceptual Explanation: Astrocytes are the most abundant glial cells in the CNS and
provide structural support while maintaining the blood-brain barrier through their
perivascular feet.
2. During the repolarization phase of an action potential, which of the following events
occurs?
A. Potassium channels open and potassium flows out of the cell
,B. Sodium channels open rapidly
C. The membrane potential becomes more positive than the threshold
D. Calcium ions enter the axon terminal
Answer: A
Conceptual Explanation: Repolarization involves the closing of voltage-gated sodium
channels and the opening of voltage-gated potassium channels, allowing K+ to exit the cell,
restoring the negative internal charge.
3. The ‘All-or-None’ principle of action potentials states that:
A. A stimulus must reach a threshold of approximately -55mV to trigger a full response
B. Stronger stimuli produce larger action potentials
C. Neurotransmitters are always released in the same quantity
D. All neurons in a nerve must fire at once
Answer: A
Conceptual Explanation: The All-or-None principle means that if a stimulus is strong
enough to reach the threshold (-55mV), an action potential occurs at a constant magnitude;
if not, no action potential occurs.
4. Which part of the brain acts as the primary relay station for all sensory information (except
olfaction) headed to the cerebral cortex?
A. Hypothalamus
, B. Pons
C. Medulla Oblongata
D. Thalamus
Answer: D
Conceptual Explanation: The thalamus is often called the ‘gateway to the cerebral cortex’
because it sorts and edits sensory information before sending it to the higher brain centers.
5. Damage to Broca’s area, located in the frontal lobe of the left hemisphere, would most
likely result in:
A. Inability to understand spoken language
B. Loss of vision in the right eye
C. Inability to coordinate fine motor movements
D. Difficulty in the physical production of speech
Answer: D
Conceptual Explanation: Broca’s area is the motor speech area. Damage results in
expressive aphasia, where the patient understands language but struggles to speak fluently.
6. Which division of the Autonomic Nervous System (ANS) is characterized by long pre-
ganglionic fibers and short post-ganglionic fibers?
A. Sympathetic Division
B. Somatic Nervous System
HUMAN ANATOMY & PHYSIOLOGY | 50
QUESTIONS | PORTAGE LEARNING
1. Which neuroglial cell is responsible for the formation of the blood-brain barrier (BBB) by
wrapping its foot processes around capillaries?
A. Ependymal cells
B. Microglia
C. Oligodendrocytes
D. Astrocytes
Answer: D
Conceptual Explanation: Astrocytes are the most abundant glial cells in the CNS and
provide structural support while maintaining the blood-brain barrier through their
perivascular feet.
2. During the repolarization phase of an action potential, which of the following events
occurs?
A. Potassium channels open and potassium flows out of the cell
,B. Sodium channels open rapidly
C. The membrane potential becomes more positive than the threshold
D. Calcium ions enter the axon terminal
Answer: A
Conceptual Explanation: Repolarization involves the closing of voltage-gated sodium
channels and the opening of voltage-gated potassium channels, allowing K+ to exit the cell,
restoring the negative internal charge.
3. The ‘All-or-None’ principle of action potentials states that:
A. A stimulus must reach a threshold of approximately -55mV to trigger a full response
B. Stronger stimuli produce larger action potentials
C. Neurotransmitters are always released in the same quantity
D. All neurons in a nerve must fire at once
Answer: A
Conceptual Explanation: The All-or-None principle means that if a stimulus is strong
enough to reach the threshold (-55mV), an action potential occurs at a constant magnitude;
if not, no action potential occurs.
4. Which part of the brain acts as the primary relay station for all sensory information (except
olfaction) headed to the cerebral cortex?
A. Hypothalamus
, B. Pons
C. Medulla Oblongata
D. Thalamus
Answer: D
Conceptual Explanation: The thalamus is often called the ‘gateway to the cerebral cortex’
because it sorts and edits sensory information before sending it to the higher brain centers.
5. Damage to Broca’s area, located in the frontal lobe of the left hemisphere, would most
likely result in:
A. Inability to understand spoken language
B. Loss of vision in the right eye
C. Inability to coordinate fine motor movements
D. Difficulty in the physical production of speech
Answer: D
Conceptual Explanation: Broca’s area is the motor speech area. Damage results in
expressive aphasia, where the patient understands language but struggles to speak fluently.
6. Which division of the Autonomic Nervous System (ANS) is characterized by long pre-
ganglionic fibers and short post-ganglionic fibers?
A. Sympathetic Division
B. Somatic Nervous System
