NUR 631 Exam 3 2026/2027 – Neuro,
Musculoskeletal & Mental Health
Questions and Answers with Rationales
SECTION I — NEUROLOGIC PHYSIOLOGY & NEUROPATHOPHYSIOLOGY
1. Which structure is primarily responsible for maintaining the resting
membrane potential of a neuron?
A. Sodium-potassium ATPase
B. Calcium pump only
C. Acetylcholinesterase
D. Voltage-gated calcium channels
Answer: A. Sodium-potassium ATPase
Rationale: The sodium-potassium ATPase maintains intracellular
potassium and extracellular sodium gradients essential for neuronal
membrane potential.
2. During neuronal depolarization, which ion rapidly enters the
neuron?
A. Potassium
B. Sodium
C. Chloride
D. Magnesium
Answer: B. Sodium
Rationale: Opening of voltage-gated sodium channels allows sodium
influx, making the membrane potential more positive.
,3. Repolarization of an action potential is primarily associated with:
A. Sodium influx
B. Potassium efflux
C. Calcium influx
D. Chloride efflux
Answer: B. Potassium efflux
Rationale: Voltage-gated potassium channels open after
depolarization, allowing potassium to leave the neuron and restore
membrane negativity.
4. Saltatory conduction occurs in:
A. Unmyelinated axons
B. Myelinated axons
C. Dendrites only
D. Synaptic vesicles
Answer: B. Myelinated axons
Rationale: Action potentials jump between nodes of Ranvier in
myelinated axons, increasing conduction velocity.
5. Which cells produce myelin in the central nervous system?
A. Schwann cells
B. Oligodendrocytes
C. Astrocytes
D. Microglia
Answer: B. Oligodendrocytes
Rationale: Oligodendrocytes myelinate CNS axons, whereas Schwann
cells myelinate peripheral nerves.
6. Which cells produce myelin in the peripheral nervous system?
,A. Schwann cells
B. Oligodendrocytes
C. Microglia
D. Astrocytes
Answer: A. Schwann cells
Rationale: Schwann cells form myelin sheaths around peripheral axons.
7. The primary excitatory neurotransmitter in the CNS is:
A. GABA
B. Glutamate
C. Glycine
D. Serotonin
Answer: B. Glutamate
Rationale: Glutamate is the major excitatory neurotransmitter in the
central nervous system.
8. The major inhibitory neurotransmitter in the brain is:
A. Glutamate
B. GABA
C. Dopamine
D. Acetylcholine
Answer: B. GABA
Rationale: GABA reduces neuronal excitability and is the major
inhibitory neurotransmitter in the brain.
9. Which neurotransmitter is strongly associated with reward,
movement, and motivation?
A. Dopamine
B. GABA
, C. Glycine
D. Histamine
Answer: A. Dopamine
Rationale: Dopamine participates in motor control, reward, motivation,
and several psychiatric disorders.
10. Serotonin is involved in regulation of:
A. Mood, sleep, and appetite
B. Bone mineralization only
C. Renal filtration
D. Oxygen transport
Answer: A. Mood, sleep, and appetite
Rationale: Serotonin regulates mood, sleep, appetite, cognition, and
several autonomic functions.
11. Acetylcholine is important for:
A. Neuromuscular transmission
B. Bone resorption only
C. Hemoglobin synthesis
D. Renal filtration
Answer: A. Neuromuscular transmission
Rationale: Acetylcholine released at the neuromuscular junction
activates skeletal-muscle nicotinic receptors.
12. The blood-brain barrier primarily functions to:
A. Prevent all substances from entering the brain
B. Regulate movement of substances into CNS tissue
C. Produce cerebrospinal fluid
D. Generate action potentials
Musculoskeletal & Mental Health
Questions and Answers with Rationales
SECTION I — NEUROLOGIC PHYSIOLOGY & NEUROPATHOPHYSIOLOGY
1. Which structure is primarily responsible for maintaining the resting
membrane potential of a neuron?
A. Sodium-potassium ATPase
B. Calcium pump only
C. Acetylcholinesterase
D. Voltage-gated calcium channels
Answer: A. Sodium-potassium ATPase
Rationale: The sodium-potassium ATPase maintains intracellular
potassium and extracellular sodium gradients essential for neuronal
membrane potential.
2. During neuronal depolarization, which ion rapidly enters the
neuron?
A. Potassium
B. Sodium
C. Chloride
D. Magnesium
Answer: B. Sodium
Rationale: Opening of voltage-gated sodium channels allows sodium
influx, making the membrane potential more positive.
,3. Repolarization of an action potential is primarily associated with:
A. Sodium influx
B. Potassium efflux
C. Calcium influx
D. Chloride efflux
Answer: B. Potassium efflux
Rationale: Voltage-gated potassium channels open after
depolarization, allowing potassium to leave the neuron and restore
membrane negativity.
4. Saltatory conduction occurs in:
A. Unmyelinated axons
B. Myelinated axons
C. Dendrites only
D. Synaptic vesicles
Answer: B. Myelinated axons
Rationale: Action potentials jump between nodes of Ranvier in
myelinated axons, increasing conduction velocity.
5. Which cells produce myelin in the central nervous system?
A. Schwann cells
B. Oligodendrocytes
C. Astrocytes
D. Microglia
Answer: B. Oligodendrocytes
Rationale: Oligodendrocytes myelinate CNS axons, whereas Schwann
cells myelinate peripheral nerves.
6. Which cells produce myelin in the peripheral nervous system?
,A. Schwann cells
B. Oligodendrocytes
C. Microglia
D. Astrocytes
Answer: A. Schwann cells
Rationale: Schwann cells form myelin sheaths around peripheral axons.
7. The primary excitatory neurotransmitter in the CNS is:
A. GABA
B. Glutamate
C. Glycine
D. Serotonin
Answer: B. Glutamate
Rationale: Glutamate is the major excitatory neurotransmitter in the
central nervous system.
8. The major inhibitory neurotransmitter in the brain is:
A. Glutamate
B. GABA
C. Dopamine
D. Acetylcholine
Answer: B. GABA
Rationale: GABA reduces neuronal excitability and is the major
inhibitory neurotransmitter in the brain.
9. Which neurotransmitter is strongly associated with reward,
movement, and motivation?
A. Dopamine
B. GABA
, C. Glycine
D. Histamine
Answer: A. Dopamine
Rationale: Dopamine participates in motor control, reward, motivation,
and several psychiatric disorders.
10. Serotonin is involved in regulation of:
A. Mood, sleep, and appetite
B. Bone mineralization only
C. Renal filtration
D. Oxygen transport
Answer: A. Mood, sleep, and appetite
Rationale: Serotonin regulates mood, sleep, appetite, cognition, and
several autonomic functions.
11. Acetylcholine is important for:
A. Neuromuscular transmission
B. Bone resorption only
C. Hemoglobin synthesis
D. Renal filtration
Answer: A. Neuromuscular transmission
Rationale: Acetylcholine released at the neuromuscular junction
activates skeletal-muscle nicotinic receptors.
12. The blood-brain barrier primarily functions to:
A. Prevent all substances from entering the brain
B. Regulate movement of substances into CNS tissue
C. Produce cerebrospinal fluid
D. Generate action potentials
