1. Which of the following best describes the primary function of the nervous system?
A) To regulate body temperature through hormone release
B) To receive sensory input, integrate information, and produce motor responses
C) To filter waste products from the bloodstream
D) To produce red blood cells in response to hypoxia
Correct Answer: To receive sensory input, integrate information, and produce motor responses
Rationale: The nervous system acts as the body's control center, receiving sensory input from internal
and external environments, integrating this information, and coordinating an appropriate motor or
behavioral response. Hormonal regulation is primarily an endocrine function, filtration occurs in the
kidneys, and red blood cell production is stimulated by erythropoietin.
2. What are the two major anatomical divisions of the nervous system?
A) Somatic and autonomic
B) Central and peripheral
C) Sympathetic and parasympathetic
D) Afferent and efferent
Correct Answer: Central and peripheral
Rationale: The nervous system is divided into the central nervous system (CNS), comprising the brain
and spinal cord, and the peripheral nervous system (PNS), which includes spinal nerves, cranial nerves,
and ganglia. The somatic and autonomic divisions are subdivisions of the PNS, and afferent/efferent
describe functional directions of nerve impulses.
3. Which structures are found within the central nervous system (CNS)?
A) Spinal nerves and cranial nerves
B) Ganglia and peripheral nerves
,C) The brain and spinal cord
D) Sensory receptors and motor endings
Correct Answer: The brain and spinal cord
Rationale: The CNS is composed of the brain and spinal cord, which serve as the integration and
command centers. Spinal nerves, cranial nerves, and ganglia are part of the peripheral nervous system.
4. What structures are found in the peripheral nervous system (PNS)?
A) The brain and spinal cord
B) Spinal nerves, cranial nerves, and ganglia
C) The thalamus and hypothalamus
D) The cerebellum and brainstem
Correct Answer: Spinal nerves, cranial nerves, and ganglia
Rationale: The PNS consists of all neural tissue outside the CNS, including spinal nerves, cranial nerves,
and ganglia. The brain, spinal cord, thalamus, hypothalamus, cerebellum, and brainstem are all
components of the CNS.
5. The somatic nervous system can be further divided into which two subdivisions?
A) Afferent and efferent
B) Sympathetic and parasympathetic
C) Central and peripheral
D) Sensory and motor
Correct Answer: Sympathetic and parasympathetic
, Rationale: The autonomic nervous system, a division of the PNS, is subdivided into the sympathetic and
parasympathetic divisions. The somatic nervous system controls voluntary movements.
Afferent/efferent describe directional flow, not subdivisions of the somatic system.
6. During the resting membrane potential, which of the following is true regarding ion channels?
A) Sodium and potassium gates are both open
B) Sodium gates are open; potassium gates are closed
C) Sodium gates are closed; potassium gates are open
D) Both sodium and potassium gates are closed
Correct Answer: Both sodium and potassium gates are closed
Rationale: During the resting phase, both sodium and potassium voltage-gated channels are closed,
maintaining the resting membrane potential. Depolarization occurs when sodium gates open, and
repolarization involves potassium gates opening.
7. What occurs during the depolarization phase of an action potential?
A) Potassium gates open and potassium rushes out of the axon
B) Sodium gates open and sodium rushes into the axon
C) Both sodium and potassium gates remain closed
D) The membrane potential becomes more negative
Correct Answer: Sodium gates open and sodium rushes into the axon
Rationale: During depolarization, sodium gates open, and sodium ions rush into the axon, causing the
membrane potential to rise from negative toward zero and up to approximately +40 mV. Potassium
efflux occurs during repolarization, not depolarization.
8. What is the term for the brief period after an action potential when a neuron cannot generate
another action potential?
A) Resting potential