Exam 3: BIOS251 / BIOS 251 (Latest Update 2026 /
2027)
Anatomy & Physiology I with Lab | Review Questions with Verified Answers | 100% Correct |
Grade A
Chamberlain University Curriculum Standards
Section 1: Nervous System (Questions 1-35)
Central & Peripheral Nervous System, Brain Regions, Spinal Cord, Cranial Nerves, Autonomic Nervous System,
Neurophysiology
Q1: A nursing student is studying the divisions of the nervous system. Which of the following correctly
describes the functional division that carries sensory information from receptors to the central nervous system?
A. Motor (efferent) division
B. Sensory (afferent) division [CORRECT]
C. Autonomic division only
D. Somatic motor division
Correct Answer: B
Rationale: The sensory (afferent) division transmits sensory input from peripheral receptors toward the CNS for
processing. The motor (efferent) division carries motor commands from the CNS to effectors. The autonomic and somatic
motor divisions are both subdivisions of the motor (efferent) division, not sensory pathways. This distinction between
afferent and efferent pathways is foundational to understanding neural communication in the BIOS 251 curriculum.
Q2: A patient presents with dilated pupils, increased heart rate, and bronchodilation after a stressful event.
Which division of the autonomic nervous system is primarily responsible for these 'fight-or-flight' responses?
A. Parasympathetic division
B. Sympathetic division [CORRECT]
C. Somatic motor division
D. Enteric nervous system
Correct Answer: B
Rationale: The sympathetic division of the ANS mediates the 'fight-or-flight' response, producing pupil dilation
(mydriasis), increased heart rate, bronchodilation, decreased GI motility, and glycogenolysis. It originates from the
thoracolumbar region (T1-L2) of the spinal cord. The parasympathetic division produces the opposite 'rest-and-digest'
effects. The somatic motor division controls voluntary skeletal muscle, and the enteric nervous system regulates the GI
tract independently.
Q3: Which neurotransmitter is released by postganglionic neurons in the sympathetic division at most target
organs?
A. Acetylcholine (ACh)
B. Dopamine
C. Norepinephrine (NE) [CORRECT]
,BIOS 251 Anatomy & Physiology I | Exam 3 Review | Chamberlain University 2026/2027
D. Serotonin
Correct Answer: C
Rationale: In the sympathetic division, preganglionic fibers release ACh (acting on nicotinic receptors in the ganglia),
while postganglionic fibers release norepinephrine (NE) at most target organs, acting on alpha and beta adrenergic
receptors. The exception is sweat glands, where postganglionic sympathetic fibers release ACh. Acetylcholine is the
neurotransmitter used by both pre- and postganglionic fibers in the parasympathetic division, not the sympathetic division
at target organs.
Q4: A patient has a tumor compressing the left cranial nerve III (oculomotor). Which of the following deficits
would the nurse expect to find?
A. Loss of the pupillary light reflex on the ipsilateral side [CORRECT]
B. Inability to abduct the eye laterally
C. Loss of sensation from the cornea
D. Inability to shrug the shoulder
Correct Answer: A
Rationale: Cranial nerve III (oculomotor) controls most extraocular eye movements (superior, inferior, and medial rectus;
inferior oblique), levator palpebrae superioris, and parasympathetic innervation to the sphincter pupillae muscle (pupil
constriction) and ciliary muscle (accommodation). Compression of CN III would cause ptosis, lateral deviation of the eye
(due to unopposed lateral rectus action by CN VI), and loss of the pupillary light reflex. Abduction is controlled by CN VI
(abducens), corneal sensation by CN V (trigeminal), and shoulder shrug by CN XI (accessory).
Q5: A neurologist tests a patient's patellar (knee-jerk) reflex by tapping the patellar tendon. Which type of
reflex is this, and how many synapses are involved?
A. Polysynaptic reflex involving multiple interneurons
B. Monosynaptic stretch reflex with a single synapse [CORRECT]
C. A visceral reflex mediated by the autonomic nervous system
D. A crossed-extensor reflex requiring both sides of the spinal cord
Correct Answer: B
Rationale: The patellar reflex is a monosynaptic stretch reflex. When the patellar tendon is tapped, the muscle spindles in
the quadriceps femoris are stretched, sending afferent signals via sensory neurons to the spinal cord, where they synapse
directly onto alpha motor neurons that cause the quadriceps to contract. There is only one synapse between the sensory
neuron and the motor neuron, making it monosynaptic. Polysynaptic reflexes like the withdrawal reflex involve at least
one interneuron. The crossed-extensor reflex involves coordination between both sides of the spinal cord.
Q6: Which of the following correctly describes the anatomical organization of the spinal cord?
A. Gray matter is located peripherally; white matter is centrally located
B. The spinal cord extends from the foramen magnum to the sacrum
C. Gray matter is centrally located in a butterfly shape; white matter forms peripheral tracts
[CORRECT]
D. Dorsal roots carry motor fibers; ventral roots carry sensory fibers
Correct Answer: C
Rationale: In the spinal cord, gray matter (containing neuron cell bodies) is centrally located and has a butterfly or
H-shaped appearance in cross-section. White matter (myelinated tracts) surrounds the gray matter peripherally. The spinal
cord extends from the foramen magnum to approximately the L1-L2 vertebral level, not the sacrum. Dorsal (posterior)
roots carry sensory (afferent) fibers, while ventral (anterior) roots carry motor (efferent) fibers, which is the opposite of
what option D states.
Q7: A patient with a lesion in the precentral gyrus of the left frontal lobe would most likely experience which
of the following?
Verified Answers | 100% Correct | Grade A Page 2
, BIOS 251 Anatomy & Physiology I | Exam 3 Review | Chamberlain University 2026/2027
A. Loss of somatosensory perception on the right side of the body
B. Difficulty with speech comprehension (Wernicke's area is affected)
C. Voluntary motor deficits on the contralateral (right) side of the body [CORRECT]
D. Visual field deficits in the left eye only
Correct Answer: C
Rationale: The precentral gyrus of the frontal lobe contains the primary motor cortex. The motor cortex exhibits
contralateral control, meaning the left hemisphere controls the right side of the body and vice versa. A lesion here would
cause voluntary motor weakness or paralysis on the right side (contralateral). The postcentral gyrus (parietal lobe) is the
primary somatosensory cortex. Wernicke's area is in the temporal lobe and governs speech comprehension. Visual
processing occurs in the occipital lobe.
Q8: Which brain structure serves as the major relay station for sensory and motor signals and is often referred
to as the 'gateway to the cerebral cortex'?
A. Hypothalamus
B. Epithalamus
C. Thalamus [CORRECT]
D. Subthalamus
Correct Answer: C
Rationale: The thalamus is the principal relay station for all sensory information (except olfaction) ascending to the
cerebral cortex, and it also relays motor information between the cerebellum/basal nuclei and the motor cortex. This
gateway function makes it essential for conscious perception and motor coordination. The hypothalamus regulates
homeostasis (temperature, hunger, thirst, endocrine control). The epithalamus contains the pineal gland (melatonin). The
subthalamus is involved in motor control.
Q9: Which of the following correctly pairs a cerebral lobe with its primary function?
A. Temporal lobe - primary motor control
B. Occipital lobe - visual processing [CORRECT]
C. Parietal lobe - auditory processing
D. Frontal lobe - olfactory processing
Correct Answer: B
Rationale: The occipital lobe is the primary visual processing center of the brain, containing the primary visual cortex.
The frontal lobe houses the primary motor cortex (precentral gyrus), Broca's area for speech production, and the
prefrontal cortex for executive function. The parietal lobe contains the primary somatosensory cortex (postcentral gyrus)
for touch and spatial awareness. The temporal lobe processes auditory information (primary auditory cortex), memory,
and olfactory sensations.
Q10: A patient is diagnosed with Horner's syndrome, which results from disruption of sympathetic innervation
to the head. Which of the following clinical manifestations would be expected?
A. Dilated pupil (mydriasis) on the affected side
B. Ptosis, miosis, and anhidrosis on the affected side [CORRECT]
C. Excessive sweating on the affected side of the face
D. Bilateral pupillary constriction
Correct Answer: B
Rationale: Horner's syndrome results from interruption of the sympathetic pathway to the head. It presents with the
classic triad of ptosis (drooping eyelid due to loss of superior tarsal muscle innervation), miosis (pupillary constriction due
to unopposed parasympathetic activity), and anhidrosis (decreased sweating on the affected side). Dilated pupils and
excessive sweating would indicate sympathetic hyperactivity, not disruption. The condition is typically unilateral, not
bilateral.
Verified Answers | 100% Correct | Grade A Page 3
2027)
Anatomy & Physiology I with Lab | Review Questions with Verified Answers | 100% Correct |
Grade A
Chamberlain University Curriculum Standards
Section 1: Nervous System (Questions 1-35)
Central & Peripheral Nervous System, Brain Regions, Spinal Cord, Cranial Nerves, Autonomic Nervous System,
Neurophysiology
Q1: A nursing student is studying the divisions of the nervous system. Which of the following correctly
describes the functional division that carries sensory information from receptors to the central nervous system?
A. Motor (efferent) division
B. Sensory (afferent) division [CORRECT]
C. Autonomic division only
D. Somatic motor division
Correct Answer: B
Rationale: The sensory (afferent) division transmits sensory input from peripheral receptors toward the CNS for
processing. The motor (efferent) division carries motor commands from the CNS to effectors. The autonomic and somatic
motor divisions are both subdivisions of the motor (efferent) division, not sensory pathways. This distinction between
afferent and efferent pathways is foundational to understanding neural communication in the BIOS 251 curriculum.
Q2: A patient presents with dilated pupils, increased heart rate, and bronchodilation after a stressful event.
Which division of the autonomic nervous system is primarily responsible for these 'fight-or-flight' responses?
A. Parasympathetic division
B. Sympathetic division [CORRECT]
C. Somatic motor division
D. Enteric nervous system
Correct Answer: B
Rationale: The sympathetic division of the ANS mediates the 'fight-or-flight' response, producing pupil dilation
(mydriasis), increased heart rate, bronchodilation, decreased GI motility, and glycogenolysis. It originates from the
thoracolumbar region (T1-L2) of the spinal cord. The parasympathetic division produces the opposite 'rest-and-digest'
effects. The somatic motor division controls voluntary skeletal muscle, and the enteric nervous system regulates the GI
tract independently.
Q3: Which neurotransmitter is released by postganglionic neurons in the sympathetic division at most target
organs?
A. Acetylcholine (ACh)
B. Dopamine
C. Norepinephrine (NE) [CORRECT]
,BIOS 251 Anatomy & Physiology I | Exam 3 Review | Chamberlain University 2026/2027
D. Serotonin
Correct Answer: C
Rationale: In the sympathetic division, preganglionic fibers release ACh (acting on nicotinic receptors in the ganglia),
while postganglionic fibers release norepinephrine (NE) at most target organs, acting on alpha and beta adrenergic
receptors. The exception is sweat glands, where postganglionic sympathetic fibers release ACh. Acetylcholine is the
neurotransmitter used by both pre- and postganglionic fibers in the parasympathetic division, not the sympathetic division
at target organs.
Q4: A patient has a tumor compressing the left cranial nerve III (oculomotor). Which of the following deficits
would the nurse expect to find?
A. Loss of the pupillary light reflex on the ipsilateral side [CORRECT]
B. Inability to abduct the eye laterally
C. Loss of sensation from the cornea
D. Inability to shrug the shoulder
Correct Answer: A
Rationale: Cranial nerve III (oculomotor) controls most extraocular eye movements (superior, inferior, and medial rectus;
inferior oblique), levator palpebrae superioris, and parasympathetic innervation to the sphincter pupillae muscle (pupil
constriction) and ciliary muscle (accommodation). Compression of CN III would cause ptosis, lateral deviation of the eye
(due to unopposed lateral rectus action by CN VI), and loss of the pupillary light reflex. Abduction is controlled by CN VI
(abducens), corneal sensation by CN V (trigeminal), and shoulder shrug by CN XI (accessory).
Q5: A neurologist tests a patient's patellar (knee-jerk) reflex by tapping the patellar tendon. Which type of
reflex is this, and how many synapses are involved?
A. Polysynaptic reflex involving multiple interneurons
B. Monosynaptic stretch reflex with a single synapse [CORRECT]
C. A visceral reflex mediated by the autonomic nervous system
D. A crossed-extensor reflex requiring both sides of the spinal cord
Correct Answer: B
Rationale: The patellar reflex is a monosynaptic stretch reflex. When the patellar tendon is tapped, the muscle spindles in
the quadriceps femoris are stretched, sending afferent signals via sensory neurons to the spinal cord, where they synapse
directly onto alpha motor neurons that cause the quadriceps to contract. There is only one synapse between the sensory
neuron and the motor neuron, making it monosynaptic. Polysynaptic reflexes like the withdrawal reflex involve at least
one interneuron. The crossed-extensor reflex involves coordination between both sides of the spinal cord.
Q6: Which of the following correctly describes the anatomical organization of the spinal cord?
A. Gray matter is located peripherally; white matter is centrally located
B. The spinal cord extends from the foramen magnum to the sacrum
C. Gray matter is centrally located in a butterfly shape; white matter forms peripheral tracts
[CORRECT]
D. Dorsal roots carry motor fibers; ventral roots carry sensory fibers
Correct Answer: C
Rationale: In the spinal cord, gray matter (containing neuron cell bodies) is centrally located and has a butterfly or
H-shaped appearance in cross-section. White matter (myelinated tracts) surrounds the gray matter peripherally. The spinal
cord extends from the foramen magnum to approximately the L1-L2 vertebral level, not the sacrum. Dorsal (posterior)
roots carry sensory (afferent) fibers, while ventral (anterior) roots carry motor (efferent) fibers, which is the opposite of
what option D states.
Q7: A patient with a lesion in the precentral gyrus of the left frontal lobe would most likely experience which
of the following?
Verified Answers | 100% Correct | Grade A Page 2
, BIOS 251 Anatomy & Physiology I | Exam 3 Review | Chamberlain University 2026/2027
A. Loss of somatosensory perception on the right side of the body
B. Difficulty with speech comprehension (Wernicke's area is affected)
C. Voluntary motor deficits on the contralateral (right) side of the body [CORRECT]
D. Visual field deficits in the left eye only
Correct Answer: C
Rationale: The precentral gyrus of the frontal lobe contains the primary motor cortex. The motor cortex exhibits
contralateral control, meaning the left hemisphere controls the right side of the body and vice versa. A lesion here would
cause voluntary motor weakness or paralysis on the right side (contralateral). The postcentral gyrus (parietal lobe) is the
primary somatosensory cortex. Wernicke's area is in the temporal lobe and governs speech comprehension. Visual
processing occurs in the occipital lobe.
Q8: Which brain structure serves as the major relay station for sensory and motor signals and is often referred
to as the 'gateway to the cerebral cortex'?
A. Hypothalamus
B. Epithalamus
C. Thalamus [CORRECT]
D. Subthalamus
Correct Answer: C
Rationale: The thalamus is the principal relay station for all sensory information (except olfaction) ascending to the
cerebral cortex, and it also relays motor information between the cerebellum/basal nuclei and the motor cortex. This
gateway function makes it essential for conscious perception and motor coordination. The hypothalamus regulates
homeostasis (temperature, hunger, thirst, endocrine control). The epithalamus contains the pineal gland (melatonin). The
subthalamus is involved in motor control.
Q9: Which of the following correctly pairs a cerebral lobe with its primary function?
A. Temporal lobe - primary motor control
B. Occipital lobe - visual processing [CORRECT]
C. Parietal lobe - auditory processing
D. Frontal lobe - olfactory processing
Correct Answer: B
Rationale: The occipital lobe is the primary visual processing center of the brain, containing the primary visual cortex.
The frontal lobe houses the primary motor cortex (precentral gyrus), Broca's area for speech production, and the
prefrontal cortex for executive function. The parietal lobe contains the primary somatosensory cortex (postcentral gyrus)
for touch and spatial awareness. The temporal lobe processes auditory information (primary auditory cortex), memory,
and olfactory sensations.
Q10: A patient is diagnosed with Horner's syndrome, which results from disruption of sympathetic innervation
to the head. Which of the following clinical manifestations would be expected?
A. Dilated pupil (mydriasis) on the affected side
B. Ptosis, miosis, and anhidrosis on the affected side [CORRECT]
C. Excessive sweating on the affected side of the face
D. Bilateral pupillary constriction
Correct Answer: B
Rationale: Horner's syndrome results from interruption of the sympathetic pathway to the head. It presents with the
classic triad of ptosis (drooping eyelid due to loss of superior tarsal muscle innervation), miosis (pupillary constriction due
to unopposed parasympathetic activity), and anhidrosis (decreased sweating on the affected side). Dilated pupils and
excessive sweating would indicate sympathetic hyperactivity, not disruption. The condition is typically unilateral, not
bilateral.
Verified Answers | 100% Correct | Grade A Page 3
