BIO 201 Exam 4 V3 | BIO 201 A&P |
StraighterLine | Q&A with Rationale (BIO
201 Exam 4)
1. Which region of the brain is primarily responsible for coordinating voluntary muscle
movements and maintaining posture and balance?
A. Cerebrum
B. Thalamus
C. Medulla oblongata
D. Cerebellum
Answer: D
Rationale: The cerebellum is located posterior to the brainstem and is vital for motor
control. It processes input from the motor cortex and sensory receptors to provide precise
timing for skeletal muscle contraction. Damage to this area often results in ataxia or a loss
of coordination.
2. Which cranial nerve is unique because it travels into the thoracic and abdominal cavities to
provide parasympathetic innervation to visceral organs?
A. Facial (VII)
B. Glossopharyngeal (IX)
C. Accessory (XI)
,D. Vagus (X)
Answer: D
Rationale: The Vagus nerve, or Cranial Nerve X, is known as the ‘wandering’ nerve because
of its extensive distribution. it carries about 90 percent of all parasympathetic fibers in the
body. This nerve is critical for regulating heart rate, breathing, and digestive system
activity.
3. What is the primary function of the blood-brain barrier (BBB)?
A. To prevent all substances from entering the brain
B. To provide a physical cushion for the cerebral cortex
C. To selectively regulate the passage of substances between the blood and the CNS
D. To produce cerebrospinal fluid for the ventricles
Answer: C
Rationale: The blood-brain barrier is a highly selective semipermeable border that
protects the brain from harmful substances. It is formed by tight junctions between
endothelial cells and the foot processes of astrocytes. While it allows nutrients like glucose
to pass, it blocks many toxins and drugs from entering brain tissue.
4. Which division of the autonomic nervous system is responsible for the ‘rest and digest’
response?
A. Somatic nervous system
, B. Sympathetic division
C. Parasympathetic division
D. Central nervous system
Answer: C
Rationale: The parasympathetic division aims to conserve energy and maintain body
functions at rest. It promotes activities like digestion, defecation, and diuresis while
slowing the heart rate. This system works in opposition to the sympathetic nervous system
to maintain homeostasis.
5. The primary somatosensory cortex is located in which specific fold of the cerebrum?
A. Precentral gyrus
B. Superior temporal gyrus
C. Postcentral gyrus
D. Corpus callosum
Answer: C
Rationale: The postcentral gyrus is located in the parietal lobe just posterior to the central
sulcus. It is the site where the brain receives and processes sensory information such as
touch and proprioception. This area is organized into a sensory homunculus representing
different body parts.
StraighterLine | Q&A with Rationale (BIO
201 Exam 4)
1. Which region of the brain is primarily responsible for coordinating voluntary muscle
movements and maintaining posture and balance?
A. Cerebrum
B. Thalamus
C. Medulla oblongata
D. Cerebellum
Answer: D
Rationale: The cerebellum is located posterior to the brainstem and is vital for motor
control. It processes input from the motor cortex and sensory receptors to provide precise
timing for skeletal muscle contraction. Damage to this area often results in ataxia or a loss
of coordination.
2. Which cranial nerve is unique because it travels into the thoracic and abdominal cavities to
provide parasympathetic innervation to visceral organs?
A. Facial (VII)
B. Glossopharyngeal (IX)
C. Accessory (XI)
,D. Vagus (X)
Answer: D
Rationale: The Vagus nerve, or Cranial Nerve X, is known as the ‘wandering’ nerve because
of its extensive distribution. it carries about 90 percent of all parasympathetic fibers in the
body. This nerve is critical for regulating heart rate, breathing, and digestive system
activity.
3. What is the primary function of the blood-brain barrier (BBB)?
A. To prevent all substances from entering the brain
B. To provide a physical cushion for the cerebral cortex
C. To selectively regulate the passage of substances between the blood and the CNS
D. To produce cerebrospinal fluid for the ventricles
Answer: C
Rationale: The blood-brain barrier is a highly selective semipermeable border that
protects the brain from harmful substances. It is formed by tight junctions between
endothelial cells and the foot processes of astrocytes. While it allows nutrients like glucose
to pass, it blocks many toxins and drugs from entering brain tissue.
4. Which division of the autonomic nervous system is responsible for the ‘rest and digest’
response?
A. Somatic nervous system
, B. Sympathetic division
C. Parasympathetic division
D. Central nervous system
Answer: C
Rationale: The parasympathetic division aims to conserve energy and maintain body
functions at rest. It promotes activities like digestion, defecation, and diuresis while
slowing the heart rate. This system works in opposition to the sympathetic nervous system
to maintain homeostasis.
5. The primary somatosensory cortex is located in which specific fold of the cerebrum?
A. Precentral gyrus
B. Superior temporal gyrus
C. Postcentral gyrus
D. Corpus callosum
Answer: C
Rationale: The postcentral gyrus is located in the parietal lobe just posterior to the central
sulcus. It is the site where the brain receives and processes sensory information such as
touch and proprioception. This area is organized into a sensory homunculus representing
different body parts.
