BIO 201- Exam 4 -Dr. Larson ASU
(2026/2027) Latest 2026/2027 Exam
Questions And Correct Detailed Answers
1. Define "rostral."
A) Toward the tail
B) Toward the nose
C) Toward the back
D) Toward the stomach
Answer: B) Toward the nose
Rationale: In humans, "rostral" means toward the forehead; in animals, it means toward
the nose/beak.
2. Define "caudal."
A) Toward the nose
B) Toward the tail
C) Toward the head
D) Toward the front
Answer: B) Toward the tail
Rationale: "Caudal" refers to the direction toward the tail. In humans, this is roughly
equivalent to "toward the spinal cord".
3. Define "cortex."
A) Deeper masses of gray matter
B) Bundles of myelinated axons
C) Surface layer of gray matter
D) The inner core of the brain
,Answer: C) Surface layer of gray matter
Rationale: The cortex is the outer layer of gray matter covering the cerebrum and
cerebellum.
4. Define "nuclei" in the context of the CNS.
A) Bundles of axons
B) Surface layer of gray matter
C) Deeper masses of gray matter
D) The fluid-filled spaces of the brain
Answer: C) Deeper masses of gray matter
Rationale: In the CNS, nuclei are collections of neuron cell bodies (gray matter) located
deep within the brain, distinct from the cortical surface layer.
5. Define "tracts."
A) Surface layer of gray matter
B) Deeper masses of gray matter
C) Bundles of myelinated axons (white matter)
D) The membranes covering the brain
Answer: C) Bundles of myelinated axons (white matter)
Rationale: Tracts are bundles of myelinated axons that form the white matter of the CNS
and connect different parts of the brain.
6. Compare the volume of the cerebrum to the cerebellum.
A) The cerebellum is about 83% of brain volume; the cerebrum contains over half of all
neurons
B) The cerebrum is about 83% of brain volume; the cerebellum contains over half of all
neurons
C) The cerebrum and cerebellum are equal in volume
D) The cerebellum is larger in volume
,Answer: B) The cerebrum is about 83% of brain volume; the cerebellum contains
over half of all neurons
Rationale: The cerebrum accounts for approximately 83% of total brain volume, while
the cerebellum contains more than half of all neurons despite its smaller size.
7. The longitudinal fissure separates:
A) The frontal and parietal lobes
B) The two cerebral hemispheres
C) The cerebrum and cerebellum
D) The temporal and occipital lobes
Answer: B) The two cerebral hemispheres
Rationale: The longitudinal fissure is the deep groove that separates the left and right
cerebral hemispheres.
8. The central sulcus separates which lobes?
A) The frontal and temporal lobes
B) The parietal and occipital lobes
C) The frontal and parietal lobes
D) The temporal and occipital lobes
Answer: C) The frontal and parietal lobes
Rationale: The central sulcus is the prominent groove that separates the frontal lobe
from the parietal lobe.
9. Define "gyri."
A) Shallow grooves of the brain
B) Deep grooves of the brain
C) Thick folds (hills) of the brain
D) The connections between hemispheres
Answer: C) Thick folds (hills) of the brain
, Rationale: Gyri are the elevated ridges or folds on the surface of the cerebral cortex.
10. Define "sulci."
A) Thick folds (hills) of the brain
B) Shallow grooves (valleys) of the brain
C) Deep grooves of the brain
D) The connections between hemispheres
Answer: B) Shallow grooves (valleys) of the brain
Rationale: Sulci are the shallow grooves or valleys between the gyri on the brain's
surface.
11. The corpus callosum connects:
A) The cerebral hemispheres
B) The cerebrum and cerebellum
C) The brain and spinal cord
D) The thalamus and hypothalamus
Answer: A) The cerebral hemispheres
Rationale: The corpus callosum is a thick nerve bundle at the bottom of the longitudinal
fissure that connects the two cerebral hemispheres, allowing communication between
them.
12. Gray matter consists of:
A) Bundles of axons
B) Neuron cell bodies, dendrites, and synapses
C) Myelinated nerve fibers
D) Neuroglial cells only
Answer: B) Neuron cell bodies, dendrites, and synapses
(2026/2027) Latest 2026/2027 Exam
Questions And Correct Detailed Answers
1. Define "rostral."
A) Toward the tail
B) Toward the nose
C) Toward the back
D) Toward the stomach
Answer: B) Toward the nose
Rationale: In humans, "rostral" means toward the forehead; in animals, it means toward
the nose/beak.
2. Define "caudal."
A) Toward the nose
B) Toward the tail
C) Toward the head
D) Toward the front
Answer: B) Toward the tail
Rationale: "Caudal" refers to the direction toward the tail. In humans, this is roughly
equivalent to "toward the spinal cord".
3. Define "cortex."
A) Deeper masses of gray matter
B) Bundles of myelinated axons
C) Surface layer of gray matter
D) The inner core of the brain
,Answer: C) Surface layer of gray matter
Rationale: The cortex is the outer layer of gray matter covering the cerebrum and
cerebellum.
4. Define "nuclei" in the context of the CNS.
A) Bundles of axons
B) Surface layer of gray matter
C) Deeper masses of gray matter
D) The fluid-filled spaces of the brain
Answer: C) Deeper masses of gray matter
Rationale: In the CNS, nuclei are collections of neuron cell bodies (gray matter) located
deep within the brain, distinct from the cortical surface layer.
5. Define "tracts."
A) Surface layer of gray matter
B) Deeper masses of gray matter
C) Bundles of myelinated axons (white matter)
D) The membranes covering the brain
Answer: C) Bundles of myelinated axons (white matter)
Rationale: Tracts are bundles of myelinated axons that form the white matter of the CNS
and connect different parts of the brain.
6. Compare the volume of the cerebrum to the cerebellum.
A) The cerebellum is about 83% of brain volume; the cerebrum contains over half of all
neurons
B) The cerebrum is about 83% of brain volume; the cerebellum contains over half of all
neurons
C) The cerebrum and cerebellum are equal in volume
D) The cerebellum is larger in volume
,Answer: B) The cerebrum is about 83% of brain volume; the cerebellum contains
over half of all neurons
Rationale: The cerebrum accounts for approximately 83% of total brain volume, while
the cerebellum contains more than half of all neurons despite its smaller size.
7. The longitudinal fissure separates:
A) The frontal and parietal lobes
B) The two cerebral hemispheres
C) The cerebrum and cerebellum
D) The temporal and occipital lobes
Answer: B) The two cerebral hemispheres
Rationale: The longitudinal fissure is the deep groove that separates the left and right
cerebral hemispheres.
8. The central sulcus separates which lobes?
A) The frontal and temporal lobes
B) The parietal and occipital lobes
C) The frontal and parietal lobes
D) The temporal and occipital lobes
Answer: C) The frontal and parietal lobes
Rationale: The central sulcus is the prominent groove that separates the frontal lobe
from the parietal lobe.
9. Define "gyri."
A) Shallow grooves of the brain
B) Deep grooves of the brain
C) Thick folds (hills) of the brain
D) The connections between hemispheres
Answer: C) Thick folds (hills) of the brain
, Rationale: Gyri are the elevated ridges or folds on the surface of the cerebral cortex.
10. Define "sulci."
A) Thick folds (hills) of the brain
B) Shallow grooves (valleys) of the brain
C) Deep grooves of the brain
D) The connections between hemispheres
Answer: B) Shallow grooves (valleys) of the brain
Rationale: Sulci are the shallow grooves or valleys between the gyri on the brain's
surface.
11. The corpus callosum connects:
A) The cerebral hemispheres
B) The cerebrum and cerebellum
C) The brain and spinal cord
D) The thalamus and hypothalamus
Answer: A) The cerebral hemispheres
Rationale: The corpus callosum is a thick nerve bundle at the bottom of the longitudinal
fissure that connects the two cerebral hemispheres, allowing communication between
them.
12. Gray matter consists of:
A) Bundles of axons
B) Neuron cell bodies, dendrites, and synapses
C) Myelinated nerve fibers
D) Neuroglial cells only
Answer: B) Neuron cell bodies, dendrites, and synapses
