Chapter 13 Central Nervous System
What are the masses of gray matter deep inside each cerebral hemisphere?
cerebral nuclei
Within each intervertebral foramen, an anterior root and its corresponding posterior root unite to form a
spinal nerve
A familiar type of monosynaptic reflex that monitors and regulates the length of skeletal muscle is the
stretch reflex
The central white matter consists of which three groups of axons?
association, commissural, and projection tracts
Myelinated axons that extend between the cerebral hemispheres are called
commissural fibers
What is the thick tract between the cerebral hemispheres?
corpus callosum
Which brain structure is described as basal ganglia involved in motor activities and is related to Huntington's Disease?
corpus striatum
The cortex of cerebellum is part of (gray/white) matter
gray
The red nucleus is part of (gray/white) matter
gray
Which brain region has a crossover of fibers of pyramidal tracts?
medulla oblongata
What brain region contains the cerebral aquaduct?
midbrain
What brain structure houses the substantia nigra and red nucleus?
midbrain
Which cerebral lobe is located immediately posterior to the central sulcus and superior to the lateral sulcus?
parietal lobe
If a reflex arc involves a single interneuron, it is classified as
polysynaptic
Which statement does not describe the parietal lobe? A) is involved with general sensory functions B) contains the functionally important precentral gyrus C) is bounded posteriorly by the parieto-occipital sulcus D) forms the superoposterior part of each cerebral hemisphere
B
The tapered inferior end of the spinal cord is called the
conus medullaris
Within the cauda equina is a thin strand of pia mater called the
filum terminale
The tetrahedron-shaped cavity between the pons and cerebellum is the
fourth ventricle
White matter of the spinal cord is partitioned into ____________, each containing both ascending and descending ____________.
funiculi; tracts
The white matter of the spinal cord is composed primarily of
myelinated axons
Which structure provides motor innervation to the deep back muscles and receives sensory information from the skin of the back?
posterior ramus
Cell bodies of sensory neurons are housed in each
posterior root ganglion
The primary motor cortex is located in which cerebral structure?
precentral gyrus
Which cerebral cortical area coordinates learned, skilled motor activities?
premotor cortex
Which cortical region is responsible for the conscious awareness of touch, pressure, pain, and temperature?
primary somatosensory cortex
What brain structures are involved in visual and auditory reflexes?
superior and inferior colliculi
The visual reflex center is housed within the
superior colliculus
All inputs to cerebral cortex must first synapse in what part of the brain structure?
thalamus's nuclei
The roots of the brachial plexus are actually
the anterior rami of spinal nerves
If a patient suffers damage to her postcentral gyrus in her right cerebral hemisphere, which side of her body feels no sensation?
the left side of her body
Which cranial nerve innervates the muscles of mastication and provides sensory information from the face, mouth, and anterior scalp?
trigeminal
Which cranial nerve plays the largest role in the autonomic control of visceral functions?
vagus
The ____________ nerve monitors sensations of balance and equilibrium as well as hearing.
vestibulocochlear
The word root vagus, as in "vagus nerve," most nearly means
wandering
Internal capsule and corona radiata are part of (gray/white) matter
white
Pyramids are part of (gray/white) matter
white
The cerebellar peduncle is part of (gray/white) matter
white
The medial lemniscus is part of (gray/white) matter
white
The anterior funiculi are interconnected by the
white commissure
The outer region of the spinal cord, composed primarily of myelinated axons, is called the
white matter
What are the 4 functions of cerebrospinal fluid?
- buoyancy for the brain - cushions neural structures from sudden movements - delivers nutrients - removes waste products
What are the 3 functions of the hypothalamus?
- controls endocrine system - regulates sleep-wake cycle - controls autonomic nervous system
Which branches of spinal nerves innervate the limbs and the anterolateral portions of the trunk? A) rami communicantes B) anterior rami C) posterior rami D) all of the above
B) anterior rami
Which description of the cerebellum is incorrect? A) has a complex, convoluted surface covered by cerebellar cortex B) a narrow band of cortex called the vermis lies along the midline C) has prominent folds called gyri covering the left and right hemispheres D) internally, white matter called the arbor vitae forms branching patterns
C
Which of the following statements is false about the choroid plexus? A) It is located within the ventricles of the brain. B) It is composed of ependymal cells and capillaries. C) It forms the blood-brain barrier. D) It produces and circulates cerebrospinal fluid.
C
Which structure contains motor axons only? A) posterior root ganglion B) posterior root C) anterior root D) anterior gray horn
C
Which term describes the specific region of skin monitored by a single spinal nerve? A) ramus communicans B) posterior ramus C) dermatome D) anterior ramus
C. dermatome
Of the following, which nerve ranges farthest from its roots in the cervical plexus and is most vital to your health? A) supraclavicular B) ansa cervicalis C) phrenic D) lesser occipital
C. phrenic
The subarachnoid space contains ________, and the epidural space contains ________.
CSF; fat, CT and blood vessels
From the subarachnoid space, excess cerebrospinal fluid flows into the dural venous sinuses through the
arachnoid villi
Which adjective best describes reflex responses? A) variable B) automatic C) deliberate D) voluntary
automatic
The anterior root of a spinal nerve contains
axons of motor neurons only
Cranial nerves with purely sensory functions include which of the following? A) olfactory, optic, and vestibulocochlear B) trigeminal and facial C) glossopharyngeal, accessory, and hypoglossal D) all of the above
A
Which spinal cord components contain cell bodies of interneurons and axons of sensory neurons? A) posterior horns B) lateral horns C) anterior horns D) all of the above
A) posterior horns
Components of the limbic system A) conduct and process olfactory sensations B) collectively process and experience emotions C) are essential in storing memories and forming long-term memory D) all of the above
D
Which of the following is not generally involved in a reflex? A) conduction of a nerve impulse to the CNS by a sensory neuron B) information processing by interneurons in an integration center C) transmission of a nerve impulse to a peripheral effector organ D) inhibition of an effector by a stimulus from a motor neuron
D
In regions where the two layers of the dura mater separate, the gap between them is called
a dural venous sinus
The first step involved in a typical neural reflex is
activation of a receptor by a stimulus
The meningeal layer immediately deep to the subdural space is called the
arachnoid
The posterior and anterior roots of the ____________ must elongate because the spinal cord stops growing before the vertebral column does.
cauda equina
What is the collective name for all of the axons that project inferiorly from the spinal cord?
cauda equina
The lateral horns found in the T1-L2 regions of the spinal cord contain
cell bodies of autonomic motor neurons
Which structures would not be found in the anterior horns of the spinal cord? A) motor nuclei B) cell bodies of somatic motor neurons C) cell bodies of autonomic motor neurons D) glial cells
cell bodies of autonomic motor neurons
Coordinating skeletal muscle movements and maintaining equilibrium are two of several important functions of the
cerebellum
The subdivision of the brain that does not initiate somatic motor movements, but rather coordinates and fine-tunes those movements is the
cerebellum
What brain structure's surface is folded into folia and coordinates movements?
cerebellum
The substance that fills the subarachnoid space is
cerebrospinal fluid
The four major regions of the brain are the
cerebrum, diencephalon, brainstem, and cerebellum
Branches of which plexuses innervate anterior neck muscles, the skin of the neck, and parts of the head and shoulders?
cervical
The four principal nerve plexuses are the
cervical, brachial, lumbar, and sacral
What structure produces cerebrospinal fluid in each ventricle?
choroid plexus
The blood-brain barrier of the CNS is missing or markedly reduced in what 3 structures?
choroid plexus, hypothalamus, and pineal gland
The tough, protective ____________ extends between adjacent vertebrae to fuse with the connective tissue surrounding the spinal nerves.
dura mater
Which sequence lists the cranial meninges in order from superficial to deep?
dura mater, arachnoid mater, pia mater
The spinal cord meninges, in order from the outermost to the innermost, are the
dura mater, arachnoid, and pia mater
Between the dura mater and the inner walls of the vertebrae is the
epidural space
Although extending from the end of the spinal cord, the ____________ contains no neural fibers, only fibrous connective tissue.
filum terminale
In the spinal cord, a ____________ is to a tract as a horn is to a nucleus.
funiculus
Cranial nerve nuclei are part of (gray/white) matter
gray
Axons cross from one side of the spinal cord to the other through a gray matter region called the
gray commissure
Hormones released by the posterior pituitary are actually produced by the ____________, which also controls the activities of the anterior pituitary as well as numerous autonomic functions, emotions, drives, and natural rhythms.
hypothalamus
What brain structure has control of temperature, autonomic nervous system, hunger, and water balance?
hypothalamus
What brain structure is part of diencephalon with vital centers controlling heart rate, some aspects of emotion, and blood pressure?
hypothalamus
Which region of the diencephalon controls the ANS and endocrine system, body temperature, circadian rhythms, and various emotions and behavioral drives?
hypothalamus
Reflexive turning of the head and eyes in the direction of a sound is controlled by the ____________ of the mesencephalon.
inferior colliculi
The anterior rami of spinal nerves T1-T11 are called...?
intercostal nerves
Corpus callosum is to commissural as ____________ is to projection tracts.
internal capsule
If its receptor and effector are on the same side of the body, a reflex arc is termed ____________; if on opposite sides, it is ____________.
ipsilateral; contralateral
Which thalamic nuclei relay visual information from the optic tract to the visual cortex and mesencephalon?
lateral geniculate nuclei
Because of its major roles in controlling emotions, drives, and memory, damage to the ____________ could drastically alter an individual's personality.
limbic system
The cerebral hemispheres are separated by the
longitudinal fissure
What does the destruction of the ventral horn cells of the spinal cord result in?
loss of motor control
Which body regions are innervated by the lumbar enlargement of the spinal cord?
lower limbs
Nerves from the brachial plexuses innervate the
pectoral girdles and upper limbs
Which structure contains some autonomic centers involved in regulating respiration?
pons
Which two parts of the brain most directly control normal breathing?
pons and medulla oblongata