480
UNIT 3
Regulation and Integration of the Body
2.
Te gray matter of the spinal cord forms from the alar and basal
plates. Fiber tracts form the outer white matter. Te neural crest
forms the sensory (dorsal root) ganglia.
3.
Maternal and environmental factors may impair embryonic brain
development, and oxygen deprivation destroys brain cells. Severe
congenital brain disorders include cerebral palsy, anencephaly,
hydrocephalus, and spina bifida.
4.
Premature babies have trouble regulating body temperature because
the hypothalamus is one of the last brain areas to mature prenatally.
5.
Development of motor control indicates progressive myelination
and maturation of a child’s nervous system.
6.
Brain growth ends in young adulthood. Neurons die throughout
life and most are not replaced; brain weight and volume decline
with age.
7.
Healthy elders maintain nearly optimal intellectual function.
Disease—particularly cardiovascular disease—is the major cause
of declining mental function with age.
10.
Poliomyelitis results from inflammation and destruction of the
ventral horn neurons by the poliovirus. Paralysis and muscle
atrophy ensue.
11.
Amyotrophic lateral sclerosis (ALS) results from destruction of
the ventral horn neurons and the pyramidal tracts. Te victim
eventually loses the ability to swallow, speak, and breathe. Death
generally occurs within five years.
Diagnostic Procedures for Assessing CNS
Dysfunction
(pp. 474–475)
1.
Diagnostic procedures used to assess neurological condition
and function range from routine reflex testing to sophisticated
techniques such as cerebral angiography, C± scans, MRI scans,
and PE± scans.
Developmental Aspects of the Central Nervous
System
(pp. 475–477)
1.
Te CNS develops from the embryonic neural tube—the brain
from the rostral part and the spinal cord from the caudal part.
Multiple Choice/Matching
(Some questions have more than one correct answer. Select the best
answer or answers from the choices given.)
1.
Te primary motor cortex, Broca’s area, and the premotor cortex
are located in which lobe?
(a)
frontal,
(b)
parietal,
(c)
temporal,
(d)
occipital.
2.
Te innermost layer of the meninges, delicate and closely
apposed to the brain tissue, is the
(a)
dura mater,
(b)
corpus
callosum,
(c)
arachnoid mater,
(d)
pia mater.
3.
Cerebrospinal fluid is formed by
(a)
arachnoid villi,
(b)
dura
mater,
(c)
choroid plexuses,
(d)
all of these.
4.
A patient has suffered a cerebral hemorrhage that has caused
dysfunction of the precentral gyrus of his right cerebral cortex.
As a result,
(a)
he cannot voluntarily move his le² arm or leg,
(b)
he feels no sensation on the le² side of his body,
(c)
he feels
no sensation on his right side.
5.
Choose the correct term from the key to respond to the
statements describing various brain areas.
Key:
(a)
cerebellum
(b)
corpora quadrigemina
(c)
corpus callosum
6.
Which of the following tracts convey vibration and other
specific sensations that can be precisely localized?
(a)
pyramidal
tract,
(b)
medial lemniscus,
(c)
lateral spinothalamic tract,
(d)
reticulospinal tract.
7.
Destruction of the ventral horn cells of the spinal cord results
in loss of
(a)
integrating impulses,
(b)
sensory impulses,
(c)
voluntary motor impulses,
(d)
all of these.
8.
Fiber tracts that allow neurons within the same cerebral
hemisphere to communicate are
(a)
association fibers,
(b)
commissures,
(c)
projection fibers.
9.
A number of brain structures are listed below. If an area is
primarily gray matter, write
a
in the answer blank; if mostly white
matter, respond with
b
.
____ (1)
cerebral cortex
____ (2)
corpus callosum and corona radiata
____ (3)
red nucleus
____ (4)
medial and lateral nuclear groups
____ (5)
medial lemniscus
____ (6)
cranial nerve nuclei
____ (7)
spinothalamic tract
____ (8)
fornix
____ (9)
cingulate and precentral gyri
10.
A professor unexpectedly blew a loud horn in his anatomy and
physiology class. Te students looked up, startled. Te reflexive
movements of their eyes were mediated by the
(a)
cerebral cortex,
(b)
inferior olives,
(c)
raphe nuclei,
(d)
superior colliculi,
(e)
nucleus gracilis.
11.
Identify the stage of sleep described by using choices from the
key. (Note that responses a–d refer to NREM sleep.)
Key:
(a)
stage 1
(b)
stage 2
(c)
stage 3
(d)
stage 4
(e)
REM
____ (1)
the stage when blood pressure and heart rate reach
their lowest levels
____ (2)
indicated by movement of the eyes under the lids;
dreaming occurs
____ (3)
when nightmares are likely to occur
____ (4)
when the sleeper is very easily awakened; EEG shows
alpha waves
Review Questions
12
(d)
striatum
(e)
hypothalamus
(f)
medulla
(g)
midbrain
(h)
pons
(i)
thalamus
____ (1)
basal nuclei involved in fine control of motor activities
____ (2)
region where there is a gross crossover of fibers of
descending pyramidal tracts
____ (3)
control of temperature, autonomic nervous system
reflexes, hunger, and water balance
____ (4)
houses the substantia nigra and cerebral aqueduct
____ (5)
relay stations for visual and auditory stimuli input;
found in midbrain
____ (6)
houses vital centers for control of the heart, respiration,
and blood pressure
____ (7)
brain area through which all the sensory input is
relayed to get to the cerebral cortex
____ (8)
brain area most concerned with equilibrium, body
posture, and coordination of motor activity
previous page 514 Human Anatomy and Physiology (9th ed ) 2012 read online next page 516 Human Anatomy and Physiology (9th ed ) 2012 read online Home Toggle text on/off