Spinal Cord, ETC - Chapter 13

Question 1

Which of the following is NOT found in the CNS?

neuron cell bodies located in nuclei
neuron cell bodies located in ganglia
the cerebral cortex of the brain
the gray and white matter of the spinal cord

Answer 1

neuron cell bodies located in ganglia

Think about clusters of neuron cell bodies outside the CNS.

Question 2

What is true of the peripheral nervous system (PNS)?

Spinal nerves connect to the spinal cord.
Cranial nerves connect to the brain.
Neuron cell bodies are located in ganglia.
All of the listed responses are correct.

Answer 2

All of the listed responses are correct.

Think about various characteristics of the PNS.

Question 3

What are the tracts in the CNS that link the brain with the rest of the body composed of?

nuclei and neural cortex
sensory and motor pathways
tracts and columns
None of the listed responses is correct.

Answer 3

sensory and motor pathways

What pathways are coming in and going out of the CNS?

Question 4

Which of the following statements about the spinal cord is FALSE?

It contains both sensory and motor nuclei.
It is part of the PNS.
It is associated with 31 pairs of spinal nerves.
It is approximately 18 inches in length.

Answer 4

It is part of the PNS.

Think about the division of the nervous system, which the spinal cord is part of.

Question 5

The dorsal root of a spinal nerve is the site for __________ neurons, whereas the ventral root is the site of __________ neurons.

efferent; afferent
CNS; PNS
sensory; motor
motor; sensory

Answer 5

sensory; motor

Question 6

The cervical enlargement of the spinal cord supplies nerves to the __________.

pelvis and legs
back and lumbar region
shoulder girdle and arms
thorax and abdomen

Answer 6

shoulder girdle and arms

Question 7

To withdraw cerebrospinal fluid during a spinal tap, a needle is inserted into the __________.

pia mater
subarachnoid space
epidural space
subdural space

Answer 7

subarachnoid space

Remember blood vessels are also found in this space.

Question 8

The meninx that is firmly bound to neural tissue and deep to the other meninges is the __________.

pia mater
arachnoid membrane
epidural space
dura mater

Answer 8

pia mater

Remember the first part of the name means “delicate.”

Question 9

The white matter of the spinal cord contains __________.

somatic and visceral sensory nuclei
large numbers of myelinated and unmyelinated axons
sensory and motor nuclei
cell bodies of neurons and glial cells

Answer 9

large numbers of myelinated and unmyelinated axons

Remember these structures are the pathways for action potentials.

Question 10

The area of the spinal cord that surrounds the central canal and is dominated by the cell bodies of neurons and glial cells is the __________.

white matter
descending tracts
ascending tracts
gray matter

Answer 10

gray matter

Remember this forms the shape of the letter H in the cross section of a spinal cord.

Question 11

The posterior gray horns of the spinal cord contain __________.

anterior and posterior columns
somatic and visceral motor nuclei
ascending and descending tracts
somatic and visceral sensory nuclei

Answer 11

somatic and visceral sensory nuclei

Remember this area receives information.

Question 12

The delicate connective tissue fibers that surround individual axons of spinal nerves compose a layer called the __________.

epineurium
commissures
perineurium
endoneurium

Answer 12

endoneurium

Remember the prefix that means “inner.”

Question 13

The trapezius muscle is innervated by nerves from which plexus?

sacral
lumbar
brachial
cervical

Answer 13

cervical

Think of the word that relates to the neck region.

Question 14

The brachial plexus innervates the __________.

neck and arm
thorax and arm
shoulder girdle and arm
neck and shoulder girdle

Answer 14

shoulder girdle and arm

Remember the meaning of the term “brachial” as well as what connects to this.

Question 15

Parallel processing is the “neural circuit” in which __________.

several neurons synapse on the postsynaptic neuron
several neurons or neuronal pools process the same information at one time
a specific input is broadly distributed
use of positive feedback stimulates presynaptic neurons

Answer 15

several neurons or neuronal pools process the same information at one time

Remember what the word “parallel” means.

Question 16

When sensory information is relayed from one part of the brain to another, the pattern is called __________.

reverberation
convergence
serial processing
parallel processing

Answer 16

serial processing

Question 17

The final step involved in a neural reflex is __________.

information processing
the activation of a motor neuron
the activation of a sensory neuron
a response by an effector

Answer 17

a response by an effector

Remember the purpose and eventual result of a reflex.

Question 18

The goal of information processing during a neural reflex is the selection of __________.

an appropriate motor response and the activation of specific motor neurons
appropriate sensory selections and activation of specific sensory neurons
appropriate motor selections and specific sensory responses
appropriate sensory selections and specific motor responses

Answer 18

an appropriate motor response and the activation of specific motor neurons

Remember the result of reflex actions and the decisions involved.

Question 19

Consider the steps of a reflex arc. Which step follows information processing?

response of a peripheral effector
arrival of a stimulus and activation of a receptor
activation of a motor neuron
activation of a sensory neuron

Answer 19

activation of a motor neuron

Question 20

Which of the following statements about innate reflexes is FALSE?

They are genetically programmed.
They are the result of connections formed between neurons during development.
They are exemplified by the suckling reflex.
They are learned over time and enhanced by repetition.

Answer 20

They are learned over time and enhanced by repetition.

Remember these reflexes are present at birth.

Question 21

A professional skier making a rapid, automatic adjustment in body position while racing is performing an example of __________.

an innate reflex
an acquired reflex
a patellar reflex
a cranial reflex

Answer 21

an acquired reflex

Remember this reflex requires learning.

Question 22

Which of the following reflexes occurs in the LEAST amount of time?

knee-jerk reflex
tendon reflex
crossed extensor reflex
reflexes associated with walking

Answer 22

knee-jerk reflex

Remember this is a monosynaptic reflex.

Question 23

The sensory receptors in the stretch reflex are the __________.

Golgi tendon organs
Meissner

’

s corpuscles
Pacinian corpuscles
muscle spindles

Answer 23

muscle spindles

Remember these are in deep structures.

Question 24

When one set of motor neurons is stimulated, those controlling antagonistic muscles are inhibited. This statement illustrates the principle of __________.

crossed extensor reflex
ipsilateral reflex
reciprocal inhibition
contralateral reflex

Answer 24

reciprocal inhibition

Think about the equal and opposite actions happening at the same time in this system.

Question 25

Which of the following statements concerning postural reflexes is INCORRECT?

Postural reflexes are triggered by extremely sensitive stretch receptors.
Postural reflexes help maintain an upright posture.
Postural reflexes may be monosynaptic or polysynaptic.
None of the listed responses is incorrect; all are correct

Answer 25

None of the listed responses is incorrect; all are correct.

Think about all the statements that are correct.

Question 26

Which of the following occurs as descending inhibitory synapses develop?

noticeable fanning of the toes in adults
disappearance of the Babinski response
a decrease in the facilitation of spinal reflexes
a positive Babinski response

Answer 26

disappearance of the Babinski response

Remember this involves a reflex present in infants.

Question 27

The highest level of motor control involves a series of interactions that occur __________.

in the gamma efferents to the intrafusal fibers
as monosynaptic reflexes that are rapid but stereotyped
in the descending pathways that provide facilitation and inhibition
in centers in the brain that can modulate or build on reflexive motor patterns

Answer 27

in centers in the brain that can modulate or build on reflexive motor patterns

Remember this occurs in the most superior regions of the CNS.

Question 28

The designation C3 relative to the spinal cord refers to the __________.

third cerebrospinal layer
third coccygeal ligament
third cranial nerve
third cervical segment

Answer 28

third cervical segment

Question 29

April stubs her left hallux as she is walking to the kitchen at night. Which nerve and which plexus are involved in the sensation of pain sent to her brain?

fibular nerve and sacral plexus
tibial nerve and sacral plexus
median nerve and brachial plexus
sciatic nerve and lumbar plexus

Answer 29

fibular nerve and sacral plexus

Question 30

Spinal nerves are classified as mixed nerves because they contain __________.

ascending and descending pathways
white matter and gray matter
both sensory and motor fibers
both dorsal and ventral roots

Answer 30

both sensory and motor fibers

Question 31

Which of the following statements about the meninges is FALSE?

The pia mater is firmly bound to the neural tissue of the spinal cord and brain.
CSF can be found in the subarachnoid space.
The denticulate ligaments branch from the pia layer to stabilize the position of the spinal cord.
An epidural block is a dose of anesthetic given in the subdural space.

Answer 31

An epidural block is a dose of anesthetic given in the subdural space.

Remember to look at prefixes to distinguish meanings.

Question 32

The cauda equina is a complex of the spinal cord that includes __________.

the coccygeal and denticulate ligaments
the enlargements of the cervical and thoracic regions of the cord
the posterior and anterior median sulci
the filum terminale and the ventral and dorsal roots caudal to the conus medullaris

Answer 32

the filum terminale and the ventral and dorsal roots caudal to the conus medullar is

Remember this name means “horse’s tail.”

Question 33

The epidural space is an area that contains __________.

a delicate network of collagen and elastic fibers
the spinal fluid
loose connective tissue, blood vessels, and adipose tissue
blood vessels and sensory and motor fibers

Answer 33

loose connective tissue, blood vessels, and adipose tissue

Remember this is a superficial region around the spinal cord.

Question 34

In the spinal cord, the cerebrospinal fluid is found within the __________.

central canal and subarachnoid space
central canal and epidural space
subarachnoid and epidural spaces
subdural and epidural spaces

Answer 34

central canal and subarachnoid space

Remember the axial region as well as the space containing networks of connective tissue fibers.

Question 35

Which of the following statements about shingles is FALSE?

A person who has had chickenpox could get shingles.
It is an inflammation of spinal nerves and their corresponding dermatomes.
It is caused by the varicella zoster virus.
Fortunately, shingles, like chickenpox, can be experienced once in life

Answer 35

Fortunately, shingles, like chickenpox, can be experienced only once in life.

Question 36

The dura mater attaches itself at its base to the skeletal system through what structure?

coccygeal ligament
dorsal roots of spinal nerves
denticulate ligament
None of the listed responses is correct.

Answer 36

coccygeal ligament

Question 37

The axons in the white matter of the spinal cord that carry sensory information up toward the brain are organized into __________.

posterior white columns
anterior white columns
ascending tracts
descending tracts

Answer 37

ascending tracts

Remember the word referring to moving in an upward direction

Question 38

In reference to the vertebral column, C2 refers to the cervical nerve that __________.

follows vertebra C2
precedes vertebra C2
precedes vertebra C3
is between vertebrae C2 and C3

Answer 38

precedes vertebra C2

Remember that this pattern follows all cervical vertebrae except one.

Question 39

The white ramus is the branch of a spinal nerve that consists of __________.

myelinated postganglionic axons
myelinated preganglionic axons
unmyelinated preganglionic axons
unmyelinated postganglionic axons

Answer 39

myelinated preganglionic axons

Remember the effect of myelin as well as where signals travel away from the CNS.

Question 40

Unmyelinated fibers that innervate glands and smooth muscles in the body wall or limbs form the __________.

ramus communicans
gray ramus
autonomic ganglion
white ramus

Answer 40

gray ramus

Remember the effect of myelin on the appearance of the fibers.

Question 41

The lumbo-sacral plexus that supplies the pelvic girdle and the leg includes the spinal nerves __________.

L4–S4
T12–S4
T12–L4
T1–T12

Answer 41

T12–S4

Think about the region just above the lumbar area.

Question 42

Pain receptors are the __________.

dendrites of sensory neurons
specialized cells that respond to a limited range of stimuli
activators of motor neurons
axons of motor neurons

Answer 42

dendrites of sensory neurons

Remember these are unmodified entryways to the neural cell body.

Question 43

Reflexive removal of a hand from a hot stove and blinking when the eyelashes are touched are examples of __________.

cranial reflexes
innate reflexes
synaptic reflexes
acquired reflexes

Answer 43

innate reflexes

Remember no learning is required for these reflexes.

Question 44

Why are the most complicated responses produced by polysynaptic responses?

The delay between stimulus and response is minimized.
The interneurons can control several different muscle groups.
There is an absence of interneurons, which minimizes delay.
The postsynaptic motor neuron serves as the processing center.

Answer 44

The interneurons can control several different muscle groups.

Remember that more association networks increase complexity.

Question 45

Several neurons synapsing on a single postsynaptic neuron are __________.

convergence
serial processing
divergence
reverberation

Answer 45

convergence

Question 46

The activity occurring in the Golgi tendon organ involves __________.

excitatory or inhibitory postsynaptic potentials
a cooperative effort by many different muscle groups
the stretching of the collagen fibers and stimulation of the sensory neuron
many complex polysynaptic reflexes

Answer 46

the stretching of the collagen fibers and stimulation of the sensory neuron

Remember this functions to protect the muscle fibers from damage.

Question 47

Which of the following is an example of a visceral reflex?

stretch reflex
micturition (urinary) reflex
withdrawal reflex
crossed extensor reflex

Answer 47

micturition (urinary) reflex

Remember the definition for internal organ.

Question 48

Which of the following is an example of a somatic reflex?

micturition (urination) reflex
defecation reflex
stretch reflex
Hering-Breuer reflex (lung inflation reflex)

Answer 48

stretch reflex

Remember this involves organs under volitional control.

Question 49

In an adult, CNS injury is suspected if there is __________.

a negative Babinski reflex
a plantar reflex
a positive Babinski reflex
an increase in facilitating synapses

Answer 49

a positive Babinski reflex

Remember what should only be present in infants.

Question 50

Which of these INCORRECTLY explains a sequence of events in a muscle spindle under the given conditions?

central portion of the intrafusal fibers is stretched; frequency of action potentials increases
gamma efferents are stimulated; triggers contraction of myofibrils of intrafusal fibers
frequency of action potentials are decreased; triggers contraction of extrafusal fibers
central portion of the intrafusal fibers is compressed; frequency of action potentials decreases

Answer 50

frequency of action potentials are decreased; triggers contraction of extrafusal fibers

Remember stimulation will produce action potentials along sensory pathways.