Ch. 13 The Peripheral Nervous System & Reflex Activity - Test Practice Questions

Spinal nerves exiting the cord from the level of L4 to S4 form the ________.

sacral plexus

The cranial nerve with a dual origin (brain and spinal cord) is the ________.

accessory

Which of the following is not an example of an exteroceptor?

A) pressure

B) temperature

C) pain

D) touch

E) baroreceptor

E

Inborn or intristic reflexes are ________.

A) always mediated by the brain

B) rapid, predictable, learned responses

C) involuntary, yet may be modified by learned behavior

D) autonomic only

C

Transduction refers to conversion of ________.

A) receptor energy to stimulus energy

B) stimulus information to nerve impulses

C) afferent impulses to efferent impulses

D) presynaptic nerve impulses to postsynaptic nerve impulses

B

Problems in balance may follow trauma to which nerve?

vestibulocochlear

Feeling a gentle caress on your arm would likely involve all of the following except ________.

A) hair follicle receptors

B) tactile discs

C) Meissner's corpuscles

D) Pacinian corpuscles

D

If the ventral root of a spinal nerve were cut, what would be the result in the tissue or region that nerve supplies?

A) a complete loss of sensation and movement

B) loss of neither sensation nor movement but only of autonomic control

C) complete loss of sensation

D) a complete loss of voluntary movement

D

Striking the "funny bone" is actually stimulation of (or injury to) the ________.

ulnar nerve

Starting at the spinal cord, the subdivisions of the brachial plexus are (in order):

roots, trunks, divisions, and cords

Select the correct definition.

A) Magnitude estimation is the simplest level of sensation.

B) Perceptual detection is the ability to detect how much stimulus is applied to the body.

C) Spatial discrimination allows us to recognize textures.

D) Pattern recognition allows us to see a familiar face.

D

The trochlear nerve conveys proprioceptor impulses from the ________ to the brain.

superior rectus muscle

The cranial nerves that have neural connections with the tongue include all except the ________.

A) glossopharyngeal

B) trochlear

C) trigeminal

D) facial

B

Irritation of a major nerve of this plexus may cause hiccups.

cervical plexus

Which receptors adapt most slowly?

nociceptors

Nerves that carry impulses toward the CNS only are ________.

afferent nerves

A fracture of the ethmoid bone could result in damage to which cranial nerve?

olfactory

Which of the following nerves does not arise from the brachial plexus?

A) radial

B) phrenic

C) ulnar

D) median

B

A reflex that causes muscle relaxation and lengthening in response to muscle tension is called a

Golgi tendon reflex

The sciatic nerve is a combination of which two nerves?

A) common fibular and tibial

B) posterior femoral cutaneous and tibial

C) pudendal and common fibular

D) pudendal and posterior femoral cutaneous

A

Mixed cranial nerves containing both motor and sensory fibers include all except which of the following?

A) facial

B) trigeminal

C) oculomotor

D) olfactory

D

The flexor muscles in the anterior arm (biceps brachii and brachialis) are innervated by what nerve?

musculocutaneous

Potentially damaging stimuli that result in pain are selectively detected by ________.

nociceptors

Pressure, pain, and temperature receptors in the skin are ________.

interorceptors

Select the statement that is most correct.

A) The dorsal root ganglion is a motor-only structure.

B) Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons.

C) Ganglia are collections of neuron cell bodies in the spinal cord that are associated with efferent fibers.

D) The cell bodies of afferent ganglia are located in the spinal cord.

B

Regeneration within the CNS ________.

A) is more successful than with the PNS

B) is promoted by growth inhibitors and glial scars

C) typically allows axonal sprouting of 20 mm

D) is prevented due to growth-inhibiting proteins of oligodendrocytes

D

A patient who received a blow to the side of the skull exhibits the following signs and symptoms on that side of the face: he is unable to close his eye, and the corner of his mouth droops. Which cranial nerve has been damaged?

facial

The abducens nerve ________.

A) supplies innervation to the lateral rectus muscle of the eye

B) exits from the medulla

C) if paralyzed, exhibits Bell's palsy

D) relays sensory information from taste buds on the tongue

A

The ________ nerve is not a branch of the trigeminal nerve.

A) mandibular

B) ophthalmic

C) maxillary

D) cervical

D

After axonal injury, regeneration in peripheral nerves is guided by ________

Schwann cells

In a crossed-extensor reflex, if the right arm was grabbed it would flex and the left arm would

extend

Which of the following is not a main level of neural integration in the somatosensory system?

A) circuit

B) perceptual

C) segmental

D) receptor

C

All processing at the circuit level going up to the perceptual level must synapse in the ________.

thalamus

Which of the following is not an aspect of sensory perception?

A) feature attraction

B) pattern recognition

C) spatial discrimination

D) quality estimation

E) magnitude estimation

D

A fall or an improperly delivered gluteal injection could result in ________.

sciatica

The posterior side of the thigh, leg, and foot is served by the ________ nerve.

tibial

Which of the following is the correct simple spinal reflex arc?

A) effector, efferent neuron, integration center, afferent neuron, receptor

B) receptor, afferent neuron, integration center, efferent neuron, effector

C) receptor, efferent neuron, integration center, afferent neuron, effector

D) effector, afferent neuron, integration center, efferent neuron, receptor

B

The patellar "knee jerk" reflex is an example of a(n) ________.

stretch reflex

A major nerve of the lumbar plexus is the ________.

femoral

Which of the following is an incorrect statement regarding the occurrence of a sensation?

A) The stimulus energy must be converted into the energy of a graded potential called a transduction potential.

B) The stimulus energy must match the specificity of the receptor.

C) A generator potential in the associated sensory neuron must reach threshold.

D) The stimulus energy must occur within the receptor's receptive field.

A

Bell's palsy is characterized by ________.

paralysis of facial muscles

The facial nerve is cranial nerve number ________.

VII

The ________ nerve is the largest of the cranial nerves.

trigeminal

The perineurium defines the boundary of a ________.

fascicle

A pebble kicked up into a shoe causes the ________ of localized deep pressure, but the ________ of it is an awareness of discomfort.

sensation; perception

________ is the tingling sensation or numbness when blood has been cut off from an area, as when the foot "goes to sleep."

Ischemia

What is Wallerian degeneration?

The complete degeneration of the distal end of an axon after it has been severed.

Information regarding skeletal muscle tension is provided by ________ and muscle length by ________.

Golgi tendon organs; muscle spindles

Complex motor behavior such as walking depends on ________ patterns.

fixed-action

________ is a protective reflex that also overrides the spinal pathways and prevents any other reflexes from using them at the same time.

flexor reflex

Which receptors are modified free-nerve endings found in the deeper levels of the epidermis?

tactile discs

Ventral spinal cord roots contain ________ fibers, while the dorsal roots contain ________ fibers.

motor (efferent); sensory (afferent)

Pain, temperature, and coarse touch are involved in the ________ ascending pathways of the somatosensory system.

nonspecific

T/F

The meningeal branch of a spinal nerve actually reenters the vertebral canal to innervate the meninges and blood vessels.

True

T/F

Dermatomes are skin segments that relate to sensory innervation regions of the spinal nerves.

True

T/F

The musculocutaneous nerve is a major nerve of the brachial plexus.

True

T/F

External strabismus and ptosis could be caused by damage to the oculomotor nerve.

True

T/F

The dorsal ramus consists only of motor fibers bringing information to the spinal cord.

False

Dorsal and ventral rami are similar because they both contain what?

sensory and motor fibers

T/F

The cerebellum and basal nuclei are involved in regulating motor activity, starting and stopping movements, and coordinating postural movements.

True

T/F

There are 41 pairs of spinal nerves.

False, there are 31 pairs.

T/F

The only cranial nerves to extend beyond the head and neck region are the vagus nerves.

True

T/F

The obturator nerve branches from the sacral plexus.

False

T/F

The glossopharyngeal nerve is the only cranial nerve that contains sensory fibers.

False

T/F

The second cranial nerve forms a chiasma at the base of the brain for partial crossover of neural fibers.

True

T/F

In the somatosensory system there are no third-order neurons in the cerebellum.

True

T/F

Reciprocal inhibition means that while one sensory nerve is stimulated, another sensory neuron for synergistic muscles in the same area is inhibited and cannot respond.

False

T/F

Irritation of the phrenic nerve may cause diaphragm spasms called hiccups.

True

The cranial nerve that helps to regulate blood pressure and digestion.

vagus nerve

Controls the outputs of the cortex and regulates motor activity.

Precommand level

Trauma to a nerve of this plexus may cause wrist drop.

Brachial plexus

Tests both upper and lower motor pathways. The sole of the foot is stimulated with a dull instrument.

plantar

Produces muscle relaxation and lengthening in response to tension; the contracting muscle relaxes as its antagonist is activated.

Golgi tendon

Produces a rapid withdrawal of the body part from a painful stimulus; ipsilateral.

Flexor

Intermediate relay for incoming and outgoing neurons.

Projection level

A fall or improper administration of an injection to the buttocks may injure a nerve of this plexus.

Sacral plexus

Striking the "funny bone" (ulnar nerve) may cause injury to a nerve of this plexus.

Brachial plexus

The neural machinery of the spinal cord, including spinal cord circuits.

Segmental level

The cerebellum and basal nuclei.

Precommand level

Central pattern generators.

Segmental level

The obturator and femoral nerves branch from this plexus.

Lumbar plexus

Consists of an ipsilateral withdrawal reflex and a contralateral extensor reflex; importantin maintaining balance.

Crossed-extensor

Serves the senses of hearing and equilibrium.

Vestibulocochlear

Formed by the union of a cranial and a spinal root.

Accessory

The phrenic nerve branches from this plexus.

Cervical plexus

Receptors located in epithelium of the nasal cavity.

Olfactory

Includes cortical and brain stem motor areas.

Projection level

Prevents muscle overstretching and maintains muscle tone.

Stretch