Deck 12: Spinal Cord and Spinal Nerves

Question 1

During a spinal tap, cerebrospinal fluid is obtained from which of the following locations?

A) Dural sinus
B) Epidural space
C) Subarachnoid space
D) Subdural space
E) Sagittal sinus

Answer 1

C

Question 2

There are ________ enlargements of the spinal cord where nerves supplying the extremities enter and leave.

A) two
B) three
C) four
D) five
E) six

Answer 2

A

Question 3

Which of the following statements concerning structures of the spinal cord is false?

A) The dorsal root of the spinal cord conveys sensory (afferent) nerve impulses to the spinal cord.
B) The posterior horn of the cord contains the cell bodies of motor neurons.
C) The ventral root is formed by the axons of neurons in the lateral and anterior horns.
D) The dorsal and ventral roots unite to form spinal nerves.
E) The ventral root of the spinal cord conveys motor (efferent) nerve impulses away from the spinal cord.

Answer 3

B

Question 4

Where is cerebrospinal fluid found around the spinal cord?

A) Subdural space
B) Epidural space
C) Thecal sac
D) Subarachnoid space

Question 5

The conus medullaris

A) anchors the spinal cord to the coccyx.
B) is a tapered, cone like region immediately inferior to the lumbar enlargement.
C) marks the exit of nerves to the upper extremity.
D) is located adjacent to the foramen magnum.
E) is inferior to the cauda equina.

Question 6

The spinal cord

A) controls the reticular activating system.
B) stores reflexive memory.
C) forms memory engrams.
D) links the peripheral nervous system to the brain.
E) is characterized by conscious activity.

Question 7

The cross-sectional view of the spinal cord reveals white matter on the

A) inside, gray matter on the outside, and a dorsal motor root.
B) outside, gray matter on the inside, and a ventral motor root.
C) inside, gray matter on the outside, and a dorsal sensory root.
D) outside, gray matter on the inside, and a ventral sensory root.

Question 8

Which structure anchors the thecal sac and conus medullaris to the coccyx?

A) Filum terminale
B) Denticulate ligaments
C) Pia mater
D) Cauda equina

Question 9

The spinal cord ends at the ________.

A) sacrum
B) coccyx
C) 5th lumbar vertebrae
D) 2nd lumbar vertebrae

Question 10

The spinal cord begins at the ________.

A) cerebellum
B) medulla oblongata
C) foramen magnum
D) conus medullaris
E) 1st cervical vertebrae

Question 11

The sac surrounding the spinal cord is the ________.

A) dural sac
B) meningeal sac
C) thecal sac
D) epidural sac

Question 12

What is found in the dorsal root ganglion?

A) The cell bodies of multipolar motor neurons
B) The cell bodies of pseudo-unipolar sensory neurons
C) The cell bodies of multipolar interneurons
D) The cell bodies of bipolar sensory neurons

Question 13

The thickest of the meninges is the ________.

A) pia mater
B) arachnoid mater
C) subdural space
D) subarachnoid space
E) dura mater

Question 14

In the spinal cord, white matter is organized into

A) horns and the gray matter into columns.
B) horns and the gray matter into roots.
C) columns and the gray matter into horns.
D) columns and the gray matter into tracts.

Question 15

Which structure makes the dorsal root different from the ventral root?

A) The dorsal root has a ganglion.
B) The dorsal root has a tract.
C) The dorsal root has a nucleus.
D) The dorsal root appears the same as the ventral root.

Question 16

The middle, thin, spider-like meninx is the ________.

A) dura mater
B) pia mater
C) ecto mater
D) arachnoid mater

Question 17

What space, found between the vertebral wall and the dura mater, is the area for injecting anesthesia for childbirth?

A) Subarachnoid space
B) Subdural space
C) Epidural space
D) Epipial space

Question 18

The ventral root of a spinal nerve contains ________.

A) only sensory fibers
B) only motor fibers
C) only afferent fibers
D) both sensory and motor fibers
E) a ganglion

Question 19

The sensory root of a spinal nerve is also referred to as ________ root.

A) anterior
B) dorsal
C) efferent
D) ventral
E) lateral

Question 20

The motor root of a spinal nerve is also referred to as the ________ root.

A) afferent
B) dorsal
C) posterior
D) ventral
E) sensory

Question 21

Sam is curling very heavy weights and suddenly drops them. Which reflex forced this action by Sam to prevent tendon damage?

A) Muscle spindle reflex
B) Golgi tendon reflex
C) Gamma motor reflex
D) Withdrawal reflex
E) Alpha motor neuron reflex

Question 22

Which portion of a reflex arc is most likely to be located entirely within the central nervous system?

A) Sensory neuron
B) Motor neuron
C) Effector
D) Interneuron
E) Sensory receptor

Question 23

Muscles and glands that are capable of producing a response when stimulated by motor neurons are called ________.

A) aponeuroses
B) effectors
C) neuromodulators
D) receptors
E) sensory organs

Question 24

Reflexes function in

A) removing the body from painful stimuli.
B) keeping the body from falling.
C) maintaining blood pressure.
D) maintaining blood CO₂ levels.
E) All of the choices are correct.

Question 25

Which of the following events in a stretch reflex occurs last?

A) Alpha motor neurons transmit action potentials to muscle causing contraction.
B) Muscle spindle detects stretch of muscle.
C) Afferent neurons conduct action potentials to the spinal cord.
D) Afferent neurons synapse with alpha motor neurons.
E) Muscle is stretched.

Question 26

Structurally, the simplest reflex is the ________.

A) stretch reflex
B) Golgi tendon reflex
C) reciprocal reflex
D) alternating reflex
E) withdrawal reflex

Question 27

The sensory receptor of the stretch reflex is the ________.

A) Golgi tendon organ
B) muscle spindle
C) dorsal root ganglion
D) collateral axon
E) alpha motor neurons

Question 28

Reflexes

A) are homeostatic.
B) are not homeostatic.
C) are voluntary conscious responses to a stimulus.
D) are integrated in the spinal cord, but not the brain.
E) are integrated in the brain, but not the spinal cord.

Question 29

The knee-jerk reflex involves which of the following?

A) Sensory and motor neurons
B) Sensory neuron, interneuron, and motor neuron
C) Sensory neuron, motor neuron, and inhibitory interneurons
D) Sensory neuron and interneuron
E) The brain

Question 30

Muscle spindles

A) are innervated by gamma motor neurons.
B) originate in the spinal cord.
C) are specialized nerve cells.
D) are found encapsulated in nerve endings.
E) are innervated by alpha motor neurons.

Question 31

Place the following parts of a reflex arc in the correct order beginning with the sensory receptor.
(1) Motor neuron
(2) Interneuron
(3) Effector
(4) Sensory neuron
(5) Sensory receptor

A) 5, 1, 2, 3, 4
B) 5, 3, 2, 4, 1
C) 5, 4, 3, 2, 1
D) 5, 2, 3, 4, 1
E) 5, 4, 2, 1, 3

Question 32

The muscles of the back contract to straighten so that you sit at a more erect posture and subsequently the muscles are suddenly stretched as you nod off. Which of the following best represents the sequence of events when you start to nod off?
(1) Muscles of the back are stretched.
(2) The muscle spindle is stretched.
(3) Action potentials in sensory neurons of the muscle spindles increase.
(4) Action potentials in alpha motor neurons of skeletal muscle fibers increase.
(5) Skeletal muscle of the back contract.

A) 1, 2, 3, 4, 5
B) 1, 5, 2, 3, 4
C) 1, 5, 3, 2, 4
D) 5, 2, 3, 4, 1
E) 4, 5, 3, 2, 1

Question 33

Gamma motor neurons

A) are located in tendons.
B) transmit action potentials to skeletal muscle.
C) regulate the sensitivity of the muscle spindle.
D) enable the brain to perceive that a muscle has been stretched.
E) innervate the whole muscle.

Question 34

Stimulation of the Golgi tendon organs result in which of the following changes in the reflex arc?

A) Stimulation of a stimulatory interneuron
B) Stimulation of an inhibitory neuron
C) Decreased action potentials in alpha motor neurons
D) Contraction of skeletal muscle fibers
E) Both "stimulation of an inhibitory neuron" and "decreased action potentials in alpha motor neurons" are correct.

Question 35

Doctor Johansson wants to test a patient's reflexes by briskly striking the patellar tendon with a reflex hammer. Which reflex is Dr. Johansson testing?

A) Golgi tendon reflex
B) Withdrawal reflex
C) Knee-jerk reflex
D) Crossed extensor reflex
E) Reciprocal innervation

Question 36

A reflex that protects limbs by removing them from painful stimuli is the ________ reflex.

A) stretch
B) crossed extensor
C) Golgi tendon
D) alternating
E) withdrawal

Question 37

Stretch reflexes

A) are learned voluntary responses.
B) aid in maintaining proper posture.
C) prevent muscles from being damaged by excessive tension.
D) cause the removal of limbs from painful stimuli.
E) prevent falling.

Question 38

What is found in the lateral gray horns of the spinal cord?

A) The cell bodies of somatic motor neurons
B) The cell bodies of sensory neurons
C) The cell bodies of autonomic motor neurons
D) The cell bodies of somatic sensory neurons

Question 39

Reflex arcs

A) are capable of receiving a stimulus and yielding a response.
B) are the basic structural units of the nervous system.
C) occur primarily in the cerebral cortex of the brain.
D) involve inhibitory neurons.
E) do not involve the spinal cord.

Question 40

The reflex that prevents excessive tension in a muscle is the ________ reflex.

A) stretch
B) withdrawal
C) Golgi tendon
D) reciprocal
E) crossed extensor

Question 41

Intercostal nerves are formed from the

A) thoracic plexus.
B) ventral rami of thoracic spinal nerves.
C) dorsal rami of thoracic spinal nerves.
D) rami communicans of the thoracic spinal nerves.
E) cervical plexus.

Question 42

Because the stretch reflexes can be traced back along certain spinal nerve routes,

A) they are not used in diagnosis of brain potential brain damage.
B) they are only useful for diagnosis if there has been damage to the spinal cord.
C) they are helpful when determining at what level of the spinal cord damage may have occurred.
D) they are only helpful when diagnosing problems in the extremities.
E) they are only helpful if the patient is conscious.

Question 43

Reciprocal innervation

A) is associated with the Golgi tendon reflex.
B) stimulates antagonistic muscles.
C) results in reduced resistance to the reflex.
D) reinforces the withdrawal reflex.
E) inhibits the stretch reflex.

Question 44

The brachial plexus supplies nerves that function to contract which of the following?

A) The diaphragm
B) Intercostal muscles
C) Muscles of the arm and forearm
D) Muscles of the lower limb
E) Abdominal muscles

Question 45

Damage to which of these nerves would be most life-threatening?

A) Median nerves
B) Phrenic nerves
C) Lumbar nerves
D) Sciatic nerves
E) Radial nerves

Question 46

A collapsed intervertebral foramen could affect all of the following spinal nerves EXCEPT ________.

A) C2-C8
B) T1-T12
C) L1-L5
D) C1

Question 47

There are ________ cervical spinal nerves.

A) eight
B) twelve
C) six
D) five
E) fourteen

Question 48

The endoneurium

A) surrounds nerve cell bodies.
B) surrounds individual axons and their Schwann cells.
C) bundles axons into fascicles.
D) bundles fascicles into nerves.
E) surrounds nerve tracts in the spinal cord.

Question 49

The epineurium

A) surrounds nerve cell bodies.
B) surrounds individual axons and their Schwann cells.
C) bundles axons into fascicles.
D) bundles fascicles into nerves.
E) bundles fascicles into axons.

Question 50

A man was in an accident during which his spinal cord was severed between C6 and C7. Which of the following would NOT be a consequence of this injury?

A) Loss of sensation in the trunk below the shoulders, the lower limbs, and portions of the arms
B) Loss of use of the phrenic nerves and paralysis of the diaphragm
C) Loss of movement in the lower limbs
D) Loss of the use of the intercostals nerves, and breathing would be affected because the intercostals muscles would be paralyzed
E) Loss of touch sensation on the lower lumbar region.

Question 51

The cutaneous sensory distribution of a spinal nerve can be mapped as a ________.

A) dermatome
B) plexitome
C) microtome
D) myotome
E) superdome

Question 52

Which of the following statements concerning the structure of spinal nerves is true?

A) The ventral root contains motor or efferent fibers.
B) The ventral root has a prominent root ganglion.
C) Rootlets from the surface of the spinal cord form the dorsal and ventral rami.
D) Each spinal nerve is formed by the union of a cranial nerve and a spinal nerve.
E) Spinal nerves do not have specific cutaneous distributions.

Question 53

Ventral rami of some spinal nerves join with each other to form a ________.

A) ganglion
B) dermatome
C) cord
D) plexus
E) nerve

Question 54

Initiating the withdrawal reflex in both legs at the same time would cause one to

A) maintain posture longer.
B) fall.
C) decrease muscle tension.
D) develop resistance in one limb and reduce resistance in the other.
E) hop.

Question 55

Dermatomal maps are important clinically because they

A) can be used to check for motor function.
B) locate the position of cranial nerves.
C) can be used to help locate nerve damage.
D) indicate what muscles are innervated by each spinal nerve.
E) can be used to detect cranial nerve damage.

Question 56

Which of the following combinations indicates the correct distribution of spinal nerve pairs?

A) 7 cervical - 12 thoracic - 6 lumbar - 5 sacral - 1 coccygeal
B) 7 cervical - 12 thoracic - 5 lumbar - 6 sacral - 1 coccygeal
C) 8 cervical - 12 thoracic - 6 lumbar - 4 sacral - 1 coccygeal
D) 8 cervical - 12 thoracic - 5 lumbar - 5 sacral - 1 coccygeal
E) 7 cervical - 13 thoracic - 6 lumbar - 5 sacral - 1 coccygeal

Question 57

The adaptive significance of the crossed extensor reflex when a person steps on a tack is to

A) remove the foot from the tack.
B) increase the rate at which withdrawal of the limb occurs.
C) slow the rate of removal of the foot from the tack.
D) reduce the pain sensations.
E) prevent the person from falling down.

Question 58

The branch of a spinal nerve that innervates deep muscles on the dorsal thorax is the ________.

A) ramus communicans
B) lateral ramus
C) dorsal ramus
D) ventral ramus
E) medial ramus

Question 59

If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of ________.

A) sensation
B) movement
C) sensation and movement
D) pain
E) None of the choices are correct.

Question 60

The perineurium

A) surrounds nerve cell bodies.
B) surrounds individual axons and their Schwann cells.
C) bundles axons into fascicles.
D) bundles fascicles into nerves.
E) bundles fascicles into axons.

Question 61

Which nerve is involved when a dancer points his/her toes?

A) Tibial
B) Femoral
C) Obturator
D) Pudendal
E) Common fibular (peroneal)

Question 62

Label component "A" of the reflex arc.

A) Sensory receptor
B) Effector organ
C) Sensory neuron
D) Motor neuron
E) Interneuron

Question 63

When a person sits on a hard surface for a period of time, his foot or leg may "go to sleep." This sensation is the result of compressing the ________ nerve.

A) femoral
B) sciatic
C) obturator
D) pudendal
E) ulnar

Question 64

Using the biceps brachii to flex the forearm requires innervation by the ________ nerve.

A) radial
B) musculocutaneous
C) ulnar
D) median
E) axillary

Question 65

When a person hits their "funny bone," they cause temporary damage to the ________ nerve.

A) axillary
B) radial
C) musculocutaneous
D) ulnar
E) median

Question 66

If a person fell down the steps and then developed pain down his anterior thigh into the knee, which of the following spinal nerves was probably damaged?

A) Obturator
B) Femoral
C) Tibial
D) Common fibular (peroneal)
E) Pudendal

Question 67

Damage to the phrenic nerve would result in

A) the loss of motor activity in the arms.
B) an increased heart rate.
C) an inability to swallow.
D) difficulty breathing.
E) a decreased heart rate.

Question 68

Which of the following nerves is part of the brachial plexus?

A) Peroneal
B) Ansa cervicalis
C) Sciatic
D) Musculocutaneous
E) Femoral

Question 69

The gastrocnemius muscle is most likely to be innervated by the ________ nerve.

A) obturator
B) common fibular (peroneal)
C) tibial
D) femoral
E) median

Question 70

When someone taps you on your shoulder, they stimulate the ________ nerve.

A) axillary
B) brachial
C) radial
D) musculocutaneous
E) ulnar

Question 71

The sciatic nerve is composed of the

A) femoral nerve and the tibial nerve.
B) tibial nerve and the common fibular nerve.
C) femoral nerve and the obturator nerve.
D) common fibular nerve and the pudendal nerve.
E) superior gluteal and inferior gluteal.

Question 72

Branches of the ________ nerve are anesthetized before a doctor performs an episiotomy for childbirth.

A) genitofemoral
B) gluteal
C) cutaneous femoral
D) pudendal
E) common fibular (peroneal)

Question 73

Spinal nerves C5-T1 make up the ________ plexus.

A) sacral
B) lumbar
C) brachial
D) cervical
E) radial

Question 74

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

A) lumbar
B) femoral
C) sacral
D) pelvic
E) brachial

Question 75

Which of the following nerves is associated with the lumbosacral plexus?

A) Phrenic
B) Median
C) Musculocutaneous
D) Ulnar
E) Obturator

Question 76

Adduction of the thigh involves the ________ nerve.

A) peroneal
B) femoral
C) obturator
D) pudendal
E) tibial

Question 77

Which of the following nerves is a branch of both the cervical plexus and the brachial plexus?

A) Axillary
B) Femoral
C) Phrenic
D) Sciatic
E) Splanchnic

Question 78

Improper use of crutches could cause compression of the ________ nerve.

A) axillary
B) radial
C) musculocutaneous
D) ulnar
E) median

Question 79

An injury to the wrist that results in edema in the carpal tunnel would compress the ________ nerve.

A) axillary
B) radial
C) musculocutaneous
D) ulnar
E) median

Question 80

If you pinch your index finger in a door, pain sensations are carried via the ________ nerve.

A) radial
B) median
C) axillary
D) musculocutaneous
E) ulnar