Deck 12: The Spinal Cord, Spinal Nerves, and Spinal Reflexes

Question 1

Which of the following associations is incorrect?

A) 8 cervical spinal nerves
B) 11 thoracic spinal nerves
C) 5 lumbar spinal nerves
D) 5 sacral spinal nerves
E) 1 coccygeal spinal nerve

Answer 1

B

Question 2

Enlargements of the spinal cord occur

A) near the posterior median sulcus.
B) adjacent to the anterior median fissure.
C) in those spinal segments that control the limbs.
D) in the thoracic region.
E) in the sacral region.

Answer 2

C

Question 3

In an adult, the conus medullaris is found at about

A) T₆.
B) T₁₀.
C) L₁.
D) L₅.
E) Co₁.

Answer 3

C

Question 4

Compared to the vertebral column, the spinal cord is

A) longer.
B) shorter.
C) the same length.

Question 5

Cerebrospinal fluid flows within the

A) filum terminale.
B) subarachnoid space.
C) dura mater.
D) pia mater.
E) arachnoid mater.

Question 6

The spinal cord consists of five regions and ________ segments.

A) 5
B) 12
C) 25
D) 31
E) number varies widely among individuals

Question 7

After age ________ the vertebral column continues to elongate, but the spinal cord itself does not.

A) 8
B) 12
C) 18
D) 4
E) none of the above

Question 8

The layer of the meninges in direct contact with the spinal cord is the

A) dura mater.
B) subarachnoid space.
C) arachnoid.
D) pia mater.
E) choroid plexus.

Question 9

The tough, fibrous, outermost covering of the spinal cord is the

A) arachnoid.
B) pia mater.
C) dura mater.
D) epidural block.
E) periosteum.

Question 10

Blood vessels that supply the spinal cord branch within the

A) spinal meninges.
B) spinal nerve.
C) white matter.
D) spinal columns.
E) gray matter.

Question 11

The epidural space contains

A) cerebrospinal fluid.
B) lymph.
C) blood.
D) connective tissue and blood vessels.
E) denticulate ligaments.

Question 12

Samples of CSF for diagnostic purposes are normally obtained by placing the tip of a needle in the

A) dura mater.
B) arachnoid mater.
C) epidural space.
D) subarachnoid space.
E) cerebral ventricles.

Question 13

The subdural space lies between

A) the arachnoid mater and the pia mater.
B) the pia mater and the dura mater.
C) the dura mater and the arachnoid mater.
D) the pia mater and the subarachnoid space.
E) the endosteum and the periosteum.

Question 14

The ________ is a strand of fibrous tissue that provides longitudinal support as a component of the coccygeal ligament.

A) conus medullaris
B) filum terminale
C) cauda equina
D) dorsal root
E) ventral root

Question 15

Axons crossing from one side of the spinal cord to the other within the gray matter are found in the

A) anterior gray horns.
B) lateral gray horns.
C) posterior gray horns.
D) gray commissures.
E) white commissures.

Question 16

The specialized membranes that surround the spinal cord are termed the

A) cranial meninges.
B) cranial mater.
C) spinal meninges.
D) spinal mater.
E) epidural membranes.

Question 17

The dorsal root ganglia mainly contain

A) axons of motor neurons.
B) axons of sensory neurons.
C) cell bodies of motor neurons.
D) cell bodies of sensory neurons.
E) synapses.

Question 18

The spinal cord continues to elongate until about age

A) 20 years.
B) 10 years.
C) 4 years.
D) 6 months.
E) 2 months.

Question 19

Spinal nerves are

A) purely sensory.
B) purely motor.
C) both sensory and motor.
D) interneuronal.
E) involuntary.

Question 20

The outward projections from the central gray matter of the spinal cord are called

A) wings.
B) horns.
C) pyramids.
D) fibers.
E) tracts.

Question 21

Figure 12-1 The Spinal Cord
Use Figure 12-1 to answer the following questions:
Identify the structure labeled "10."

A) anterior white commissure
B) anterior median fissure
C) anterior white column
D) anterior gray commissure
E) anterior white horn

Question 22

The posterior horns of the spinal cord contain mainly

A) sensory nuclei.
B) somatic motor nuclei.
C) autonomic motor nuclei.
D) nerve tracts.
E) sympathetic nuclei.

Question 23

In the condition ________, a virus infects dorsal root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes.

A) myasthenia gravis
B) neuronal damage
C) shingles
D) chickenpox
E) Hodgkin's disease

Question 24

The anterior horns of the spinal cord contain mainly

A) sensory nuclei.
B) somatic motor nuclei.
C) autonomic motor nuclei.
D) nerve tracts.
E) sympathetic nuclei.

Question 25

What is the function of the structure labeled "12"?

A) control of skeletal muscle
B) somatic sensory receiving
C) visceral sensory receiving
D) control of visceral effectors
E) ascending pathway

Question 26

Mary is in an automobile accident and suffers a spinal cord injury. She has lost feeling in her lower body. Her doctor tells her that swelling is compressing a portion of her spinal cord. Which part of her cord is likely to be compressed?

A) the anterior gray horns
B) the anterior gray commissures
C) ascending tracts
D) descending tracts
E) the anterior white commissures

Question 27

Nerve tracts or fasciculi make up the

A) central canal.
B) posterior gray horns.
C) gray commissures.
D) anterior white columns.
E) all of the above

Question 28

Figure 12-1 The Spinal Cord
Use Figure 12-1 to answer the following questions:
Identify the structure labeled " 1."

A) anterior white column
B) lateral white column
C) lateral white horn
D) median commissure
E) posterior white column

Question 29

In the spinal cord, white matter is separated into ascending and descending tracts organized as

A) nuclei.
B) ganglia.
C) columns.
D) nerves.
E) horns.

Question 30

The outermost connective-tissue covering of nerves is the

A) endoneurium.
B) endomysium.
C) perineurium.
D) epineurium.
E) epimysium.

Question 31

The gray horns of the spinal cord contain mainly

A) nerve tracts.
B) columns.
C) meninges.
D) nerve cell bodies.
E) funiculi.

Question 32

What is the function of the structure labeled "14"?

A) control of skeletal muscle
B) somatic sensory processing
C) control of visceral effectors
D) somatic motor control
E) visceral sensory processing

Question 33

The layer of connective tissue that surrounds individual axons within a peripheral nerve is termed the

A) endoneurium.
B) perineurium.
C) aponeurium.
D) metaneurium.
E) subneurium.

Question 34

The white matter of the spinal cord is mainly

A) unmyelinated axons.
B) neuroglia.
C) Schwann cells.
D) myelinated axons.
E) nodes of Ranvier.

Question 35

The layer of connective tissue that surrounds a fascicle within a peripheral nerve is the

A) perineurium.
B) epineurium.
C) endoneurium.
D) epimysium.
E) endosteum.

Question 36

Spinal nerves from the sacral region of the cord innervate the ________ muscles.

A) shoulder
B) intercostal
C) abdominal
D) leg
E) facial

Question 37

Where do somatic motor neurons reside?

A) 10
B) 12
C) 13
D) 14
E) 15

Question 38

The white matter of the spinal cord contains

A) bundles of axons with common origins, destinations, and functions.
B) bundles of dendrites with common origins, destinations, and functions.
C) sensory and motor nuclei.
D) both axons and dendrites.
E) interneurons.

Question 39

A viral disease that destroys the cells of the anterior gray horn will

A) lead to muscle weakness or paralysis.
B) interfere with position sense.
C) mainly interfere with crude touch and temperature sense.
D) block autonomic regulation.
E) all of the above

Question 40

Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect?

A) loss of sensation in his torso
B) inability to breathe
C) problems with moving his arms
D) uncontrollable sweating of his feet
E) problems with moving his legs

Question 41

Figure 12-2 Spinal Nerves
Use Figure 12-2 to answer the following questions:
Identify the structure labeled "2."

A) ventral root
B) dorsal ramus
C) spinal nerve
D) ventral ramus
E) white ramus

Question 42

Sensory input from interoceptors of visceral organs are carried to the spinal nerve via the ________.

A) dorsal rami
B) ventral rami
C) anterior horn
D) gray rami
E) sympathetic nerves

Question 43

The ________ innervates the ventrolateral body surface, structures in the body wall, and the limbs.

A) white rami communicantes
B) gray rami communicantes
C) dorsal ramus
D) ventral ramus
E) dermatomes

Question 44

The dorsal root of a spinal nerve contains

A) axons of motor neurons.
B) axons of sensory neurons.
C) cell bodies of motor neurons.
D) cell bodies of sensory neurons.
E) interneurons.

Question 45

The ventral root of a spinal nerve contains

A) axons of motor neurons.
B) axons of sensory neurons.
C) cell bodies of motor neurons.
D) cell bodies of sensory neurons.
E) interneurons.

Question 46

In which structure are sensory cell bodies located?

A) 4
B) 6
C) 5
D) 10
E) 12

Question 47

The postganglionic fibers that connect an sympathetic ganglion and carry fibers that innervate glands and smooth muscle of the body wall or limbs are the

A) white rami communicantes.
B) gray rami communicantes.
C) dorsal ramus.
D) ventral ramus.
E) dermatomes.

Question 48

Each peripheral nerve provides ________ innervation to peripheral structures.

A) motor
B) sensory
C) motor AND sensory
D) motor OR sensory
E) motor AND/OR sensory

Question 49

Figure 12-2 Spinal Nerves
Use Figure 12-2 to answer the following questions:
Identify the structure labeled "8."

A) peripheral nerve
B) dorsal ramus
C) spinal nerve
D) ventral root
E) dorsal root

Question 50

Somatic motor neurons in the spinal cord control all of the following muscles, except those that

A) position the pectoral girdle.
B) move the arm.
C) move the hand and fingers.
D) move the face.
E) move the forearm and hand.

Question 51

The ________ nerve, which arises in the cervical plexus, innervates the diaphragm.

A) ansa cervicalis
B) lesser occipital
C) radial
D) phrenic
E) sciatic

Question 52

Figure 12-2 Spinal Nerves
Use Figure 12-2 to answer the following questions:
Identify the structure labeled "6."

A) autonomic nerve
B) sympathetic ganglion
C) dorsal root ganglion
D) rami communicantes
E) ventral root

Question 53

The ________ of each spinal nerve innervates the skin and muscles of the back.

A) white ramus communicantes
B) gray ramus communicantes
C) dorsal ramus
D) ventral ramus
E) dermatome

Question 54

A dorsal and ventral root of each spinal segment unite to form a

A) cervical enlargement.
B) lumbar enlargement.
C) spinal nerve.
D) spinal meninx.
E) spinal ganglion.

Question 55

If the dorsal root of a spinal nerve is severed,

A) output to skeletal muscles would be blocked.
B) output to visceral organs would be blocked.
C) the spinal cord would not be able to process information at that level.
D) the brain would not be able to communicate with that level of the spinal cord.
E) sensory input would be blocked.

Question 56

Figure 12-2 Spinal Nerves
Use Figure 12-2 to answer the following questions:
Identify the structure labeled "5."

A) autonomic nerve
B) autonomic ganglion
C) rami communicantes
D) dorsal root ganglion
E) ventral root

Question 57

The preganglionic fibers that carry visceral motor fibers and connect a spinal nerve with an sympathetic ganglion form the

A) white rami communicantes.
B) gray rami communicantes.
C) dorsal ramus.
D) ventral ramus.
E) dermatomes.

Question 58

The complex, interwoven network formed by contributions from the ventral rami of neighboring spinal nerves is termed a(n)

A) dermatome.
B) autonomic nerve.
C) lateral nerve.
D) tract.
E) plexus.

Question 59

The ventral rami form four major plexuses, including all of the following, except the ________ plexus.

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

Question 60

If a person has a crush injury to the C₃-C₅ spinal segments, you would expect that he

A) might be unable to breathe on his own.
B) could walk without difficulty.
C) would have full range of motion in all extremities.
D) would be in a coma.
E) would exhibit none of the above.

Question 61

The obturator nerve is distributed to the

A) adductors of the hip.
B) skin over the perineum.
C) extensors of the hip.
D) skin over buttocks.
E) biceps femoris.

Question 62

Reflexes can be classified according to all of the following, except

A) their development.
B) where information processing occurs.
C) the motor response.
D) the complexity of the neural circuit.
E) whether they are sensory or motor.

Question 63

Recognized neuronal circuit patterns include all of the following, except

A) convergent.
B) divergent.
C) multipolar.
D) reverberating.
E) parallel processing.

Question 64

In which plexus does the ulnar nerve arise?

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

Question 65

Reflexes based on synapses formed during development are ________ reflexes.

A) visceral
B) innate
C) acquired
D) somatic
E) vegetative

Question 66

The ________ reflex complements the flexor reflex by activating contralateral muscles.

A) stretch
B) tendon
C) flexor
D) crossed extensor
E) reciprocal

Question 67

All of the following are True of neural reflexes, except that they

A) are automatic motor responses.
B) are the simplest form of behavior.
C) help preserve homeostasis.
D) cannot be modified by the brain.
E) involve at least two neurons.

Question 68

The flexor reflex

A) prevents a muscle from overstretching.
B) prevents a muscle from generating damaging tension.
C) moves a limb away from a painful stimulus.
D) usually depends on cranial neurons.
E) is an example of a monosynaptic reflex.

Question 69

All of the following are True of polysynaptic reflexes, except that they

A) are arranged according to dermatomes.
B) are intersegmental in distribution.
C) involve reciprocal innervation.
D) have reverberating circuits that prolong the reflexive motor response.
E) involve pools of interneurons.

Question 70

In which of the following would the delay between stimulus and response be greater?

A) a monosynaptic reflex
B) a polysynaptic reflex

Question 71

Spinal interneurons inhibit antagonist motor neurons in a process called

A) a crossed extensor reflex.
B) a stretch reflex.
C) a tendon reflex.
D) reciprocal inhibition.
E) reverberating circuits.

Question 72

Each of the following nerves originates in the lumbar plexus, except the ________ nerve.

A) saphenous
B) sciatic
C) femoral
D) obturator
E) genitofemoral

Question 73

The stretch reflex

A) is an example of a polysynaptic reflex.
B) is important in regulating muscle length.
C) involves a receptor called the Golgi tendon organ.
D) is activated when a smooth muscle lengthens.
E) none of the above

Question 74

Which of the following is not True about a positive Babinski reflex?

A) normal in newborns
B) abnormal in adults
C) a sign of injury to descending spinal tracts
D) causes you to close your eyes when you sneeze
E) causes flaring of the toes when the sole is stroked

Question 75

All of the following are True of muscle spindles, except that they

A) are found within skeletal muscle.
B) consist of specialized fibers called intrafusal fibers.
C) are found in tendons.
D) are the receptor for the stretch reflex.
E) are innervated by gamma motor neurons.

Question 76

Tina falls while climbing a tree and lands on her back. Her frightened parents take her to the emergency room, where she is examined. Her knee-jerk reflex is normal and she exhibits a plantar reflex (negative Babinski reflex). These results suggest that

A) Tina has injured one of her descending nerve tracts.
B) Tina has injured one of her ascending nerve tracts.
C) Tina has a spinal injury in the lumbar region.
D) Tina has a spinal injury in the cervical region.
E) Tina suffered no damage to her spinal cord.

Question 77

As the ________ nerve approaches the knee, it divides into two branches, the fibular nerve and the tibial nerve.

A) perineal
B) femoral
C) brachial
D) pudendal
E) sciatic

Question 78

The ventral rami of spinal nerves C4 to T1 contribute fibers to the ________ plexus.

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

Question 79

The reflex that prevents a muscle from exerting too much tension is the ________ reflex.

A) stretch
B) tendon
C) flexor
D) crossed extensor
E) reciprocal

Question 80

The brachial plexus gives rise to all of the following nerves, except the

A) radial.
B) median.
C) ulnar.
D) musculocutaneous.
E) phrenic.