Seeley's Anatomy & Physiology 11th ed Chapter 12
72. Spinal nerves exiting the cord from the level of L4 to S4 form the
sacral plexus.
122. The largest peripheral nerve in the body is the ______ nerve.
sciatic
76. 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.
sciatic
33. The knee-jerk reflex involves which of the following?
sensory and motor neurons
Match the term with the correct definition: epidural space
separates dura mater from periosteum
Match the disorder with its description: meningitis
stiffness in the neck and headache
39. Stimulation of the Golgi tendon organs result in which of the following changes in the reflex arc?
stimulation of an inhibitory neuron and decreased action potentials in alpha motor neurons
69. When someone taps you on your shoulder, they stimulate the ____ nerve.
axillary
Match the term with the most appropriate description: a reflex that helps prevent falls
crossed extensor reflex
Cutaneous sensory distribution of a spinal nerve can be mapped as a ________.
dermatome
56. The cutaneous sensory distribution of a spinal nerve can be mapped as a
dermatome.
62. Damage to the phrenic nerve would result in
difficulty breathing.
59. The branch of a spinal nerve that innervates deep muscles on the dorsal thorax is the
dorsal ramus.
15. The sensory root of a spinal nerve is also referred to as
dorsal root.
6. The thickest of the meninges is the
dura mater.
32. Muscles and glands that are capable of producing a response when stimulated by motor neurons are called
effectors.
51. There are ________ cervical spinal nerves.
eight
9. What space, found between the vertebral wall and the dura mater, is the area for injecting anesthesia for childbirth?
epidural space
120. In the PNS, nerves are held together by
epineurium
123. Branches of the pudendal nerve are anesthetized during childbirth before the doctor performs a(an) _______________.
episiotomy
42. Initiating the withdrawal reflex in both legs at the same time would cause one to
fall.
78. 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?
femoral
11. What structure anchors the thecal sac and conus medullaris to the coccyx?
filum terminale
3. The spinal cord begins at the
foramen magnum.
Match the term with the correct definition: reflex arc
functional unit of the nervous system
Match the term with the most appropriate description: the knee-jerk
stretch reflex
22. Structurally, the simplest reflex is the
stretch reflex.
10. During a spinal tap, cerebrospinal fluid is obtained from which of the following locations?
subarachnoid space
12. Where is cerebrospinal fluid found around the spinal cord?
subarachnoid space
45. The endoneurium
surrounds individual axons and their Schwann cells.
1. There are _____ enlargements of the spinal cord where nerves supplying the extremities enter and leave.
two
66. When a person hits their funny bone, they cause temporary damage to the _____ nerve.
ulnar
60. Intercostal nerves are formed from the
ventral rami of thoracic spinal nerves.
16. The motor root of a spinal nerve is also referred to as the
ventral root.
35. 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?
-muscles of the back are stretched -the muscle spindle is stretched -action potentials in sensory neurons of the muscle spindles increase -action potentials in alpha motor neurons of skeletal muscle fibers increase -skeletal muscle of the back contract
27. Place the following parts of a reflex arc in the correct order beginning with the sensory receptor.
-sensory receptor -sensory neuron -interneuron -motor neuron -effector
5. The spinal cord ends at the
2nd lumbar vertebrae.
49. Which of the following combinations indicates the correct distribution of spinal nerve pairs?
8 cervical - 12 thoracic - 5 lumbar - 5 sacral - 1 coccygeal
motor neuron
80. Label component "A" on the reflex arc.
sensory neuron
81. Label component "B" on the reflex arc.
interneuron
82. Label component "C" on the reflex arc.
sensory receptor
83. Label component "D" on the reflex arc.
effector organ
84. Label component "E" on the reflex arc.
cervical enlargement
85. What does "A" represent?
spinal nerves
86. What does "B" represent?
conus medullaris
87. What does "C" represent?
cauda equina
88. What does "D" represent?
filium terminale
89. What does "E" represent?
dorsal root
90. What does "A" represent?
dorsal root ganglion
91. What does "B" represent?
spinal nerve
92. What does "C" represent?
ventral root
93. What does "D" represent?
central canal
94. What does "E" represent?
26. 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 these choices are correct.
50. A collapsed intervertebral foramen could affect all of the following spinal nerves EXCEPT
C1
38. Sam is curling very heavy weights and suddenly drops them. Which reflex forced this action by Sam to prevent tendon damage?
Golgi tendon reflex
Match the term with the most appropriate description: partially responsible for a weight lifter suddenly dropping a weight that is too heavy
Golgi tendon reflex
37. The reflex that prevents excessive tension in a muscle is the
Golgi tendon reflex.
21. What is found the lateral gray horns of the spinal cord?
The cell bodies of autonomic motor neurons.
20. What is found in the dorsal root ganglion?
The cell bodies of pseudo-unipolar sensory neurons.
19. What structure makes the dorsal root different from the ventral root?
The dorsal root has a ganglion.
13. Which of the following is false?
The posterior horn of the cord contains the cell bodies of motor neurons.
48. Which of the following statements concerning the structure of spinal nerves is true?
The ventral root contains motor or efferent fibers.
29. Stretch reflexes
aid in maintaining proper posture.
30. Which of the following events in a stretch reflex occurs last?
alpha motor neurons transmit action potentials to muscle causing contraction
8. The middle, thin, spider-like meninx is the
arachnoid mater.
23. Reflex arcs
are capable of receiving a stimulus and yielding a response.
25. Reflexes
are homeostatic.
31. Muscle spindles
are innervated by gamma motor neurons.
63. Spinal nerves C5-T1 make up the ____________ plexus.
brachial
Match the nerve with the appropriate description: tibial nerve
branches to form the medial and lateral plantar nerves
47. The perineurium
bundles axons into fascicles.
46. The epineurium
bundles fascicles into nerves.
55. Dermatomal maps are important clinically because they
can be used to help locate nerve damage.
18. In the spinal cord, white matter is organized into
columns and the gray matter into horns.
Match the disorder with its description: neuritis
inflammation of a nerve
Match the nerve to the correct function: median nerve
innervates all but one of the flexor muscles of the forearm and most of the hand muscles near the thumb
Match the nerve with the appropriate description: coccygeal plexus
innervates muscles of the pelvic floor
Match the nerve with the appropriate description: common fibular nerve
innervates the anterior and lateral muscles of the leg
Match the nerve to the correct function: axillary nerve
innervates the deltoid and teres minor muscles
Match the nerve with the appropriate description: femoral nerve
innervates the iliopsoas, sartorius, and quadriceps femoris
Match the nerve with the appropriate description: obturator nerve
innervates the muscles that adduct the thigh
Match the nerve to the correct function: radial nerve
innervates the triceps brachii
Match the nerve to the correct function: ulnar nerve
innervates two forearm muscles plus most of the intrinsic hand muscles
24. Which portion of a reflex arc is most likely to be located entirely within the central nervous system?
interneuron
4. The conus medullaris
is a tapered, cone like region immediately inferior to the lumbar enlargement.
43. Because the stretch reflexes can be traced back along certain spinal nerve routes,
it is possible to determine what level of the spinal cord may have been damaged.
2. The spinal cord
links the peripheral nervous system to the brain.
Match the disorder with its description: anesthesia
loss of sensation
52. A man was in an accident and severed his spinal cord between C6 and C7. Which of the following would NOT occur?
loss of use of the phrenic nerves and paralysis of the diaphragm
70. If you pinch your index finger in a door, pain sensations are carried via the ____ nerve.
median
67. An injury to the wrist that results in edema in the carpal tunnel would compress the
median nerve.
Match the term with the correct definition: dura mater
most superficial and thickest meninx
58. If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of
movement.
28. The sensory receptor of the stretch reflex is the
muscle spindle.
54. The brachial plexus supplies nerves that function to contract which of the following?
muscles of the arm and forearm
64. Which of the following nerves is part of the brachial plexus?
musculocutaneous
68. Using the biceps brachii to flex the forearm requires innervation of the _____ nerve.
musculocutaneous
71. Which of the following nerves is associated with the lumbosacral plexus?
obturator
77. Adduction of the thigh involves the
obturator nerve.
14. The ventral root of a spinal nerve contains
only motor fibers.
17. The cross-sectional view of the spinal cord reveals white matter on the
outside, gray matter on the inside, and a ventral motor root.
Match the disorder with its description: neuralgia
pain along a nerve tract
Match the disorder with its description: sciatica
pain radiating down the back of the thigh and leg
61. Which of the following nerves is a branch of both the cervical plexus and the brachial plexus?
phrenic
53. Damage to which of these nerves would be most life-threatening?
phrenic nerves
57. Ventral rami of some spinal nerves join with each other to form a
plexus.
44. The adaptive significance of the crossed extensor reflex when a person steps on a tack is to
prevent the person from falling down.
Match the nerve to the correct function: musculocutaneous nerve
provides motor innervation to the biceps brachii
79. Branches of the ____ nerve are anesthetized before a doctor performs an episiotomy for childbirth.
pudendal
65. Improper use of crutches could cause compression of the _____ nerve.
radial
Match the term with the most appropriate description: associated with withdrawal and stretch reflex
reciprocal innervation
124. The __________ __________ is the basic functional unit of the nervous system and is capable of receiving a stimulus and producing a response.
reflex arc
34. Gamma motor neurons
regulate the sensitivity of the muscle spindle.
41. Reciprocal innervation
reinforces the withdrawal reflex.
36. 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?
the knee-jerk reflex.
Match the term with the correct definition: pia mater
the meninx bound tightly to brain and spinal cord
Match the term with the correct definition: arachnoid mater
the middle meninx
7. The sac surrounding the spinal cord is the
thecal sac.
74. Which nerve is involved when a dancer points his/her toes?
tibial
75. The gastrocnemius muscle is most likely to be innervated by the _____ nerve.
tibial
73. The sciatic nerve is composed of the
tibial nerve and the common fibular nerve.
40. A reflex that protects limbs by removing them from painful stimuli is the
withdrawal reflex
Match the term with the most appropriate description: removing hand from a hot iron
withdrawal reflex
