QUESTIONS AND ANSWERS SURE A+
✔✔The spinal cord extends from the
A) medulla oblongata to the coccyx.
B) level of the third cervical vertebra to the coccyx.
C) level of the axis to the lowest lumbar vertebra.
D) medulla oblongata to the level of the second lumbar vertebra.
E) axis to the sacral hiatus. - ✔✔B) level of the third cervical vertebra to the coccyx.
✔✔The structure that anchors the inferior end of the spinal cord to the coccyx is the
A) conus medullaris.
B) cauda equina.
C) filum terminale.
D) lumbar enlargement.
E) posterior median sulcus. - ✔✔C) filum terminale.
✔✔Axons of sensory neurons synapse with the cell bodies of interneurons in the
_____________ of spinal cord gray matter.
A) anterior horn
B) lateral horn
C) posterior horn
D) gray commissure
E) lateral funiculi - ✔✔C) posterior horn
✔✔Cell bodies for sensory neurons are located in the
A) anterior horn of spinal cord gray matter.
B) lateral horn of spinal cord gray matter.
C) posterior horn of spinal cord gray matter.
D) dorsal root ganglia.
E) posterior columns. - ✔✔D) dorsal root ganglia.
✔✔Given these components of a reflex arc:
1. effector organ
2. interneuron
3. motor neuron
4. sensory neuron
5. sensory receptor
Choose the correct order an action potential follows after a sensory receptor is
stimulated.
A) 5,4,3,2,1
B) 5,4,2,3,1
C) 5,3,4,1,2
D) 5,2,4,3,1
E) 5,3,2,1,4 - ✔✔B) 5,4,2,3,1
,✔✔A reflex response accompanied by the conscious sensation of pain is possible
because of
A) convergent pathways.
B) divergent pathways.
C) a reflex arc that contains only one neuron.
D) sensory perception in the spinal cord. - ✔✔B) divergent pathways.
✔✔Several of the events that occurred between the time that a physician struck a
patient's patellar tendon with a rubber hammer and the time the quadriceps femoris
contracted (knee-jerk reflex) are listed below:
1. increased frequency of action potentials in sensory neurons
2. stretch of the muscle spindles
3. increased frequency of action potentials in the alpha motor neurons
4. stretch of the quadriceps femoris
5. contraction of the quadriceps femoris
Which of these lists most closely describes the sequence of events as they normally
occur?
A) 4,1,2,3,5
B) 4,1,3,2,5
C) 1,4,3,2,5
D) 4,2,1,3,5
E) 4,2,3,1,5 - ✔✔D) 4,2,1,3,5
✔✔_____________ are responsible for regulating the sensitivity of the muscle spindle.
A) Alpha motor neurons
B) Sensory neurons
C) Gamma motor neurons
D) Golgi tendon organs
E) Inhibitory interneurons - ✔✔C) Gamma motor neurons
✔✔Which of these events occurs when a person steps on a tack with the right foot?
A) The right foot is pulled away from the tack because of the Golgi tendon reflex.
B) The left leg is extended to support the body because of the stretch reflex.
C) The flexor muscles of the right thigh contract, and the extensor muscles of the right
thigh relax because of reciprocal innervation.
D) Extensor muscles contract in both thighs because of the crossed extensor reflex. -
✔✔C) The flexor muscles of the right thigh contract, and the extensor muscles of the
right thigh relax because of reciprocal innervation.
✔✔Which of these is a correct count of the spinal nerves?
A) 9 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
B) 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
C) 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
D) 8 cervical, 11 thoracic, 4 lumbar, 6 sacral, 1 coccygeal
, E) 7 cervical, 11 thoracic, 5 lumbar, 6 sacral, 1 coccygeal - ✔✔B) 8 cervical, 12
thoracic, 5 lumbar, 5 sacral, 1 coccygeal
✔✔Given these structures:
1. dorsal ramus
2. dorsal root
3. plexus
4. ventral ramus
5. ventral root
Choose the arrangement that lists the structures in the order that an action potential
passes through them, given that the action potential originates in the spinal cord and
propagates to a peripheral nerve.
A) 2,1,3
B) 2,3,1
C) 3,4,5
D) 5,3,4
E) 5,4,3 - ✔✔E) 5,4,3
✔✔Damage to the dorsal ramus of a spinal nerve results in
A) loss of sensation.
B) loss of motor function.
C) both a and b. - ✔✔C) both a and b.
✔✔A collection of spinal nerves that join together after leaving the spinal cord is called a
A) ganglion.
B) nucleus.
C) projection nerve.
D) plexus. - ✔✔D) plexus.
✔✔A dermatome
A) is the area of skin supplied by a pair of spinal nerves.
B) exists for each spinal nerve except C1
C) can be used to locate the site of spinal cord or nerve root damage.
D) all of the above. - ✔✔D) all of the above.
✔✔Which of these nerves arises from the cervical plexus?
A) median
B) musculocutaneous
C) phrenic
D) obturator
E) ulnar - ✔✔C) phrenic
✔✔The skin on the posterior surface of the hand is supplied by the
A) median nerve.
B) musculocutaneous nerve.
, C) ulnar nerve.
D) axillary nerve.
E) radial nerve. - ✔✔E) radial nerve.
✔✔Most the ulnar muscles and most of the flexor muscles of the forearm are supplied
by the
A) musculocutaneous nerve.
B) radial nerve.
C) median nerve.
D) ulnar nerve.
E) axillary nerve. - ✔✔C) median nerve.
✔✔Most intrinsic hand muscles are supplied by the
A) musculocutaneous nerve.
B) radial nerve.
C) median nerve.
D) ulnar nerve.
E) axillary nerve. - ✔✔D) ulnar nerve.
✔✔The sciatic nerve is actually two nerves combined within the same sheath. The two
nerves are the
A) femoral and obturator.
B) femoral and gluteal.
C) common fibular (peroneal) and tibial.
D) common fibular (peroneal) and obturator.
E) tibial and gluteal. - ✔✔C) common fibular (peroneal) and tibial.
✔✔The muscles of the anterior compartment of the thigh are supplied by the
A) obturator nerve.
B) gluteal nerve.
C) sciatic nerve.
D) femoral nerve.
E) ilioinguinal nerve. - ✔✔D) femoral nerve.
✔✔If a section is made that separates the brainstem from the rest of the brain, the cut is
between the
A) medulla oblongata and pons.
B) pons and midbrain.
C) midbrain and diencephalon.
D) thalamus and cerebrum.
E) medulla oblongata and spinal cord. - ✔✔C) midbrain and diencephalon.
✔✔Important centers for heart rate, blood pressure, respiration, swallowing, coughing,
and vomiting are located in the
A) cerebrum.