Chapter 14 - M2
Polysynaptic reflex arcs differ from monosynaptic reflex arcs in that the former have ________, which are not present in the latter. A) an interneuron or interneurons B) stimuli C) specific receptors D) cranial processing centers E) spinal cord processing centers
A) an interneuron or interneurons
The middle layer of the meninges, which consists of simple squamous epithelium, is called (the) ________. A) arachnoid mater B) pia mater C) periosteum D) dura mater E) epideural space
A) arachnoid mater
Which of the following is defined as the tough, fibrous sheath that forms the outermost layer of a peripheral nerve? A) epineurium B) endoneurium C) perineurium D) neurilemma E) fascicle
A) epineurium
The largest nerve in the body that is formed from L4-S3 is the ________. A) tibial nerve B) pudendal nerve C) sciatic nerve D) fibular nerve E) superior gluteal nerve
C) sciatic nerve
The pia mater is the ________. A) meninx that forms denticulate ligaments B) outermost covering over the brain, but not the spinal cord C) toughest and thickest of the meninges D) meninx that contains cerebrospinal fluid E) meninx that forms the major component of the coccygeal ligament
A) meninx that forms denticulate ligaments
The ________ nerve, which is formed by the ventral rami of S2-S4, innervates muscles of the perineum, including the urethral sphincter muscles. A) pudendal B) posterior femoral cutaneous C) sciatic D) inferior gluteal E) superior gluteal
A) pudendal
Distally, the connective tissue of the ________ is continuous with the connective tissue sheath around each spinal nerve. A) spinal dura mater B) filum terminale C) spinal pia mater D) spinal arachnoid mater E) arachnoid granulations
A) spinal dura mater
The first branch of each spinal nerve, which communicates with an autonomic ganglion, is myelinated and is called a(n) ________. A) white ramus B) gray commissure C) fascicle D) postganglionic fiber E) gray ramus
A) white ramus
A normal patellar reflex indicates that spinal nerves and spinal segments ________ are undamaged. A) C1-C3 B) L2-L4 C) C5-C7 D) T1-L2 E) L5-S2
B) L2-L4
Motor patterns that are learned, like walking, are called ________ reflexes. A) somatic B) acquired C) autonomic D) visceral E) learned
B) acquired
The median nerve ________. A) arises from the medial cord of the brachial plexus B) arises from both the medial and lateral cords of the brachial plexus C) arises from the posterior cord of the brachial plexus D) innervates the pronators of the forearm E) is a major nerve of the cervical plexus
B) arises from both the medial and lateral cords of the brachial plexus
Activation of a motor neuron during the processing of a reflex action ________. A) occurs instantaneously, with the start of the stimulation B) carries the nerve impulse to the peripheral effector organs C) typically enhances the original stimulus that triggered the reflex D) sends a response to peripheral structures by way of the dorsal root of a spinal nerve E) sends impulses through the dorsal root ganglion
B) carries the nerve impulse to the peripheral effector organs
The H-shaped mass in the center of the spinal cord is dominated by ________. A) large numbers of myelinated and unmyelinated axons B) cell bodies of neurons and glial cells C) motor axons only D) dura mater E) connective tissue and blood vessels
B) cell bodies of neurons and glial cells
The anterior horns are the largest in the ________ regions. A) thoracic and lumbar B) cervical and lumbar C) cervical and thoracic D) lumbar and sacral E) cervical and sacral
B) cervical and lumbar
Caudally, the spinal dura mater blends with components of the ________ to form the coccygeal ligament. A) dorsal root ganglia B) filum terminale C) ventral root D) spinal nerves E) cauda equina
B) filum terminale
Axons, which cross from one side to the other in the spinal cord, pass through the ________. A) anterior white commissure B) gray commissure C) posterior white commissure D) anterior gray horns E) denticulate ligaments
B) gray commissure
The spinal nerves form through the fusion of dorsal and ventral nerve roots as they pass through a(n) ________. A) plexus B) intervertebral foramen C) gray commissure D) vertebral foramen E) transverse foramen
B) intervertebral foramen
Which of the following is a nerve of the cervical plexus? A) median nerve B) lesser occipital nerve C) nerve to subclavius D) axillary nerve E) musculocutaneous nerve
B) lesser occipital nerve
The stretch reflex is an example of a ________ reflex because it maintains the body's upright position. A) motor B) postural C) sensory D) interneuron E) lumbar
B) postural
"Saturday night palsy" results from pressure on the back of the arm, interrupting the function of which nerve? A) median B) radial C) ulnar D) axillary E) musculocutaneous
B) radial
From medial to lateral, brachial plexus structures are organized as which of the following? A) roots—divisions—cords—trunks—nerves B) roots—trunks—divisions—cords—nerves C) cords—nerves—roots—trunks—divisions D) nerves—cords—divisions—trunks—roots E) trunks—cords—roots—divisions—nerves
B) roots—trunks—divisions—cords—nerves
The ________ of the spinal nerves is/are the portion(s) that participate(s) in the formation of nerve plexuses. A) dorsal root ganglia B) ventral rami C) posterior columns D) epineurium E) dorsal rami
B) ventral rami
The "rami communicantes" exist for spinal nerves ________. A) C1 to T1 B) C1 to L2 C) T1 to L2 D) L1 to S1 E) T1 to S1
C) T1 to L2
7) Bundles of fiber known as ________ extend from the inner surface of the arachnoid mater to the outer surface of the pia mater. A) arachnoid granulations B) cauda equina C) arachnoid trabeculae D) subarachnoid spaces E) denticulate ligaments
C) arachnoid trabeculae
The ventral root of a spinal nerve contains ________. A) axons of sensory neurons B) ventral rami C) axons of motor neurons D) cell bodies of motor neurons E) interneurons
C) axons of motor neurons
The filum terminale and ventral and dorsal spinal cord roots extending distal to the conus medullaris are collectively referred to as the ________. A) collateral ganglia B) denticulate ligaments C) cauda equina D) spinal meninges E) motor neurons
C) cauda equina
The rhomboids (major and minor) are innervated by which of the following? A) brachial plexus nerves B) sacral plexus nerves C) cervical plexus nerves D) hypoglossal nerve E) lumbar plexus nerves
C) cervical plexus nerves
The body surface region monitored by a specific pair of spinal nerves is called (a) ________. A) ramus communicantes B) ventral ramus C) dermatome D) perineurium E) tract
C) dermatome
Motor fibers travel in the ________ of the spinal cord. A) ascending tracts B) medial tracts C) descending tracts D) posterior tracts E) lateral tracts
C) descending tracts
The short head of the biceps femoris and the tibialis anterior muscles are innervated by the ________ nerve. A) iliohypogastric B) pudendal C) fibular D) inferior gluteal E) lateral femoral cutaneous
C) fibular
The nuclei in the spinal cord that contain the cell bodies of the visceral motor neurons are located in (the) ________. A) posterior gray horns B) anterior gray horns C) lateral gray horns D) gray commissures E) ventral roots
C) lateral gray horns
Inferior to the ________, the spinal cord tapers to the conus medullaris. A) cervical enlargement B) cauda equina C) lumbosacral enlargement D) filum terminale E) dorsal root ganglia
C) lumbosacral enlargement
In step 4 of a neural reflex, a(n) ________ stimulated to threshold conducts action potentials along its axons into the periphery. A) sensory neuron B) dorsal root ganglia C) motor neuron D) dorsal horn E) interneuron
C) motor neuron
The ________ arises from the posterior cord of the brachial plexus. A) ulnar nerve B) median nerve C) radial nerve D) musculocutaneous nerve E) dorsal scapular nerve
C) radial nerve
Activation of a sensory neuron results in the conduction of action potentials into the spinal cord along a(n) ________. A) efferent fiber B) ventral ramus C) ventral horn D) afferent fiber E) peripheral effector
D) afferent fiber
The ulnar nerve is found in the ________ plexus. A) cervical B) thoracic C) lumbar D) brachial E) sacral
D) brachial
Sites where information regarding reflexes is processed include the spinal cord and the ________. A) skeletal muscles B) dorsal root ganglia C) visceral muscles D) brain E) ventral roots
D) brain
Every spinal cord segment is associated with a pair of ________, which contain the cell bodies of sensory neurons. A) ventral roots B) mixed nerves C) peripheral effectors D) dorsal root ganglia E) dorsal horns
D) dorsal root ganglia
The innermost layer of connective tissue fibers and isolated fibrocytes, which surrounds each axon is the ________. A) fascicle B) fasciculus C) epineurium D) endoneurium E) perineurium
D) endoneurium
The subarachnoid space is ________. A) between the arachnoid mater and the underlying dura mater B) filled with fat C) between the arachnoid mater and the periosteum D) filled with cerebrospinal fluid E) a potential space only
D) filled with cerebrospinal fluid
The gray matter of the spinal cord is organized into anterior, posterior, and lateral ________. A) tracts B) columns C) commissures D) horns E) ganglia
D) horns
Spinal reflexes ________. A) include monosynaptic reflexes only B) involve only a single segment of the spinal cord C) always transmit information to the brain for processing D) include both monosynaptic and polysynaptic reflexes E) do not include stretch reflexes
D) include both monosynaptic and polysynaptic reflexes
Select the association that is most closely matched. A) anterior gray horns—visceral sensory nuclei B) anterior gray horns—visceral motor neurons C) posterior gray horns—somatic motor neurons D) posterior gray horns—visceral sensory nuclei E) lateral gray horns—somatic motor neurons
D) posterior gray horns—visceral sensory nuclei
The gray and white rami from T1 to L2, which allow information exchange between the spinal nerves and the autonomic ganglia are collectively called the ________. A) commissures B) horns C) columns D) rami communicantes E) fascicles
D) rami communicantes
All of the following are TRUE of fiber tracts in the spinal cord EXCEPT ________. A) all axons within a tract relay information in the same direction B) each tract carries sensory or motor information, but not both C) axons of a single tract are relatively uniform in diameter, myelination, and conduction speed D) the tracts are randomly located with respect to the type of information carried E) axons of a single tract are relatively uniform with respect to myelination
D) the tracts are randomly located with respect to the type of information carried
Reflexes that control the actions of smooth muscles and glands are classified as ________ reflexes. A) somatic B) monosynaptic C) spinal D) visceral or autonomic E) acquired
D) visceral or autonomic
Which of the following is TRUE regarding visceral reflexes? A) They are never classified as autonomic reflexes. B) They control skeletal muscle contractions. C) They include superficial reflexes. D) They include stretch reflexes. E) They control the actions of smooth muscles and glands.
E) They control the actions of smooth muscles and glands.
Brachial plexus nerves arise from one or more trunks or cords whose neurons indicate their positions relative to the ________. A) brachial artery B) clavicle C) subclavius muscle D) C4 vertebra E) axillary artery
E) axillary artery
The epidural space contains areolar and adipose tissue, in addition to ________. A) cerebrospinal fluid B) lymph C) denticulate ligaments D) gray matter E) blood vessels
E) blood vessels
The ________ nerve of the lumbar plexus is formed by ventral rami of T12 and L1, and innervates the internal and external oblique muscles. A) genitofemoral B) lateral femoral cutaneous C) ilioinguinal D) subcostal E) iliohypogastric
E) iliohypogastric
The term for a reflex that is genetically determined is a(n) ________ reflex. A) acquired B) cranial C) spinal D) monosynaptic E) innate
E) innate
The blood vessels that supply the spinal cord are found in the ________. A) dura mater B) epidural space C) subarachnoid space D) arachnoid mater E) pia mater
E) pia mater