MAP Chapter 13
The final step involved in a neural reflex is __________. a response by an effector information processing the activation of a sensory neuron the activation of a motor neuron
A response by an effector
The dorsal root of a spinal nerve contains axons of sensory neurons. interneurons. axons of motor neurons. cell bodies of motor neurons. cell bodies of sensory neurons.
Axons of sensory neurons
The neural "wiring" of a single reflex is called a(n) ganglion. tract. intershoot. ramus. reflex arc.
Reflex arc
Clenching the fists often enhances the knee jerk reflex. This is an example of __________. reinforcement positive feedback nerve injury stimulus response
Reinforcement
The dorsal root contains ________ neurons. efferent unipolar motor sensory interneurons
Sensory
If the dorsal root of a spinal nerve is severed, output to skeletal muscles would be blocked. the spinal cord would not be able to process information at that level. output to visceral organs would be blocked. sensory input would be blocked. the brain would not be able to communicate with that level of the spinal cord.
Sensory input would be blocked
The posterior horns of the spinal cord contain mainly sensory nuclei. sympathetic nuclei. nerve tracts. autonomic motor nuclei. somatic motor nuclei.
Sensory nuclei
The dorsal root of a spinal nerve is the site for __________ neurons, whereas the ventral root is the site of __________ neurons. efferent; afferent CNS; PNS sensory; motor motor; sensory
Sensory; motor
Anatomically, the spinal cord is part of the __________, and the spinal nerves are part of the __________. motor division; sensory division somatic division; autonomic division PNS; CNS CNS; PNS
CNS; PNS
All of the following are true of neural reflexes except that they help preserve homeostasis. are the simplest form of behavior. cannot be modified by the brain. are automatic motor responses. involve at least two neurons.
Cannot be modified by the brain.
The dorsal root ganglia mainly contain synapses. cell bodies of motor neurons. axons of motor neurons. cell bodies of sensory neurons. axons of sensory neurons.
Cell bodies of sensory neurons
The dorsal root ganglia consist mainly of __________. cell bodies of multipolar neurons axons of multipolar neurons cell bodies of unipolar neurons axons of unipolar neurons
Cell bodies of unipolar neurons
The spinal cord is part of the ________ nervous system. central autonomic afferent peripheral somatic
Central
In the spinal cord, the cerebrospinal fluid is found within the __________. subarachnoid and epidural spaces subdural and epidural spaces central canal and subarachnoid space central canal and epidural space
Central canal and subarachnoid space
The trapezius muscle is innervated by nerves from which plexus? brachial sacral cervical lumbar
Cervical
Reflexes that activate muscles on the opposite side of the body as the stimulus are called commensual. ipsilateral. contralateral. parasympathetic. involuntary.
Contralateral
The ________ reflex complements the flexor reflex by activating contralateral muscles. tendon flexor reciprocal crossed extensor stretch
Crossed extensor
The __________ reflex is a polysynaptic reflex that involves activating muscles contralateral to the receptor. stretch tendon crossed extensor flexor
Crossed extensor
You have a pair of new sneakers. As you walk along the corridor, your foot catches. Immediately, your body responds and you are able to catch yourself before falling. Which reflex was executed? stretch reflex tendon reflex crossed extensor reflex withdrawal reflex
Crossed extensor reflex
When sensory information is relayed from one part of the brain to another, the pattern is called __________. reverberation serial processing convergence parallel processing
Serial processing
Consider the steps of a reflex arc. Which step follows information processing? activation of a motor neuron response of a peripheral effector activation of a sensory neuron arrival of a stimulus and activation of a receptor
Activation of a motor neuron
A reflex arc always includes a(n) __________. afferent axon sensory receptor efferent axon All of the listed responses are correct.
All
In meningitis, inflammation of the meninges occurs. CSF flow can be disrupted. bacteria can be the cause. viruses can be the cause. All of the answers are correct.
All
Which of the following is an example of the brain modifying reflex patterns? when someone keeps postponing emptying a full urinary bladder when a person deliberately walks on hot coals when someone holds their breath All of the listed responses are correct.
All
Which of the following nerves do not innervate the ankle and the foot? sural nerve a branch of the sciatic nerve fibular nerve All of these nerves innervate the ankle and the foot.
All of these nerves innervate the ankle and the foot.
The ventral root of a spinal nerve contains axons of sensory neurons. cell bodies of sensory neurons. axons of motor neurons. interneurons. cell bodies of motor neurons.
Axons of motor neurons
An example of the brain affecting spinal reflexes is the replacement of the __________ by the __________. Babinski sign; flexor reflex flexor reflex; plantar reflex plantar reflex; Babinski sign Babinski sign; plantar reflex
Babinski sign; plantar reflex
Spinal nerves are both sensory and motor. involuntary. purely motor. interneuronal. purely sensory.
Both sensory and motor
Spinal nerves are classified as mixed nerves because they contain __________. both sensory and motor fibers white matter and gray matter both dorsal and ventral roots ascending and descending pathways
Both sensory and motor fibers
The white matter of the spinal cord contains sensory and motor nuclei. interneurons. both axons and dendrites. bundles of dendrites with common origins, destinations, and functions. bundles of axons with common origins, destinations, and functions.
Bundles of axons with common origins, destinations, and functions.
Pain receptors are the __________. axons of motor neurons dendrites of sensory neurons activators of motor neurons specialized cells that respond to a limited range of stimuli
Dendrites of sensory neurons
In what pattern of neural processing does one neuron synapse with several neurons? reverberation divergence convergence serial processing
Divergence
The ________ of each spinal nerve innervates the skin and muscles of the back. ventral ramus gray ramus communicantes dermatome white ramus communicantes dorsal ramus
Dorsal ramus
The tough, fibrous, outermost covering of the spinal cord is the periosteum. arachnoid. dura mater. epidural block. pia mater.
Dura mater
The condition in which a person loses all feeling and movement of the arms and legs due to spinal cord injury is termed spinal shock. quadriplegia. paraplegia. spinal transection. hemiplegia.
Quadriplegia
The connective tissue layer that covers Schwann cells is the __________. endoneurium epineurium perineurium endomysium
Endoneurium
April stubs her left hallux as she is walking to the kitchen at night. Which nerve and which plexus are involved in the sensation of pain sent to her brain? median nerve and brachial plexus tibial nerve and sacral plexus sciatic nerve and lumbar plexus fibular nerve and sacral plexus
Fibular nerve and sacral plexus
Which of the following statements about shingles is FALSE? A person who has had chickenpox could get shingles. It is an inflammation of spinal nerves and their corresponding dermatomes. Fortunately, shingles, like chickenpox, can be experienced only once in life. It is caused by the varicella zoster virus.
Fortunately, shingles, like chickenpox, can be experienced only once in life.
Neuronal pools are described as __________. motor neurons that converge to a ganglion sensory nerves that converge to form the plexuses isolated clusters of neurons in the CNS functional groups of interconnected neurons
Functional groups of interconnected neurons
The highest level of motor control involves a series of interactions that occur __________. in centers in the brain that can modulate or build on reflexive motor patterns as monosynaptic reflexes that are rapid but stereotyped in the descending pathways that provide facilitation and inhibition in the gamma efferents to the intrafusal fibers
In centers in the brain that can modulate or build on reflexive motor patterns
Reflexes based on synapses formed during development are ________ reflexes. somatic innate acquired vegetative visceral
Innate
Which of these is NOT one of the essential components of a monosynaptic reflex? integration processing in the CNS receptor activation input by a sensory neuron output to a peripheral effector
Integration processing in the CNS
The most abundant category of neurons is __________. visceral motor somatic afferents somatic motor interneurons
Interneurons
The most complicated spinal reflexes are called ipsilateral reflex arcs. spinal plexuses. intersegmental reflex arcs. collateral reflex arcs. dermatomes.
Intersegmental reflex arcs.
Reflexes that activate muscles on the same side of the body as the stimulus are called commensual. parasympathetic. ipsilateral. involuntary. contralateral.
Ipsilateral
Which of the following is NOT a property of the stretch reflex? Its receptor is muscle spindle. It is a disynaptic reflex. It regulates muscle length. It is activated by muscle elongation.
It is a disynaptic reflex.
In an adult, the conus medullaris is found at about L5. L1. T6. C1. T10.
L1
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? problems moving his legs inability to breathe problems with moving his arms uncontrollable sweating of his feet loss of sensation in his torso
Loss of sensation in his torso
During the procedure known as a(n) ________, a needle is inserted into the subarachnoid space in the inferior lumbar region. thoracic tap laminectomy encephalomyelogram lumbar puncture EEG
Lumbar puncture
Which of the following is an example of a visceral reflex? micturition (urinary) reflex withdrawal reflex stretch reflex crossed extensor reflex
Micturition (urinary) reflex
The flexor reflex usually depends on cranial neurons. moves a limb away from a painful stimulus. prevents a muscle from generating damaging tension. is an example of a monosynaptic reflex. prevents a muscle from overstretching.
Moves a limb away from a painful stimulus
The sensory receptors in the stretch reflex are the __________. Pacinian corpuscles muscle spindles Meissner's corpuscles Golgi tendon organs
Muscle spindles
Which of the following nerves is not part of the sensory innervation in the hand? musculocutaneous nerve radial nerve median nerve ulnar nerve
Musculocutaneous nerve
The white ramus is the branch of a spinal nerve that consists of __________. myelinated preganglionic axons myelinated postganglionic axons unmyelinated postganglionic axons unmyelinated preganglionic axons
Myelinated preganglionic axons
Which of the following is NOT found in the CNS? neuron cell bodies located in nuclei the cerebral cortex of the brain neuron cell bodies located in ganglia the gray and white matter of the spinal cord
Neuron cell bodies located in ganglia
Interneurons are organized into functional groups called spindles. plexi. neuronal pools. perineuria. rami.
Neuronal pools
In a spinal reflex, information flows from __________ to __________ to __________. CNS; PNS; CNS CNS; CNS; PNS PNS; PNS; CNS PNS; CNS; PNS
PNS; CNS; PNS
You are sitting at a Mexican restaurant waiting for your food. The waiter brings a very hot plate, telling you to be careful about touching it. You touch it anyway, producing a pain sensation in your fingers, a withdrawal of your hand, and an auditory comment of what you are thinking. This scenario represents a ________ neuronal circuit. consensual reverberation parallel convergent serial
Parallel
The layer of the meninges in direct contact with the spinal cord is the arachnoid. choroid plexus. pia mater. dura mater. subarachnoid space.
Pia mater
The cerebrospinal fluid (CSF) is confined between the __________ and the __________. pia mater; arachnoid mater pia mater; dura mater dura mater; arachnoid mater epidural space; subdural space
Pia mater; arachnoid mater
The __________ gray horns contain sensory nuclei. lateral posterior intermediate ventral
Posterior
In reference to the vertebral column, C2 refers to the cervical nerve that __________. is between vertebrae C2 and C3 precedes vertebra C2 follows vertebra C2 precedes vertebra C3
Precedes vertebrae C2
While building a doghouse, Tom misses the nail and hits his thumb with the hammer instead. The pain sensation is immediate and intense. Which of the following is the pattern of neuronal pool interaction most likely to process that sensation? divergence reverberation serial processing parallel processing
Serial processing
Parallel processing is the "neural circuit" in which __________. several neurons or neuronal pools process the same information at one time several neurons synapse on the postsynaptic neuron use of positive feedback stimulates presynaptic neurons a specific input is broadly distributed
Several neurons or neuronal pools process the same information at one time
The brachial plexus innervates the __________. thorax and arm shoulder girdle and arm neck and shoulder girdle neck and arm
Shoulder girdle and arm
________ reflexes activate skeletal muscles. Cranial Autonomic Somatic Involuntary Spinal
Somatic
A dorsal and ventral root of each spinal segment unite to form a spinal ganglion. spinal meninx. cervical enlargement. spinal nerve. lumbar enlargement.
Spinal nerve
To withdraw cerebrospinal fluid during a spinal tap, a needle is inserted into the __________. subarachnoid space epidural space pia mater subdural space
Subarachnoid space
The lumbo-sacral plexus that supplies the pelvic girdle and the leg includes the spinal nerves __________. L4-S4 T12-L4 T12-S4 T1-T12
T12-S4
The polysynaptic reflex that limits muscle tension is the __________ reflex. flexor postural tendon stretch
Tendon
The subdural space lies between the arachnoid mater and the pia mater. the pia mater and the dura mater. the endosteum and the periosteum. the dura mater and the arachnoid mater. the pia mater and the subarachnoid space.
The dura mater and the arachnoid mater
Anesthetics administered into the epidural space are advantageous because __________. the effect can easily be carried throughout the spinal cord region by way of cerebrospinal fluid the effect is localized and only sensory the effects are long lasting, even with just a single injection the patient experiences both sensory loss and paralysis temporarily
The effect is localized and only sensory
The major anatomical difference between gray matter and white matter is __________. that white matter is located deep to the gray matter that white matter is primarily in the CNS that gray matter is functionally organized into tracts the presence of myelinated axons
The presence of myelinated axons
Damage to which branch of the spinal nerve is likely only to have an effect on the muscles of the limbs? The dorsal ramus The ventral ramus Sympathetic nerve The rami communicantes
The ventral ramus
General characteristics of polysynaptic reflexes include all of the following EXCEPT that __________. they involve reciprocal inhibition several reflexes may cooperate, producing a coordinated reflex they have reverberating circuits they do not involve interneurons
They do not involve interneurons
The spinal cord consists of four regions and ________ segments. twenty-five five thirty-one twelve The number varies widely among individuals.
Thirty-one
Shingles that manifest themselves in close proximity to the umbilical region stem from an infection within spinal nerves emerging from which spinal segments? sacral lumbar cervical thoracic
Thoracic
Reflexes can be classified according to all of the following except the motor response. where information processing occurs. their development. whether they are sensory or motor. the complexity of the neural circuit.
Whether they are sensory or motor
Nerve tracts or fasciculi make up the central canal. white columns. posterior gray horns. anterior gray horns. gray commissures.
White columns
Which of the following is not true about a positive Babinski reflex? flaring of the toes when the sole is stroked a sign of injury to descending spinal tracts why you close your eyes when you sneeze abnormal in adults normal in newborns
Why you close your eyes when you sneeze
The delicate connective tissue fibers that surround individual axons of spinal nerves compose a layer called the __________. commissures epineurium endoneurium perineurium
endoneurium