Deck 15: Sensory Pathways and the Somatic Nervous System

Question 1

Which of the following is/are sometimes called "prickling pain"?

A)mechanical damage
B)proprioception
C)extremes of temperature
D)fast pain
E)fast and slow pain

Answer 1

D

Question 2

Which of the following is not one of the special senses?

A)hearing
B)smell
C)taste
D)pressure
E)vision

Answer 2

D

Question 3

Thermoreceptors

A)are found within the dermis.
B)are free nerve endings.
C)for "cold" are structurally indistinguishable from those for "warm."
D)are more numerous for cold than for warm temperatures.
E)All of the answers are correct.

Answer 3

E

Question 4

Action potentials from receptors involved in general sensations are interpreted in the

A)premotor cortex.
B)primary sensory cortex.
C)general interpretive area.
D)mesencephalon.
E)reticular activating system.

Question 5

All of the following are true of a prickling pain sensations except that they

A)are carried by type A fibers.
B)reach the CNS quickly.
C)are interpreted by the pre-frontal cortex.
D)receive conscious attention.
E)often trigger somatic reflexes.

Question 6

In order for a sensation to become a perception,

A)it must be received by the somatosensory cortex.
B)the individual must vocalize about it.
C)it must arrive over fast-conducting nerve fibers.
D)the other senses must be silent.
E)it must be received by the pulvinar nucleus of the thalamus.

Question 7

The general senses

A)involve receptors that are relatively simple in structure.
B)are located in specialized structures called sense organs.
C)are localized to specific areas of the body.
D)cannot generate action potentials.
E)include taste and smell.

Question 8

The term general senses refers to sensitivity to all of the following,except

A)temperature.
B)taste.
C)touch.
D)vibration.
E)pain.

Question 9

Endorphins can reduce perception of sensations initiated by

A)nociceptors.
B)mechanoreceptors.
C)thermoreceptors.
D)chemoreceptors.
E)proprioceptors.

Question 10

A receptor potential may

A)increase neurotransmitter release.
B)decrease neurotransmitter release.
C)be a hyperpolarization.
D)be a depolarization.
E)All of the answers are correct.

Question 11

Which of the following statements is true about general senses?

A)They are distributed all over the body.
B)They are all mechanoreceptors.
C)Receptors involved in general sensation consist of naked nerve endings.
D)They are located in sense organs.
E)The reception of the stimulus occurs slowly with these receptors.

Question 12

A receptor that contains many mechanically-gated ion channels would function best as a

A)tactile receptor.
B)chemoreceptor.
C)photoceptor
D)thermoreceptor.
E)light receptor.

Question 13

Peripheral adaptation ________ the number of action potentials that reach the CNS.

A)decreases
B)increases
C)stabilizes
D)neutralizes
E)amplifies

Question 14

A mechanoreceptor in the papillary layer of the dermis that responds to fine touch is a

A)tactile (Merkel)disc.
B)root hair plexus.
C)free nerve ending.
D)Ruffini corpuscle.
E)tactile (Meissner)corpuscle.

Question 15

Gustatory receptors are sensitive to dissolved chemicals but insensitive to light.This is due to

A)receptor specificity.
B)accessory cells.
C)the fact that they are interoceptors.
D)receptor potentials.
E)receptor speciation.

Question 16

Examples of sensory stimuli include

A)touch.
B)warmth.
C)pain.
D)vibration.
E)All of the answers are correct.

Question 17

Which of the following can contribute to receptor specificity?

A)the structure of the receptor cell
B)characteristics of the receptor cell membrane
C)accessory cells that function with the receptor
D)accessory structures and tissues that shield the receptors from other stimuli
E)All of the answers are correct.

Question 18

Sensory transduction can involve which of the following?

A)a stimulus altering the permeability of a receptor membrane
B)change in the flow of ions across the sensory membrane
C)the production of a receptor potential
D)inhibition of neurotransmitter release
E)All of the answers are correct.

Question 19

Sensory encoding of the perceived location of a stimulus depends on

A)the frequency of action potentials.
B)which labeled line is active.
C)the specific location of the cortical neuron that is stimulated.
D)the specific sensitivity of the peripheral receptor.
E)the number of receptors stimulated.

Question 20

Central adaptation refers to

A)the decline in activity of peripheral receptors when stimulated.
B)a characteristic of phasic receptors.
C)inhibition of nuclei located along a sensory pathway.
D)increases in conscious perception of a sensory stimulus.
E)a change in motor receptivity of a neuron.

Question 21

For the last few weeks,you have had an odd sensation on your upper thigh.When you touch the naked skin,it feels very strange,like you are touching your skin through layers of cloth.The surrounding area feels normal.Your doctor thinks that this may be related to spinal nerve damage related to a herniated disc.The doctor calls this change in sensation

A)paresthesia.
B)anesthesia.
C)hypesthesia.
D)synesthesia.
E)kinesthesia.

Question 22

Which of the following kinds of information do fine-touch and light-pressure mechanoreceptors provide?

A)location of the stimulus
B)shape of the stimulus
C)texture of the stimulus
D)movement of the stimulus
E)All of the answers are correct.

Question 23

Which of the following is a property of thermoreceptors?

A)involves specialized receptors
B)monitor heat stimuli,not cold
C)found in skin only
D)project to reticular formation
E)cold receptors found around the body in small numbers

Question 24

A fast-adapting tactile receptor that monitors movements across the body surface is a

A)tactile (Merkel)disc.
B)lamellated corpuscle.
C)tactile (Meissner)corpuscle.
D)Ruffini corpuscle.
E)root hair plexus.

Question 25

A very large,fast-adapting tactile receptor that is composed of a single dendrite enclosed by concentric layers of collagen is a

A)Ruffini corpuscle.
B)lamellated (Pacinian)corpuscle.
C)tactile (Meissner)corpuscle.
D)tactile (Merkel)disc.
E)root hair plexus.

Question 26

________ are receptors in the aorta that monitor the blood pressure.

A)Chemoreceptors
B)Nociceptors
C)Baroreceptors
D)Proprioceptors
E)Hair cells

Question 27

Chemoreceptors are located in all of the following except

A)carotid bodies.
B)aortic bodies.
C)the skin.
D)the organs of taste.
E)the organs of smell.

Question 28

Tactile receptors composed of capsules that surround a core of collagen fibers intertwined with dendrites are called

A)Ruffini corpuscles.
B)lamellated corpuscles.
C)tactile (Meissner)corpuscles.
D)tactile discs.
E)root hair plexuses.

Question 29

A sensory receptor characterized peripherally as a free nerve ending which centrally uses glutamate and/or substance P as neurotransmitters would most likely be a

A)chemoreceptor.
B)mechanoreceptor.
C)thermoreceptor.
D)nociceptor.
E)free receptor.

Question 30

If a friend is talking about someone she knows who lost his special senses,you would correct her when you hear her mention ________ because it is not a special sense.

A)smell
B)sight
C)balance
D)cold
E)hearing

Question 31

A highly sensitive tactile receptor composed of dendritic processes of a single myelinated fiber that makes contact with specialized cells of the stratum germinativum (basale)is a

A)lamellated corpuscle.
B)tactile (Meissner)corpuscle.
C)Ruffini corpuscle.
D)tactile (Merkel)disc.
E)root hair plexus.

Question 32

We are constantly bombarded by a variety of stimuli inside and outside of our bodies.Why are we not overwhelmed by sensory information?

A)We do not have receptors for most stimuli.
B)Stimuli are blocked from the receptors by our immune systems.
C)Most stimuli are external to our bodies and we have very few exteroceptors on the outside of the body.
D)A particular receptor type can have different sensitivities to different stimuli.
E)A very tiny percentage of incoming sensory information is received by the cerebral cortex.

Question 33

A tactile receptor composed of highly coiled dendrites that are surrounded by modified Schwann cells and a fibrous capsule is a

A)lamellated corpuscle.
B)Ruffini corpuscle.
C)tactile (Meissner)corpuscle.
D)tactile (Merkel)disc.
E)root hair plexus.

Question 34

Mechanoreceptors might detect which of the following sensations?

A)pressure
B)touch
C)vibration
D)muscle length
E)All of the answers are correct.

Question 35

Bladder fullness is to ________ as blood pH is to ________.

A)nociceptors; thermoreceptors
B)baroreceptors; chemoreceptors
C)baroreceptors; nociceptors
D)chemoreceptors; nociceptors
E)baroreceptors; thermoreceptors

Question 36

Tactile discs are to ________ as tactile corpuscles are to ________.

A)Wilms; Meissner
B)Merkel; Meissner
C)Meissner; Merkel
D)Pacinian; Merkel
E)pain; pressure

Question 37

Mechanoreceptors that respond to changes in blood pressure are called

A)nociceptors.
B)baroreceptors.
C)chemoreceptors.
D)proprioceptors.
E)thermoreceptors.

Question 38

Sensations of burning or aching pain

A)are carried by type A fibers.
B)reach the CNS quickly.
C)cause a generalized activation of the reticular formation and the thalamus.
D)are well localized.
E)are fast adapting.

Question 39

Pain is to ________ as cold is to ________.

A)nociceptors; thermoreceptors
B)baroreceptors; chemoreceptors
C)baroreceptors; nociceptors
D)chemoreceptors; nociceptors
E)baroreceptors; thermoreceptors

Question 40

Receptors that monitor the position of joints belong to the category called

A)nociceptors.
B)chemoreceptors.
C)baroreceptors.
D)proprioceptors.
E)thermoreceptors.

Question 41

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Which structure conducts action potentials directly from a sensory receptor?

A)1
B)2
C)3
D)5
E)7

Question 42

Which ascending tract carries the sensations for fine touch and vibration?

A)corticobulbar
B)corticospinal
C)posterior (dorsal)column
D)spinothalamic
E)spinobulbar

Question 43

Neurons from the fasciculus gracilis

A)relay information directly to the cerebrum.
B)decussate before entering the medial lemniscus.
C)relay sensory information to the ipsilateral cerebral hemisphere.
D)carry both crude and fine touch.
E)process proprioception.

Question 44

Your uncle was just diagnosed with a heart attack.One of his major symptoms is left arm pain.You are not surprised because you are familiar with the phenomenon of ________ pain.

A)referred
B)phantom
C)psychogenic
D)somatic
E)neurogenic

Question 45

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Identify the structure labeled "5."

A)thalamus
B)cerebral cortex
C)primary motor cortex
D)primary sensory cortex
E)autonomic ganglion

Question 46

Which neuron delivers sensations to the CNS?

A)first-order
B)second-order
C)third-order
D)fourth-order
E)sensory receptor

Question 47

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Identify the neuron labeled "3."

A)lower motor neuron
B)upper motor neuron
C)first-order neuron
D)second-order neuron
E)ganglionic neuron

Question 48

Which ascending tract carries the sensations for fine touch and vibration?

A)corticobulbar
B)corticospinal
C)posterior (dorsal)column
D)spinothalamic
E)spinocerebellar

Question 49

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Where in the spinal cord is the structure labeled "2" located?

A)anterior gray horns
B)dorsal root ganglion
C)anterior white column
D)anterior median fissure
E)posterior white column

Question 50

What loss would result from cutting through the medial lemniscus on the right side?

A)loss of pain sensation on the left side of the body
B)loss of pain sensation on the right side of the body
C)loss of fine touch sensation on the left side of the body
D)loss of fine touch sensation on the right side of the body
E)complete hemiplegia (paralysis)on the left side of the body

Question 51

Stimulation of a neuron that terminates in the superior region of the left postcentral gyrus would produce

A)a sensation in the right leg.
B)a sensation in the lips.
C)a muscle twitch in the right leg.
D)a muscle twitch in the lips.
E)both sensations and muscle twitches in the right leg.

Question 52

The spinal tract that carries sensations from proprioceptors to the CNS is the

A)fasciculus gracilis.
B)fasciculus cuneatus.
C)spinocerebellar.
D)lateral spinothalamic.
E)anterior spinothalamic.

Question 53

We can localize sensations that originate in different areas of the body because

A)sensory neurons carry only one modality.
B)sensory neurons from specific body regions project to specific cortical regions.
C)incoming sensory information is first processed by the thalamus.
D)different types of sensory receptors produce action potentials of different sizes and shapes.
E)of the many types of tactile receptors.

Question 54

The afferent neuron that carries the sensation to the CNS is a ________ neuron.

A)receptor
B)first-order
C)second-order
D)third-order
E)fourth-order

Question 55

Each of the following is an ascending tract in the spinal cord except the

A)fasciculus gracilis.
B)fasciculus cuneatus.
C)posterior spinocerebellar.
D)reticulospinal tract.
E)anterior spinothalamic.

Question 56

The spinal tract that relays information concerning pain and temperature to the CNS is the

A)fasciculus gracilis.
B)fasciculus cuneatus.
C)posterior spinocerebellar.
D)lateral spinothalamic.
E)anterior spinothalamic.

Question 57

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Which of the following is true regarding the structure labeled "6"?
1)The synapse occurs between motor neurons.
2)The sensations may be filtered out.
3)The third-order neuron projects to the primary sensory cortex.
4)The third-order neuron's axon is identified.

A)1 and 4
B)2 only
C)3 only
D)3 and 4
E)1 and 3

Question 58

The spinal tract that relays information concerning crude touch and pressure to the CNS is the

A)fasciculus gracilis.
B)fasciculus cuneatus.
C)posterior spinocerebellar.
D)lateral spinothalamic.
E)anterior spinothalamic.

Question 59

Figure 15-1 Spinothalamic Tracts
Use Figure 15-1 to answer the following questions:
Identify the neuron labeled " 1."

A)lower motor neuron
B)upper motor neuron
C)first-order neuron
D)second-order neuron
E)ganglionic neuron

Question 60

Thalamic neurons that project to the primary sensory cortex are ________ neurons.

A)receptor
B)first-order
C)second-order
D)third-order
E)fourth-order

Question 61

The descending spinal tract that crosses to the opposite side of the body within the cord is the ________ tract.

A)lateral corticospinal
B)anterior corticospinal
C)rubrospinal
D)reticulospinal
E)vestibulospinal

Question 62

The spinal tract that unconsciously maintains balance and muscle tone is the ________ tract.

A)lateral corticospinal
B)anterior corticospinal
C)rubrospinal
D)reticulospinal
E)vestibulospinal

Question 63

Destruction of or damage to a lower motor neuron in the somatic nervous system produces

A)the inability to localize a stimulus.
B)a subconscious response to a stimulation.
C)flaccid paralysis of its muscle fibers (motor unit).
D)a stimulation of the innervated muscle.
E)contractile paralysis of its motor unit.

Question 64

Upper motor neurons of the corticospinal tract synapse with neurons in

A)autonomic ganglia.
B)the anterior gray horns of the spinal cord.
C)the spinothalamic tract.
D)the lateral gray horns of the spinal cord.
E)the dorsal root ganglia.

Question 65

The descending spinal tract that crosses to the opposite side of the body within the medulla oblongata is the ________ tract.

A)lateral corticospinal
B)anterior corticospinal
C)rubrospinal
D)reticulospinal
E)vestibulospinal

Question 66

The medial pathway that controls involuntary movements of head,neck,and arm position in response to sudden visual and auditory stimuli is the ________ tract.

A)lateral corticospinal
B)tectospinal
C)rubrospinal
D)reticulospinal
E)vestibulospinal

Question 67

Descending (motor)pathways always involve at least ________ motor neuron(s).

A)one
B)two
C)three
D)four
E)spinal

Question 68

The corticospinal system is often referred to as the

A)red nucleus.
B)reticular formation.
C)spinothalamic tracts.
D)pyramidal system.
E)medullary centers.

Question 69

The cerebellum relies on information from

A)the eyes.
B)the inner ear as movements are underway.
C)proprioceptive sensations.
D)motor commands from upper motor neurons.
E)All of the answers are correct.

Question 70

The ________ tract provides subconscious regulation of balance and muscle tone and is part of the ________ pathway.

A)tectospinal; lateral
B)rubrospinal; lateral
C)reticulospinal; medial
D)vestibulospinal; medial
E)corticobulbar; medial

Question 71

Based on the motor homunculus,which of the following body regions has the fewest number of motor units involved?

A)tongue
B)face
C)hands
D)back trunk

Question 72

Axons that decussate between the pyramids of the medulla oblongata belong to the ________ tracts.

A)anterior corticospinal
B)lateral corticospinal
C)vestibulospinal
D)reticulospinal
E)rubrospinal

Question 73

The pyramids on the ventral surface of the medulla oblongata are formed by fibers of the ________ tracts.

A)corticospinal
B)corticobulbar
C)reticulospinal
D)vestibulospinal
E)tectospinal

Question 74

The spinal tract that normally plays a role in the subconscious regulation of the muscles of the arms is the ________ tract.

A)lateral corticospinal
B)anterior corticospinal
C)rubrospinal
D)reticulospinal
E)vestibulospinal

Question 75

The area of the motor cortex that is devoted to a particular region of the body is proportional to the

A)size of the body area.
B)distance of the body area from the brain.
C)number of motor units in that region.
D)number of sensory receptors in the area of the body.
E)size of the nerves that serve the area of the body.

Question 76

The pyramidal system provides

A)voluntary control over skeletal muscles.
B)voluntary control over smooth muscles.
C)involuntary control over skeletal muscles.
D)involuntary control over smooth muscles.
E)involuntary control over cardiac muscle.

Question 77

Axons of the corticobulbar tract terminate in the

A)sensory neurons.
B)somatic motor neurons in the spinal cord.
C)autonomic motor neurons in the spinal cord.
D)motor nuclei of cranial nerves.
E)nuclei in the thalamus.

Question 78

The ________ tract provides subconscious regulation of upper limb muscle tone and movement and is part of the ________ pathway.

A)tectospinal; lateral
B)rubrospinal; lateral
C)reticulospinal; medial
D)vestibulospinal; lateral
E)corticobulbar; medial

Question 79

Identify the type of information that travels along the structure labeled "2."

A)motor commands to skeletal muscles
B)proprioception to the cerebral cortex
C)fine touch to the cerebral cortex
D)pressure and touch sensations
E)visceral motor commands to smooth muscle

Question 80

The cerebellum

A)functions to maintain proper posture and equilibrium.
B)receives input from the motor cortex and basal ganglia.
C)compares intended movement to actual movement.
D)if damaged leads to uncoordinated and jerky movements.
E)has all of these characteristics.