Download Chapter 15 - FacultyWeb

If transduction does not occur, what do you perceive
about a stimulus?
1. It is stronger than usual.
2. It is as though the stimulus did not take
place and you feel nothing.
3. UV light was not converted into part of the
visible spectrum.
4. It is weaker than usual.
Receptor A has a circular receptive field with a
diameter of 2.5 cm. Receptor B has a circular
receptive field of 7.0 cm in diameter. Which receptor
allows you to more precisely localize a stimulus?
1. Receptor A
2. They would provide the same
precision of sensory information
3. Receptor B
4. It would depend upon the location of
the receptors
Distinguishing facts concerning tonic receptors
include all of the following except:
1. Tonic receptors are always active.
2. The frequency of action potential generation
indicates the background level of stimulation.
3. Tonic receptors are active for a short time
whenever a change occurs in conditions
monitored.
4. When a stimulus increases or decreases, the
rate of action potential generation changes.
Which of the following has occurred if you no longer
notice the smell of a dirty cat litter box?
1.
2.
3.
4.
Peripheral adaptation
Anosmia
Sensory coding
Central adaptation
Which type of general sensory receptor is correctly
paired with its function?
1. Mechanoreceptor/detect changes in
temperature
2. Chemoreceptors/sensitive to stimuli that
distort their cell membranes
3. Thermoreceptors/detect changes in
concentration of specific chemicals or
compounds
4. None of these is correctly paired
Nociceptors are _____ receptors. To what
categories of sensations are nociceptors sensitive?
1.
2.
3.
4.
Thermoreceptors/extremes of temperature
and changes in vibration
Pain/extremes of temperature, mechanical
damage and chemicals released from
injured cells
Pain/changes in pressure or stretch in
muscles
Chemoreceptors/changes in concentration of
chemicals or compounds
A patient who describes their pain as “prickling” is
experiencing pain sensations carried by ____.
1.
2.
3.
4.
Substance P
Unmyelinated Type C fibers
Glutamate
Myelinated Type A fibers
What type of fibers carry information about itch and
tickle sensations?
1.
2.
3.
4.
Unmyelinated Type C fibers
Myelinated Type A fibers
All nociceptors
None of these is correct
Which type of tactile receptor gives you the most
information about location, size, and shape of the
source of stimulation?
1.
2.
3.
4.
Root hair plexus
Free nerve endings
Tactile (Merkel’s) discs
Lamellated (Pacinian) corpuscles
Someone is gently brushing your arm with a feather.
Which type of receptor is stimulated?
1.
2.
3.
4.
Tactile (Meissner’s) corpuscles
Tactile (Merkel’s) discs
Root hair plexuses
All of the above are correct
Baroreceptors are located in all of the following
locations, except _____?
1.
2.
3.
4.
Blood vessels
Respiratory tract
Carotid bodies
Digestive tract
What would happen if the information from
proprioceptors in your legs were blocked from
reaching the CNS?
1. You would not experience pain sensations
from your legs.
2. Your lower limb movements would be
uncoordinated.
3. You wouldn’t know position or degree of
stretch in tendons of your legs.
4. 2 and 3 are correct.
Which of the following is incorrect concerning
chemoreceptors?
1.
2.
3.
4.
They exhibit peripheral adaptation over a few
seconds.
We are not consciously aware of the sensations
they provide.
Information is routed through the cerebral cortex for
control of respiratory and cardiovascular function.
Chemoreceptive neurons are located in the carotid
bodies and aortic bodies.
If a sensation is to reach your conscious awareness,
there must be a synapse with a ____ in the ____?
1.
2.
3.
4.
First-order neuron/thalamus
Second-order neuron/primary sensory cortex
First-order neuron/dorsal root ganglion
Third-order neuron/thalamus
As a result of pressure on her spinal cord, Jill
cannot feel touch or pressure on her lower limbs.
Which spinal tract is being compressed?
1.
2.
3.
4.
Fasciculus cuneatus
Fasciculus gracilis
Lateral spinothalamic tract
Anterior spinothalamic tract
The ____ carries sensation of highly localized
(fine) touch, while the ____ provides conscious
sensations of poorly localized (crude) touch?
1.
2.
3.
4.
Posterior column pathway/anterior spinothalamic tract
Fasciculus gracilis/fasciculus cuneatus
Spinocerebellar pathway/lateral spinothalamic tracts
Spinothalamic pathway/spinocerebellar pathway
Which spinal tract carries action potentials
generated by nociceptors?
1.
2.
3.
4.
Fasciculus cuneatus
Fasciculus gracilis
Lateral spinothalamic tract
Anterior spinothalamic tract
What is unusual about the posterior spinocerebellar
tracts when compared with other ascending pathways?
1.
2.
3.
4.
The decussation of axons in the medulla innervate
motor neurons on the opposite side of the body.
Axons enter the posterior spinothalamic tract on the
same side of the body.
They are the only tracts to carry information about
referred pain.
They carry information along visceral sensory
pathways.
For what anatomical reason does the left side
of the brain control motor function on the right
side of the body?
1. Motor function is controlled by a system of
two neurons
2. Motor function is controlled by cranial reflexes
3. The motor area devoted to a particular area
becomes larger
4. Decussation of axons
An injury involving the superior portion of the motor
cortex affects which region of the body?
1.
2.
3.
4.
Upper portion of the lower limb
Upper limb
Lower leg and foot
Both 1 and 2
Why does the motor homunculus depict the hands,
face, and tongue hugely out of proportion?
1. The brain area devoted to using those
regions is vast.
2. More motor units are needed for fine
control of those areas.
3. The cortical areas mapped for
controlling those areas overlap with the
sensory regions controlling those areas.
4. 1 and 3 are correct.
The medial pathway controls ______, whereas the
lateral pathway controls _____.
1.
2.
3.
4.
Gross movements of the trunk and proximal limb
muscles/distal limb muscles and precise movement
Background patterns of movement/transmits motor
impulses from the cerebrum to the spinal cord
Subconscious control of balance and muscle
tone/subconscious control of reflex activity
None of these is correct
Parkinson’s disease manifests which of the
following abnormalities?
1.
2.
3.
4.
The motor cortex ceases receiving messages from
sensory neurons.
Excitatory neurons in the basal nuclei become more
active, leading to faulty control of voluntary
movements.
Axons that synapse in the thalamus no longer
convey messages to the motor cortex.
GABA is released by neurons in excessive amounts.
Which of the following motor pathways remains
uncrossed along its length?
1.
2.
3.
4.
Vestibulospinal tract
Tectospinal tract
Anterior corticospinal tract
Lateral corticospinal tract
The cerebellum monitors proprioceptive
information for which two senses?
1.
2.
3.
4.
Visual and hearing
Hearing and postural information
Taste and smell
Vestibular and visual
Why is cerebellar control over well-practiced
movements, such as swinging a baseball bat,
important?
1. Voluntary movements begin with activation
of far fewer motor units than necessary.
2. Concentrating on voluntary control using
the motor cortex disrupts the pattern and
rhythm.
3. Patterns of movement are unchanging.
4. Both 1 and 2.