Transcript File - jj-sct

CAMPBELL
BIOLOGY
TENTH
EDITION
Reece • Urry • Cain • Wasserman • Minorsky • Jackson
49
Nervous
Systems
Clicker Questions by
Roberta Batorsky
© 2014 Pearson Education, Inc.
Which glial cells have a capacity to act as stem cells for
neurons?
a) Schwann cells
b) oligodendrocytes
c) microglia
d) astrocytes
e) ependymal cells
© 2014 Pearson Education, Inc.
Which glial cells have a capacity to act as stem cells for
neurons?
a) Schwann cells
b) oligodendrocytes
c) microglia
d) astrocytes
e) ependymal cells
© 2014 Pearson Education, Inc.
Where in the spinal cord are myelinated axons most
likely to be found, and what trait of these axons makes
their myelination important?
a) lining the central canal; these axons are relatively
wide
b) inner layer; these axons are relatively long
c) inner layer; these axons are relatively wide
d) outer layer; these axons are relatively short
e) outer layer; these axons are relatively long
© 2014 Pearson Education, Inc.
Where in the spinal cord are myelinated axons most
likely to be found, and what trait of these axons makes
their myelination important?
a) lining the central canal; these axons are relatively
wide
b) inner layer; these axons are relatively long
c) inner layer; these axons are relatively wide
d) outer layer; these axons are relatively short
e) outer layer; these axons are relatively long
© 2014 Pearson Education, Inc.
During human embryonic/fetal development, which part
of the CNS undergoes the largest increase
in mass?
a) forebrain
b) midbrain
c) hindbrain
d) spinal cord
e) cerebellum
© 2014 Pearson Education, Inc.
During human embryonic/fetal development, which part
of the CNS undergoes the largest increase
in mass?
a) forebrain
b) midbrain
c) hindbrain
d) spinal cord
e) cerebellum
© 2014 Pearson Education, Inc.
Which of these can lead to activation of the brain’s reward
system?
1. decreased inhibition of the ventral tegmental area (VTA)
neurons
2. increased dopamine secretion by VTA neurons
3. blocked dopamine reuptake from synaptic clefts of the
reward pathway
4. decreased dopamine secretion by VTA neurons
5. increased dopamine reuptake from synaptic clefts of
reward pathway
a) 1 or 2
b) 1 or 4
c) 2 or 5
d) 1, 2, or 3
e) 1, 4, or 5
© 2014 Pearson Education, Inc.
Which of these can lead to activation of the brain’s reward
system?
1. decreased inhibition of the ventral tegmental area (VTA)
neurons
2. increased dopamine secretion by VTA neurons
3. blocked dopamine reuptake from synaptic clefts of the
reward pathway
4. decreased dopamine secretion by VTA neurons
5. increased dopamine reuptake from synaptic clefts of
reward pathway
a) 1 or 2
b) 1 or 4
c) 2 or 5
d) 1, 2, or 3
e) 1, 4, or 5
© 2014 Pearson Education, Inc.
Inebriated people have difficulty touching their noses
with their eyes closed. Which part of the brain has been
most impaired to bring about this difficulty?
a) hypothalamus
b) cerebellum
c) cerebral cortex
d) Broca’s area
e) limbic system
© 2014 Pearson Education, Inc.
Inebriated people have difficulty touching their noses
with their eyes closed. Which part of the brain has been
most impaired to bring about this difficulty?
a) hypothalamus
b) cerebellum
c) cerebral cortex
d) Broca’s area
e) limbic system
© 2014 Pearson Education, Inc.
What may occur to interneurons in circuits that are not
accessed often?
a) the addition of synapses to improve accessibility
b) the removal of synapses to improve overall
cognition
c) the addition of new neurons by stem cells to make
access easier
d) the myelination of such neurons to improve their
speed
e) the demyelination of such neurons to improve their
sensitivity
© 2014 Pearson Education, Inc.
What may occur to interneurons in circuits that are not
accessed often?
a) the addition of synapses to improve accessibility
b) the removal of synapses to improve overall
cognition
c) the addition of new neurons by stem cells to make
access easier
d) the myelination of such neurons to improve their
speed
e) the demyelination of such neurons to improve their
sensitivity
© 2014 Pearson Education, Inc.
Arousal and sleep are controlled by the part of the
brain called the
a) hypothalamus.
b) medulla oblongata.
c) cerebrum.
d) amygdala.
e) reticular formation.
© 2014 Pearson Education, Inc.
Arousal and sleep are controlled by the part of the
brain called the
a) hypothalamus.
b) medulla oblongata.
c) cerebrum.
d) amygdala.
e) reticular formation.
© 2014 Pearson Education, Inc.
In PET (positron-emission tomography)
scanning of the brain, scientists and physicians
inject radioactive glucose and detect activity in a
specific brain region by changes in the local
____________concentration.
a) blood
b) hydrogen
c) oxygen
d) nitrogen
e) DNA
© 2014 Pearson Education, Inc.
In PET (positron-emission tomography)
scanning of the brain, scientists and physicians
inject radioactive glucose and detect activity in a
specific brain region by changes in the local
____________concentration.
a) blood
b) hydrogen
c) oxygen
d) nitrogen
e) DNA
© 2014 Pearson Education, Inc.
Which is an incorrect statement about the
somatosensory and motor cortex?
a) Neurons are arranged according to the part of the
body that generates the sensory input.
b) Neurons are arranged according to the part of the
body that receives the motor commands.
c) The cortical surface area devoted to each body part
is proportional to the size of the part.
d) Surface area correlates with the extent of neuronal
control needed.
e) The surface area of the motor cortex devoted to the
face is larger than that devoted to the trunk.
© 2014 Pearson Education, Inc.
Which is an incorrect statement about the
somatosensory and motor cortex?
a) Neurons are arranged according to the part of the
body that generates the sensory input.
b) Neurons are arranged according to the part of the
body that receives the motor commands.
c) The cortical surface area devoted to each body
part is proportional to the size of the part.
d) Surface area correlates with the extent of neuronal
control needed.
e) The surface area of the motor cortex devoted to the
face is larger than that devoted to the trunk.
© 2014 Pearson Education, Inc.
The establishment of differences in cortical
hemisphere function is called
a) specialization.
b) lateralization.
c) the “split-brain effect.”
d) hemispheric dominance.
© 2014 Pearson Education, Inc.
The establishment of differences in cortical
hemisphere function is called
a) specialization.
b) lateralization.
c) the “split-brain effect.”
d) hemispheric dominance.
© 2014 Pearson Education, Inc.
Scientific Skills Exercises
Researchers surgically removed the SCN from wild-type
and τ hamsters. Several weeks later, each of these
hamsters received a transplant of an SCN from a
hamster of the opposite genotype. These transplants
restored rhythmic activity in 80% of the hamsters.
© 2014 Pearson Education, Inc.
For hamsters in which an SCN transplant restored a
circadian rhythm, the researchers measured the
circadian period. The results are shown in the graph.
Each red line represents the change in the measured
period for an individual hamster.
© 2014 Pearson Education, Inc.
In a controlled experiment, researchers manipulate
one variable at a time. What was the experimental
variable in this study?
a) the genotype of the host tissue
b) whether the hamster's original SCN was removed
c) whether the SCN was part of the transplanted
tissue
d) the genotype of the transplanted tissue
© 2014 Pearson Education, Inc.
In a controlled experiment, researchers manipulate
one variable at a time. What was the experimental
variable in this study?
a) the genotype of the host tissue
b) whether the hamster's original SCN was removed
c) whether the SCN was part of the transplanted
tissue
d) the genotype of the transplanted tissue
© 2014 Pearson Education, Inc.
Why did the researchers use more than one hamster
for each procedure?
a) to assess the variability of circadian rhythms across
different individuals
b) to assess whether the SCN or some other part of the
hypothalamus is responsible for circadian rhythm
c) to assess whether the differences in cycle period
before and after transplant were greater than the
variation in cycle period from animal to animal
d) to determine whether the results were consistent
regardless of the sex of the animals
© 2014 Pearson Education, Inc.
Why did the researchers use more than one hamster
for each procedure?
a) to assess the variability of circadian rhythms across
different individuals
b) to assess whether the SCN or some other part of the
hypothalamus is responsible for circadian rhythm
c) to assess whether the differences in cycle period
before and after transplant were greater than the
variation in cycle period from animal to animal
d) to determine whether the results were consistent
regardless of the sex of the animals
© 2014 Pearson Education, Inc.
What traits of the individual hamsters would likely have
been controlled across the treatment groups?
a) age and sex
b) age only
c) sex only
d) genotype
© 2014 Pearson Education, Inc.
What traits of the individual hamsters would likely have
been controlled across the treatment groups?
a) age and sex
b) age only
c) sex only
d) genotype
© 2014 Pearson Education, Inc.
For the wild-type hamsters that received τ SCN
transplants, what would have been an appropriate
control?
a) transplant the entire hypothalamus from a τ hamster
to a wild-type hamster
b) transplant the SCN from one τ hamster to
another τ hamster
c) surgically expose the brain of a τ hamster without
removing the SCN
d) transplant the SCN from one wild-type hamster to
another wild-type hamster
© 2014 Pearson Education, Inc.
For the wild-type hamsters that received τ SCN
transplants, what would have been an appropriate
control?
a) transplant the entire hypothalamus from a τ hamster
to a wild-type hamster
b) transplant the SCN from one τ hamster to
another τ hamster
c) surgically expose the brain of a τ hamster without
removing the SCN
d) transplant the SCN from one wild-type hamster to
another wild-type hamster
© 2014 Pearson Education, Inc.
What general trends does the graph reveal about the
period of the circadian rhythm in transplant recipients?
a) It was similar to that of the donor in wild-type
hamsters but similar to that of the recipient
in τ hamsters.
b) It was determined by the genotype of the recipient.
c) It was similar to that of the donor, whether the
recipient was wild-type or τ mutant.
d) It was similar to that of the donor in τ hamsters but
similar to that of the recipient in wild-type hamsters.
© 2014 Pearson Education, Inc.
What general trends does the graph reveal about the
period of the circadian rhythm in transplant recipients?
a) It was similar to that of the donor in wild-type
hamsters but similar to that of the recipient
in τ hamsters.
b) It was determined by the genotype of the recipient.
c) It was similar to that of the donor, whether the
recipient was wild-type or τ mutant.
d) It was similar to that of the donor in τ hamsters but
similar to that of the recipient in wild-type hamsters.
© 2014 Pearson Education, Inc.
What can you conclude about the role of the SCN in
determining the period of the circadian rhythm?
a) The SCN determines the period of the circadian
rhythm in wild-type hamsters but not τ hamsters.
b) The SCN determines the period of the circadian
rhythm in τ hamsters but not wild-type hamsters.
c) The SCN does not determine the period of the
circadian rhythm.
d) The SCN determines the period of the circadian
rhythm.
© 2014 Pearson Education, Inc.
What can you conclude about the role of the SCN in
determining the period of the circadian rhythm?
a) The SCN determines the period of the circadian
rhythm in wild-type hamsters but not τ hamsters.
b) The SCN determines the period of the circadian
rhythm in τ hamsters but not wild-type hamsters.
c) The SCN does not determine the period of the
circadian rhythm.
d) The SCN determines the period of the
circadian rhythm.
© 2014 Pearson Education, Inc.
In 20% of the hamsters, there was no restoration of
rhythmic activity following the SCN transplant. Can you be
confident of your conclusion about the role of the SCN
based on data from 80% of the hamsters? Why or why
not?
a) No. The most likely explanation is that the SCN does not
control the circadian rhythm in hamsters.
b) Yes. The data from 80% of the hamsters are very
consistent. In the other 20%, the transplanted SCN may
not have established functional connections with the
recipient's brain.
c) No. A failure rate of 20% is much too high in any
experiment.
d) Yes. Because 80% is much higher than 20%, the result is
reliable.
© 2014 Pearson Education, Inc.
In 20% of the hamsters, there was no restoration of
rhythmic activity following the SCN transplant. Can you be
confident of your conclusion about the role of the SCN
based on data from 80% of the hamsters? Why or why
not?
a) No. The most likely explanation is that the SCN does not
control the circadian rhythm in hamsters.
b) Yes. The data from 80% of the hamsters are very
consistent. In the other 20%, the transplanted SCN
may not have established functional connections with
the recipient's brain.
c) No. A failure rate of 20% is much too high in any
experiment.
d) Yes. Because 80% is much higher than 20%, the result is
reliable.
© 2014 Pearson Education, Inc.
Suppose researchers identified a mutation that caused
hamsters to have no rhythmic activity. Also suppose you
transplanted the SCN of wild-type hamsters into hamsters
with this mutation. What result would you expect from this
experiment, assuming that the SCN determines the period
of the circadian rhythm?
a) The recipients would have rhythmic activity with a variety
of periods ranging from 20 to 24 hours.
b) The recipients would have rhythmic activity with a
period of about 24 hours.
c) The recipients would have no rhythmic activity.
d) The recipients would have rhythmic activity with a period
of about 20 hours.
© 2014 Pearson Education, Inc.
Suppose researchers identified a mutation that caused
hamsters to have no rhythmic activity. Also suppose you
transplanted the SCN of wild-type hamsters into hamsters
with this mutation. What result would you expect from this
experiment, assuming that the SCN determines the period
of the circadian rhythm?
a) The recipients would have rhythmic activity with a variety
of periods ranging from 20 to 24 hours.
b) The recipients would have rhythmic activity with a
period of about 24 hours.
c) The recipients would have no rhythmic activity.
d) The recipients would have rhythmic activity with a period
of about 20 hours.
© 2014 Pearson Education, Inc.
What result would you expect if you transplanted the
SCN of τ hamsters into no-rhythmic-activity mutants
a) The recipients would have rhythmic activity with a
variety of periods ranging from 20 to 24 hours.
b) The recipients would have no rhythmic activity.
c) The recipients would have rhythmic activity with a
period of about 24 hours.
d) The recipients would have rhythmic activity with a
period of about 20 hours.
© 2014 Pearson Education, Inc.
What result would you expect if you transplanted the
SCN of τ hamsters into no-rhythmic-activity mutants
a) The recipients would have rhythmic activity with a
variety of periods ranging from 20 to 24 hours.
b) The recipients would have no rhythmic activity.
c) The recipients would have rhythmic activity with a
period of about 24 hours.
d) The recipients would have rhythmic activity with a
period of about 20 hours.
© 2014 Pearson Education, Inc.