1. CAMPBELL BIOLOGY Reece Urry Cain Wasserman Minorsky Jackson © 2014 Pearson Education, Inc. TENTH EDITION Clicker Questions by Roberta Batorsky 49 Nervous Systems

2. © 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

3. © 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

4. © 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

5. © 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

6. © 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

7. © 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

8. © 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

9. © 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

10. © 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

11. © 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

12. © 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

13. © 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

14. © 2014 Pearson Education, Inc. a) hypothalamus. b) medulla oblongata. c) cerebrum. d) amygdala. e) reticular formation. Arousal and sleep are controlled by the part of the brain called the

15. © 2014 Pearson Education, Inc. a) hypothalamus. b) medulla oblongata. c) cerebrum. d) amygdala. e) reticular formation. Arousal and sleep are controlled by the part of the brain called the

16. © 2014 Pearson Education, Inc. a) blood b) hydrogen c) oxygen d) nitrogen e) DNA 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.

17. © 2014 Pearson Education, Inc. a) blood b) hydrogen c) oxygen d) nitrogen e) DNA 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.

18. © 2014 Pearson Education, Inc. 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. Which is an incorrect statement about the somatosensory and motor cortex?

19. © 2014 Pearson Education, Inc. 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. Which is an incorrect statement about the somatosensory and motor cortex?

20. © 2014 Pearson Education, Inc. a) specialization. b) lateralization. c) the “split-brain effect.” d) hemispheric dominance. The establishment of differences in cortical hemisphere function is called

21. © 2014 Pearson Education, Inc. a) specialization. b) lateralization. c) the “split-brain effect.” d) hemispheric dominance. The establishment of differences in cortical hemisphere function is called

22. © 2014 Pearson Education, Inc. 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. Scientific Skills Exercises

23. © 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.

24. © 2014 Pearson Education, Inc. 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 In a controlled experiment, researchers manipulate one variable at a time. What was the experimental variable in this study?

25. © 2014 Pearson Education, Inc. 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 In a controlled experiment, researchers manipulate one variable at a time. What was the experimental variable in this study?

26. © 2014 Pearson Education, Inc. 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 Why did the researchers use more than one hamster for each procedure?

27. © 2014 Pearson Education, Inc. 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 Why did the researchers use more than one hamster for each procedure?

28. © 2014 Pearson Education, Inc. a) age and sex b) age only c)sex only d) genotype What traits of the individual hamsters would likely have been controlled across the treatment groups?

29. © 2014 Pearson Education, Inc. a) age and sex b) age only c)sex only d) genotype What traits of the individual hamsters would likely have been controlled across the treatment groups?

30. © 2014 Pearson Education, Inc. 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 For the wild-type hamsters that received τ SCN transplants, what would have been an appropriate control?

31. © 2014 Pearson Education, Inc. 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 For the wild-type hamsters that received τ SCN transplants, what would have been an appropriate control?

32. © 2014 Pearson Education, Inc. 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. What general trends does the graph reveal about the period of the circadian rhythm in transplant recipients?

33. © 2014 Pearson Education, Inc. 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. What general trends does the graph reveal about the period of the circadian rhythm in transplant recipients?

34. © 2014 Pearson Education, Inc. 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. What can you conclude about the role of the SCN in determining the period of the circadian rhythm?

35. © 2014 Pearson Education, Inc. 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. What can you conclude about the role of the SCN in determining the period of the circadian rhythm?

36. © 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.

37. © 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.

38. © 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.

39. © 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.

40. © 2014 Pearson Education, Inc. 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. What result would you expect if you transplanted the SCN of τ hamsters into no-rhythmic-activity mutants

41. © 2014 Pearson Education, Inc. 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. What result would you expect if you transplanted the SCN of τ hamsters into no-rhythmic-activity mutants