Ch. 15

Question 1

1. Which of the following statements about the features of a nervous system is false?
   a. The transmission rate is relatively fast.
   b. Neurotransmitter release takes place throughout the body via the blood.
   c. Neurons form highly discrete lines of communication.
   d. Action potential signals do not degrade over distance.
   e. In the PNS, a nerve consists of the axons of multiple neurons bundled together.

Answer 1

B

Question 2

2. Interneurons are located in
   a. the central nervous system.
   b. the peripheral nervous system.
   c. the somatic system.
   d. the autonomic system.
   e. both the peripheral and central nervous systems.

Answer 2

A

Question 3

3. Which of the following is not a general feature of a nervous system?
   a. Interneurons are collected into integrated areas at one end of the body rather than randomly dispersed.
   b. Neurons are organized in circuits in such a way that they can elicit a coordinated, adaptive response of effectors.
   c. Sensory receptor cells transform environmental stimuli into electrical signals.
   d. Central interneurons integrate signals from sensory receptors and other signals arising within the animal, generating an integrated pattern of impulses.
   e. Motor commands are sent out from the CNS to effectors.

Answer 3

A

Question 4

4. Which of the following is the effector in the startle response of the cockroach?
   a. Movement of filiform hair receptors
   b. Action potentials in the giant interneuron
   c. A depolarization at the metathoracic ganglion
   d. Contraction of the hind leg muscle
   e. A train of action potentials produced by the leg motor neuron.

Answer 4

D

Question 5

5. Which of the following about sponges is false?
   a. They do not have neurons or nervous systems.
   b. They have neurons but no organized nervous systems.
   c. They possess genes for many of the proteins that make up synaptic structures.
   d. They do not have organs.
   e. They do not have organized tissues.

Answer 5

B

Question 6

6. In an arthropod, the bundle of nerve axons located within a ganglion is called a
   a. nerve.
   b. connective.
   c. sheaf.
   d. neuropile.
   e. tract.

Answer 6

E

Question 7

7. A structural organization in which integrating neurons are all collected into central integrating areas rather than being randomly dispersed is referred to as
   a. cephalization.
   b. centralization.
   c. centrification.
   d. a scent-based communication system.
   e. dorsal root ganglia.

Answer 7

B

Question 8

8. A connective is a bundle of
   a. nerve axons.
   b. nerve axons in the PNS.
   c. axons within a ganglion.
   d. nerve axons between ganglia in the CNS.
   e. axons between the right and left sides of a bilaterally symmetrical ganglion.

Answer 8

D

Question 9

10. In the vertebrate PNS, collections of neuronal cell bodies associated with peripheral nerves are called
    a. afferent neurons.
    b. central ganglia.
    c. peripheral ganglia.
    d. a tract.
    e. a commissure.

Answer 9

C

Question 10

14. Which of the following is not one of the principles of functional organization of the vertebrate brain?
    a. Size matters.
    b. Brains have maps.
    c. The expansion of the forebrain is a recorded event in vertebrate brain evolution.
    d. Brain function is somewhat localized.
    e. Neural circuits are plastic.

Answer 10

C

Question 11

15. A map of the body projected to a brain area is called a
    a. somatotopic map.
    b. sensory homunculus.
    c. motor homunculus.
    d. localization-of-function map.
    e. functional neuroimage.

Answer 11

A

Question 12

16. Which of the following statements regarding the brain is false?
    a. Primate brains perform more complex integration compared to insect brains.
    b. Primate brains have a larger cerebral cortex compared to amphibian brains.
    c. Generally, the larger the cerebral cortex, the more the processing capability of the brain.
    d. Primate brains are more evolved compared to the brains of fish.
    e. All of the statements are true; none is false.

Answer 12

D

Question 13

17. Which of the following areas has the most sensory neurons per unit area of epidermis?
    a. Scalp
    b. Upper arm
    c. Lips
    d. Ring finger
    e. Elbow

Answer 13

C

Question 14

21. Which of the following is not under autonomic control?
    a. Exocrine glands
    b. Adrenal medullary glands
    c. Brown adipose tissue of mammals
    d. Skeletal muscle
    e. The pacemaker region of the heart

Answer 14

D

Question 15

27. The peripheral synapses between the first and second neurons in the sympathetic and parasympathetic divisions are located within clusters of neuronal cell bodies called ________ ganglia.
    a. pathetic
    b. enteric
    c. peripheral
    d. central
    e. autonomic

Answer 15

E

Question 16

28. The nerve that runs from the paravertebral ganglia to the heart would be termed a(n) _______ neuron.
    a. sympathetic postganglionic
    b. parasympathetic postganglionic
    c. sympathetic preganglionic
    d. parasympathetic preganglionic
    e. autonomic ganglionic

Answer 16

A

Question 17

29. Which of the following would occur if epinephrine/norepinephrine were added to the paravertebral ganglia in the upper thoracic area?
    a. Acceleration of heart rate
    b. Deceleration of heart rate
    c. Increase in gut motility
    d. Complete stopping of the heart
    e. None of the above; there would be no effect.

Answer 17

E

Question 18

30. A surprise phone call at 3 AM would likely cause all the following physiological reactions except
    a. inhibited salivation.
    b. pupil constriction.
    c. inhibited digestion.
    d. increased glucose production.
    e. sweating.

Answer 18

B

Question 19

34. The preganglionic neuron of the sympathetic system releases the neurotransmitter
    a. acetylcholine.
    b. epinephrine/norepinephrine.
    c. glutamate.
    d. GABA.
    e. calcium.

Answer 19

A

Question 20

35. Which of the following statements regarding the enteric system is false?
    a. Neurons are located entirely within the walls of the gut.
    b. It plays a role in segmentation.
    c. It is largely under autonomic control.
    d. In humans, it contains 200‒600 million neurons.
    e. It plays a role in peristalsis.

Answer 20

C

Question 21

36. Rhythms that continue in the absence of environmental information about time are called
    a. entrained rhythms.
    b. endogenous rhythms.
    c. circadian rhythms.
    d. free-running circadian rhythms.
    e. phasing factors.

Answer 21

B

Question 22

37. The _______ gene is not involved in the timekeeping mechanism in the mammalian suprachiasmatic nuclei.
    a. circ
    b. clock
    c. bmal1
    d. per
    e. cry

Answer 22

A

Question 23

41. Which of the following statements regarding biological clocks is false?
    a. The period of an animal’s free-running rhythm is affected by light‒dark cycles.
    b. Biological clocks are very sensitive to internal (cellular) temperature.
    c. Nocturnal animals often have periods of free-running rhythms longer than 24 hours.
    d. Biological clocks permit the timing of processes during 24-hour periods when environmental cues are unreliable.
    e. Circadian clocks enable animals to measure changes in photoperiod.

Answer 23

B

Question 24

44. Which of the following is the best description of the mechanism for circadian rhythm?
    a. There is an alternation between enhanced and inhibited expression of clock genes.
    b. Clock genes enhance gene expression of positive elements.
    c. Clock genes inhibit gene expression of positive elements.
    d. Clock genes inhibit expression of negative elements.
    e. The time-keeping mechanism depends only on the breakdown of negative elements.

Answer 24

A

Question 25

45. When the suprachiasmatic nucleus in a small mammal is destroyed,
    a. circadian rhythm becomes free-running.
    b. a zeitgeber is induced.
    c. the animal loses its ability to navigate.
    d. most circadian activity ceases.
    e. None of the above; there are no changes.

Answer 25

D

Question 26

49. Physiological timing mechanisms that, like stopwatches, permit the timing of parts of days for different functions are called
    a. stochastic rhythms.
    b. neurophysiological timers.
    c. circannual rhythms.
    d. subcircadian rhythms.
    e. interval timers.

Answer 26

E

Question 27

50. In vertebrates, melatonin is secreted in a circadian rhythm from
    a. the pineal gland.
    b. the suprachiasmatic nucleus.
    c. the circadian oscillator.
    d. the clock genes.
    e. complexes of PER protein and CRY protein

Answer 27

A

Question 28

1. Of a squid, an earthworm, a human, a cockroach, and a bacterium, how many have a brain?
   a. 1
   b. 2
   c. 3
   d. 4
   e. 5

Answer 28

D

Question 29

2. Which of the following terms refers to the concentration of nervous structures and functions in the head region?
   a. Centriolization
   b. Centralization
   c. Radialization
   d. Vulcanization
   e. Cephalization

Answer 29

E

Question 30

3. A _______ is a swelling that contains discrete aggregations of nerve cell bodies and processes.
   a. ganglion
   b. connective
   c. tract
   d. commissure
   e. neuropil

Answer 30

A

Question 31

4. Which of the following is characteristic of an arthropod central nervous system?
   a. A cross section of a ganglion consisting of gray matter and white matter.
   b. Neuronal bodies located throughout the entire animal.
   c. Lack of cephalization.
   d. A CNS consisting of a single continuous column.
   e. A CNS consisting of a chain of segmental ganglia.

Answer 31

E

Question 32

5. Most tissues in the body are under _______ control.
   a. neural
   b. endocrine
   c. both neural and endocrine
   d. neurohormonal
   e. neither neural nor endocrine

Answer 32

C

Question 33

6. Which of the following statements regarding the vertebrate nervous system is true?
   a. White matter is composed almost entirely of unmyelinated tracts of neurons.
   b. The cerebral cortex is part of the midbrain, or mesencephalon.
   c. Spinal nerves run from the brain to the spinal cord.
   d. Cranial nerves run within the brain and spinal cord.
   e. Gray matter is composed of intermingled neuronal cell bodies, processes, and synaptic contacts.

Answer 33

E

Question 34

7. Which of the following brain subdivisions is responsible for higher sensory, motor, and integrative functions?
   a. Diencephalon
   b. Mesencephalon
   c. Metencephalon
   d. Telencephalon
   e. Hindbrain

Answer 34

D

Question 35

8. A _______ is a term used when parts of the body are mapped onto the cerebral cortex in a way that preserves their anatomical position on the body.
   a. localization of function map
   b. somatotopic map
   c. somatosensory cortex
   d. brain map
   e. functional MRI

Answer 35

B

Question 36

9. Which of the following is not directly related to neuronal plasticity?
   a. Short-term memory
   b. Localized increases in brain metabolic activity
   c. Long-term memory
   d. Neural connections changing in strength
   e. New neurons developing

Answer 36

B

Question 37

10. Acid-secreting cells of the stomach are controlled by
    a. the autonomic system.
    b. the somatic system.
    c. the enteric division.
    d. hormones only.
    e. paracrine signaling only.

Answer 37

A

Question 38

11. The _______ division has a long preganglionic neuron synapsed with a short postganglionic neuron.
    a. sympathetic
    b. enteric
    c. parasympathetic
    d. somatic
    e. autonomic

Answer 38

C

Question 39

12. What are the divisions of the autonomic nervous system?
    a. Parasympathetic, sympathetic
    b. Somatic, enteric, peristaltic
    c. Sympathetic, parasympathetic, somatic
    d. Sympathetic, parasympathetic, enteric
    e. Somatic, enteric

Answer 39

D

Question 40

13. Application of acetylcholine all along the paravertebral ganglia will
    a. cause the heart to speed up.
    b. cause the heart to slow down.
    c. have no effect on the heart.
    d. cause the heart to speed up, then slow down.
    e. cause the heart to stop.

Answer 40

A

Question 41

14. Which of the following actions is not considered a sympathetic effect?
    a. Simulation of the secretion of epinephrine
    b. Inhibition of digestion
    c. Increased heart rate
    d. Increased blood pressure
    e. Constriction of lung passages

Answer 41

E

Question 42

15. Application of acetylcholine directly to the heart will
    a. cause the heart to speed up.
    b. cause the heart to slow down.
    c. have no effect on the heart.
    d. cause the heart to speed up, then slow down.
    e. cause the heart to stop.

Answer 42

B

Question 43

16. Which of the following is the most accurate definition of circadian rhythm?
    a. An endogenous rhythm that has a period of about one day
    b. An entrained rhythm that has a period of about one day
    c. An environmental rhythm that has a period of precisely 24 hours
    d. An endogenous rhythm that has a period of precisely 24 hours
    e. An entrained rhythm that has a period of precisely 24 hours

Answer 43

A

Question 44

17. A biological rhythm brought into phase with an environmental rhythm is said to be
    a. endogenous.
    b. a free-running circadian rhythm.
    c. entrained.
    d. a zeitgeber.
    e. phasing.

Answer 44

C

Question 45

18. In the absence of environmental cues, the biological rhythm that persists is called a(n)
    a. phasing factor.
    b. zeitgeber.
    c. entrained rhythm.
    d. free-running rhythm.
    e. circadian rhythm.

Answer 45

D

Question 46

19. The timekeeping mechanism in a cell typically depends on
    a. environmental information transduced into electrical information the cell can interpret.
    b. environmental information transduced into chemical information the cell can interpret.
    c. the rhythmic alternation between enhanced and inhibited expression of clock genes.
    d. the rhythmic alternation between expression of clock genes and transcription factors.
    e. the alternation of various sets of activating and inhibiting elements.

Answer 46

C

Question 47

20. Which of the following is not considered to be related to biological clocks?
    a. Melatonin
    b. Peristalsis
    c. Superchiasmatic nucleus
    d. Pineal gland
    e. Jet lag

Answer 47

B

Question 48

1. Describe the two major trends in nervous system evolution once animal lineages became bilaterally symmetrical.

Answer 48

The two major trends that characterize the evolution of nervous systems in bilaterally symmetrical phyla are centralization and cephalization. Centralization of nervous systems refers to a structural organization in which neurons are collected into central integrating areas rather than being randomly dispersed. Cephalization is the concentration of nervous structures and functions at one end of the body, in the head.

Question 49

2. Compare and contrast the organization of arthropod and vertebrate central nervous systems.

Answer 49

: Both the arthropod and vertebrate central nervous systems are centralized in organization and do show cephalization. However, the arthropod CNS consists of a chain of segmental ganglia, whereas the vertebrate CNS consists of a continuous column of neural tissue.

Question 50

3. Explain a somatotopic map.

Answer 50

A somatotopic map is a representation of the body that is projected to a brain area in a way that preserves the relative anatomical position of the parts the body. The relative sizes of brain areas that represent different parts of the body reflect the relative number of neurons serving that area.

Question 51

4. Briefly explain what is meant by synaptic plasticity. Provide one example.

Answer 51

: Synaptic plasticity refers to changes in synaptic properties over time. Synapses may change in strength and efficacy with development, maturation, and experiences such as learning. These changes can be temporary or permanent. For example, receptors can be modified in number within the synapse, synapses can be created or destroyed, or they can change size or efficacy. These changes can be seen microscopically or measured as changes in efficacy (e.g., changes in PSP amplitude).

Question 52

5. How do star-nosed moles exemplify the principles of brain functional organization?

Answer 52

: The star-nosed mole provides a great example of functional organization of the brain because the size of representations in the brain reflects the importance of different sensory qualities. Somatosensory representations of the star and of the forepaws are large, whereas areas devoted to vision are small. The star has three somatosensory representations that together occupy more area in the brain than that devoted to the rest of the body.

Question 53

6. Compare and contrast the functions of the sympathetic and parasympathetic nervous systems.

Answer 53

: Sympathetic and parasympathetic systems are both divisions of the autonomic nervous system that functionally link the CNS with autonomic effectors. However, the two divisions typically have opposing effects. The sympathetic actions mediate “fight-or-flight” responses, whereas the parasympathetic actions mediate “rest-and-digest.”

Question 54

7. If atropine is an antagonist to acetylcholine, explain what this drug would do to the heart.

Answer 54

If atropine is added to the heart, it will competitively bind to ACh receptors on the heart. Since ACh receptors on the heart mediate the actions of the parasympathetic system, blocking this signal on the heart will effectively increase its rate.

Question 55

8. Describe what is meant by entrainment and provide an example.

Answer 55

: Entrainment is the process by which a biological rhythm is brought into phase with an environmental rhythm. For example, the onset of darkness each night entrains the circadian rhythm of the activity of nocturnal flying squirrels.

Question 56

9. Compare and contrast free-running circadian rhythms of nocturnal and diurnal mammals.

Answer 56

Free-running circadian rhythms of nocturnal and diurnal mammals are both not exactly 24 hours and thus will tend to slowly shift the sleep‒wake cycles of these animals. Nocturnal mammals tend to have periods of free-running rhythm that are longer than 24 hours and many diurnal mammals tend to have periods shorter than 24 hours.

Question 57

10. Explain how the pineal gland may operate differently in nonmammalian vertebrates compared to mammals.

Answer 57

: The pineal physiology of nonmammalian vertebrates differs from that of mammals in two ways. First, the nonmammalian pineal gland may be endogenously rhythmic and can act as a primary circadian control center. Second, the pineal gland is often light-sensitive and acts as a “third eye,” providing extraocular information about the environmental day‒night cycle.