Chapter 5 Flashcards Preview

Brain and Behavior > Chapter 5 > Flashcards

Flashcards in Chapter 5 Deck (174):
1

T/F The human central nervous system begins to form when the embryo is about 10 weeks old.

False

2

T/F Once the brain is fully developed, the anatomy of the brain is unchanging.

False

3

T/F The fluid-filled cavity within the neural tube becomes the central canal of the spinal cord and the four ventricles of the brain.

True

4

T/F Proliferation is the production of new cells.

True

5

T/F Axons are usually formed before the dendrites.

True

6

T/F After cells have differentiated as neurons or glia, they migrate.

True

7

T/F An early and fast stage of neuronal development is myelination.

False

8

T/F Some neurons provide the myelination for other neurons.

False

9

T/F Myelination of the brain and spinal cord is complete by the time of birth.

False

10

T/F Synaptogenesis is a process that begins before birth and continues throughout life.

True

11

T/F Recent evidence suggests that adult vertebrate brains generate new neurons.

True

12

T/F The number of neurons in the brain is continually increasing throughout life.

False

13

T/F Mammals and amphibians are similar in that they can both easily generate new axons.

False

14

T/F The brain requires millions of chemicals to correctly guide the growth of axons to their target locations.

False

15

T/F Apoptosis is distinct from necrosis, which is death caused by an injury or a toxic substance.

True

16

T/F Nerve growth factor is a chemical that promotes the survival and activity of neurons.

True

17

T/F The developing infant brain is highly resistant to damage.

False

18

T/F Physical exercise is important for increased dendrite growth and branching.

True

19

T/F Exercise may account for some of the neural benefits that come from rearing rats in an enriched environment.

True

20

T/F A rat in a more stimulating environment develops a thicker cortex, more dendritic branching, and improved learning.

True

21

T/F The most common cause of brain damage in children is closed head injury.

True

22

T/F In strokes caused by ischemia or hemorrhage, neurons die from overstimulation.

True

23

T/F The damaging effects of a stroke can be limited if treated within a short period of time.

True

24

T/F Diaschisis refers to the decreased activity of surviving neurons after damage to other neurons.

True

25

T/F One effective method to overcome diaschisis after brain damage is to administer stimulant drugs.

True

26

T/F An axon in the peripheral nervous system is more likely to recover after being cut than if it is crushed.

False

27

T/F Paralysis caused by spinal cord injury is usually only temporary in humans.

False

28

T/F Denervation supersensitivity results from the disuse of incoming axons.

False

29

T/F Recent evidence suggests that phantom limb pain is caused by sensations coming from the stump of the amputated limb.

False

30

T/F Deafferentation of the left arm results in the inability to move it.

False

31

The ability of the brain to change its anatomy over time, within limits, is known as:
a. plasticity.
b. regression.
c. connectivity.
d. long term potentiation.

a. plasticity.

32

Early in development, the nervous system begins as a:
a. tube surrounding a fluid-filled cavity.
b. spherical structure in the center of the embryo.
c. diffuse system of cells scattered throughout the body.
d. single layer of cells covering the heart and other internal organs.

a. tube surrounding a fluid-filled cavity.

33

The human central nervous system:
a. begins to form during the fetal stage.
b. is unlike all other vertebrate central nervous systems in its developmental process.
c. begins to form when the embryo is about two weeks old.
d. begins to form when the embryo is about two months old.

c. begins to form when the embryo is about two weeks old.

34

As the neural tube sinks under the surface of the skin, the forward end enlarges and differentiates into the:
a. spine, midbrain, and forebrain.
b. hindbrain, midbrain, and forebrain.
c. hindbrain, midbrain.
d. midbrain, forebrain.

b. hindbrain, midbrain, and forebrain.

35

When do the ventricles and the central canal of the spinal cord form?
a. shortly after birth in humans
b. just as the forebrain starts its rapid phase of growth
c. early in embryonic development
d. during the third trimester

c. early in embryonic development

36

The fluid-filled cavity of the developing neural tube becomes the:
a. forebrain.
b. midbrain.
c. spinal cord.
d. ventricular system.

d. ventricular system.

37

What is the production of new neurons called?
a. differentiation
b. migration
c. myelination
d. proliferation

d. proliferation

38

Stem cells are important for which of the following developmental processes?
a. migration
b. proliferation
c. myelination
d. synaptogenesis

b. proliferation

39

Proliferation is the:
a. production of new cells.
b. movement of primitive neurons and glia.
c. formation of dendrites and an axon.
d. insulation process that occurs on some axons.

a. production of new cells.

40

Proliferation occurs:
a. at the top of the spinal column.
b. around the vesicles.
c. around the ventricles.
d. at the expanding edge of the brain.

c. around the ventricles.

41

After cells have differentiated as neurons or glia, they:
a. differentiate.
b. proliferate.
c. myelinate.
d. migrate.

d. migrate.

42

Chemicals known as ____ and ____ guide neuron migration.
a. immunoglobulins; sodium
b. glia; neurothrophins
c. immunoglobulins; chemokines
d. chemokines; neurothrophins

c. immunoglobulins; chemokines

43

What term describes the movement of primitive neurons and glia within the developing nervous system?
a. Differentiation
b. Migration
c. Myelination
d. Proliferation

b. Migration

44

Which of the following would most likely interfere with migration of neurons during development?
a. altering the chemical paths
b. damaging dendrites
c. loss of myelin
d. increased differentiation

a. altering the chemical paths

45

Migration is the:
a. production of new cells.
b. movement of primitive neurons and glia.
c. gradual formation of dendrites and an axon.
d. insulation process that occurs on some axons.

b. movement of primitive neurons and glia.

46

Immunoglobulins and chemokines play an important role in neural:
a. migration.
b. proliferation.
c. synaptogenesis.
d. apoptosis.

a. migration.

47

Which of the following best characterizes how axons arrive at the correct target cells?
a. They follow electrical gradients.
b. They follow chemical gradients from the target cell.
c. Axons send out chemicals to the target cells.
d. Target cells send out branches for the axons to follow.

b. They follow chemical gradients from the target cell.

48

Migration requires:
a. a precise chemical environment.
b. cells which are myelinated.
c. mature neurons.
d. neurons with fully developed dendrites.

a. a precise chemical environment.

49

Differentiation is the:
a. production of new cells.
b. movement of primitive neurons and glia.
c. formation of dendrites and an axon.
d. insulation process that occurs on some axons.

c. formation of dendrites and an axon.

50

What is the process called when a primitive neuron begins to develop dendrites and an axon?
a. Differentiation
b. Migration
c. Myelination
d. Proliferation

a. Differentiation

51

The formation of a neuron’s distinctive shape occurs during the ____ stage of neurogenesis.
a. proliferation
b. migration
c. differentiation
d. myelination

c. differentiation

52

Whether or not a transplanted immature neuron adopts the properties of neurons in the new location or retains at least some properties of neurons from where it was taken from depends largely on how much the transplanted neuron has:
a. myelinated.
b. proliferated.
c. migrated.
d. differentiated.

d. differentiated.

53

After the migrating neuron reaches its destination, ____ begin to form.
a. dendrites
b. axons
c. nuclei
d. ganglions

a. dendrites

54

Myelination is a process common to:
a. all vertebrate axons.
b. all vertebrate dendrites.
c. some vertebrate axons.
d. some invertebrate axons.

c. some vertebrate axons.

55

For some axons, glial cells produce an insulating sheath that makes rapid transmission possible. What is this process called?
a. Differentiation
b. Migration
c. Myelination
d. Proliferation

c. Myelination

56

In humans, myelination first occurs in the:
a. spinal cord.
b. hindbrain.
c. midbrain.
d. forebrain.

a. spinal cord.

57

Myelination in the human brain:
a. is complete upon birth.
b. is complete around the second birthday.
c. is complete sometime shortly after adolescence.
d. continues well into the adult years.

d. continues well into the adult years.

58

The stages of neurogenesis that occur for the longest duration are:
a. myelination and synaptogenesis.
b. proliferation and myelination.
c. migration and proliferation.
d. differentiation and migration.

a. myelination and synaptogenesis.

59

The final stage of neurodevelopment is called:
a. synaptogenesis.
b. differentiation.
c. migration.
d. fusion.

a. synaptogenesis.

60

The formation of new synapses is called:
a. synaptogenesis.
b. differentiation.
c. migration.
d. fusion.

a. synaptogenesis.

61

New neurons are known to develop in all of the following cases EXCEPT:
a. olfactory receptors.
b. the human corpus callosum.
c. the brain area responsible for birdsong.
d. hippocampus of mammals.

b. the human corpus callosum.

62

As a rule, all vertebrate neurons develop during an embryological stage. Among the few types of neurons that can develop in adulthood are:
a. ganglion cells in the retina.
b. olfactory receptors.
c. motor nerves in the spinal cord.
d. long-axoned neurons of the primary motor cortex.

b. olfactory receptors.

63

Brain cells that are neither neurons nor glia, but which are capable of dividing and then differentiating into neurons or glia, are called:
a. parallel fibers.
b. intrinsic cells.
c. stem cells.
d. glomeruli.

c. stem cells.

64

What happened when Weiss grafted an extra leg onto a salamander adjacent to one of the hindlegs?
a. The new leg gradually took over for the old.
b. The new leg withered and died.
c. Nerves from the old leg attached to the new in a random fashion.
d. Branches of axons from the old leg attached to corresponding muscles in the new.

d. Branches of axons from the old leg attached to corresponding muscles in the new.

65

What process occurs when axons attempt to form connections to a grafted limb in a salamander?
a. Axons connect randomly, but only muscles "tuned" to the right message respond.
b. Axons connect randomly and muscles learn to coordinate through experience.
c. Axons find their way to corresponding muscles in the new leg.
d. A lack of nerve growth fiber leads to the degeneration of the new leg.

c. Axons find their way to corresponding muscles in the new leg.

66

If you cut the optic nerve of a newt, what happens?
a. The fibers grow back and attach to random targets, so they see a scrambled picture.
b. The fibers grow back and attach to their original targets, resulting in normal vision.
c. The newt remains blind, since neurons do not regenerate.
d. The fibers attach to multiple targets, resulting in blurry vision.

b. The fibers grow back and attach to their original targets, resulting in normal vision.

67

Chemicals in the amphibian tectum guide the growth of axons from the retina to their correct location in the tectum by:
a. having dozens of different growth factors.
b. using an electrical gradient.
c. using a chemical gradient.
d. glial cell transportation.

c. using a chemical gradient.

68

Roger Sperry cut a newt's optic nerve and rotated the eye. Axons from what used to be the dorsal part of the retina (now located on the ventral side) grew back to the target areas:
a. that ordinarily get input from the dorsal retina.
b. that ordinarily get input from the ventral retina.
c. that ordinarily get input from the center of the retina.
d. equally and diffusely.

a. that ordinarily get input from the dorsal retina.

69

When Sperry cut a newt's optic nerve and rotated the eye by 180 degrees, each axon:
a. degenerated.
b. regenerated to a random location.
c. regenerated to the area where it had originally been.
d. regenerated, but to the area appropriate to its new location.

c. regenerated to the area where it had originally been.

70

What visual capabilities did Sperry's newt have after Sperry cut the optic nerve and rotated the eye?
a. It regained normal vision.
b. It saw the world upside down and backwards.
c. It required experience to relearn how to see.
d. It remained blind.

b. It saw the world upside down and backwards.

71

Which of the following best describes the process by which developing axons find their general target areas?
a. completely random growth
b. shape attraction
c. electrical attraction
d. chemical attraction

d. chemical attraction

72

Axons sort themselves over the surface of the target area:
a. by following a gradient of chemicals.
b. through apoptosis.
c. through necrosis.
d. based on their size.

a. by following a gradient of chemicals.

73

Which of the following are selective as axons form synapses with target cells?
a. axons, but not target cells
b. target cells, but not axons
c. both axons and target cells
d. neither axons nor target cells

c. both axons and target cells

74

Competition of neurons for postsynaptic sites results in survival of only the most successful axons. This general principle is called:
a. natural selection.
b. evolution.
c. apoptosis.
d. neural Darwinism.

d. neural Darwinism.

75

The concept that neurons refine their many connections based on which ones are most successful is known as:
a. natural selection.
b. evolution.
c. survival of the fittest.
d. neural Darwinism.

d. neural Darwinism.

76

What is meant by neural Darwinism?
a. The brains of higher primates are the ones that are most similar to those of humans.
b. Most individual differences in the brain are due to genetic mutations.
c. Successful neurons develop while less successful neurons weaken or die.
d. Successful neurons reproduce while less successful neurons do not.

c. Successful neurons develop while less successful neurons weaken or die.

77

____ steer new axonal branches and synapses in the right direction.
a. Chemokines
b. Immunoglobulin
c. Glia
d. Neurotrophins

d. Neurotrophins

78

Why is it that all neurons in a healthy adult brain have made appropriate connections?
a. Chemical messages from our muscles tell our brain how many neurons to form and that number perfectly matches the connections required.
b. If an axon does not make the appropriate connections by a certain age, it dies.
c. We are born with all connections formed.
d. Connections form rapidly, but we learn to use whatever connections have formed.

b. If an axon does not make the appropriate connections by a certain age, it dies.

79

Why is it that every axon in an adult mammal has a target cell (muscle cell or other neuron) with which it makes synaptic contact?
a. Each target cell causes the growth of a neuron and its axon.
b. After formation, axons release a chemical that causes a target cell to form.
c. Axons that fail to find a target cell die.
d. An axon will make contact with any kind of cell and adjust its function as necessary.

c. Axons that fail to find a target cell die.

80

What is signaled by nerve growth factor (NGF)?
a. That a target cell has "accepted" an axon
b. Which target cell a growing axon should connect with
c. That axons should elongate as the body grows bigger
d. The need for new neurons to form in brain areas that are lacking in neurons

a. That a target cell has "accepted" an axon

81

Nerve growth factor (NGF):
a. promotes the survival and growth of the axon.
b. is a fuel metabolized by neurons.
c. promotes programmed cell death.
d. is a hormone first released at puberty.

a. promotes the survival and growth of the axon.

82

Necrosis:
a. is a programmed mechanism of cell death.
b. is cell death caused by an injury or a toxic substance.
c. promotes the survival and growth of dendrites.
d. promotes the activity of neurons.

b. is cell death caused by an injury or a toxic substance.

83

Apoptosis:
a. is a programmed mechanism of cell death.
b. promotes the survival and growth of the axon.
c. promotes the survival and growth of dendrites.
d. promotes the activity of neurons.

a. is a programmed mechanism of cell death.

84

If a sympathetic nervous system axon does not receive enough nerve growth factor, the neuron will:
a. kill itself.
b. grow a shorter axon.
c. compensate by growing more dendrites.
d. decrease its velocity of action potentials.

a. kill itself.

85

What is apoptosis?
a. the growth of an axon in response to NGF
b. the leakage of transmitters from vesicles
c. a program of "suicide" by a neuron
d. dendritic branching in the sympathetic nervous system

c. a program of "suicide" by a neuron

86

Some neurons die during development because:
a. they are surrounded by glia.
b. they do not receive enough GABA.
c. they receive too much NGF.
d. they fail to receive enough NGF.

c. they receive too much NGF.

87

The function of neurotrophins is to:
a. inhibit proliferation.
b. promote survival of axons.
c. be used as fuel.
d. signal that an axon has been "rejected."

b. promote survival of axons.

88

Which of the following is NOT a function of neurotrophins?
a. Direct axonal growth during development.
b. Increase axonal branching in mature neurons.
c. Increase regrowth of axons after brain damage.
d. Induce apoptosis of neurons.

d. Induce apoptosis of neurons.

89

Developing neurons need ____ for survival.
a. neurotrophins only
b. neurotrophins and synaptic input
c. synaptic input only
d. apoptosis

b. neurotrophins and synaptic input

90

An axon that does not receive enough neurotrophins from a target cell will:
a. branch out and form other synapses on other cells.
b. manufacture its own neurotrophins.
c. degenerate and die.
d. fail to reabsorb transmitters that have already been released.

c. degenerate and die.

91

In development, neurotrophins ____. During adulthood, they ___.
a. preserve neurons; produce apoptosis
b. produce apoptosis; increase neuronal branching
c. facilitate differentiation; facilitate migration
d. preserve neurons; increase neuronal branching

d. preserve neurons; increase neuronal branching

92

At later stages of the neuron's development, neurotrophins:
a. increase the branching of axons.
b. cause the neuron's death.
c. become converted into myelin.
d. connect the axon to axons of adjoining cells.

a. increase the branching of axons.

93

Which statement most accurately describes embryonic development of the nervous system in humans?
a. The majority of cells remain as primitive neurons until birth.
b. All synapses that are formed are permanent.
c. Neurons form before birth; synapses form after birth.
d. Far more neurons are produced than will ultimately survive.

d. Far more neurons are produced than will ultimately survive.

94

In response to nervous system injury, neurotrophins:
a. cause the neuron's death.
b. reduce inflammation due to this injury.
c. increase regrowth of damaged axons.
d. promote apoptosis.

c. increase regrowth of damaged axons

95

Massive cell death in the brain during prenatal development is:
a. an indication of a genetic abnormality.
b. an indication of restricted blood flow to the fetus.
c. usually due to an autoimmune disorder.
d. normal.

d. normal.

96

The most likely explanation for the excess proliferation of neurons in early development is that it:
a. compensates for connection errors.
b. uses up excess stored fuel.
c. increases learning capacity when it is most needed.
d. prevents apoptosis.

a. compensates for connection errors.

97

For survival, developing neurons need:
a. neurotrophins only.
b. neurotrophins and synaptic input.
c. synaptic input only.
d. apoptosis.

b. neurotrophins and synaptic input.

98

Compared to an adult, a fetus has:
a. more neurons.
b. approximately the same number of neurons.
c. about half the number of neurons.
d. about one-tenth the number of neurons.

a. more neurons.

99

After maturity, the apoptotic mechanisms become:
a. hyperactive.
b. extinct.
c. dormant.
d. very complex.

c. dormant.

100

An iodine deficiency in the diet can lead to an inadequate production of thyroid hormones. What is the result if this occurs in an infant or developing fetus?
a. Down's syndrome
b. mental retardation
c. Tourette's syndrome
d. accelerated body growth

b. mental retardation

101

What modern day practice helps prevent an inadequate production of thyroid hormones?
a. fluoride in drinking water
b. processed sugar
c. iodized salt
d. artificial sweeteners

c. iodized salt

102

In infants, anesthetic drugs can increase:
a. proliferation.
b. migration.
c. myelination.
d. apoptosis.

d. apoptosis.

103

Children of mothers who drink heavily during pregnancy are born with:
a. fetal alcohol syndrome
b. Turner's syndrome
c. Klinefelter's syndrome
d. PKU

a. fetal alcohol syndrome

104

The mechanism of fetal alcohol syndrome probably relates to:
a. overexcited neurons.
b. apoptosis.
c. decreases apoptosis.
d. necrosis.

b. apoptosis.

105

What condition would be suspected if a young child shows decreased alertness, hyperactivity, mental retardation, motor problems, a heart defect, and abnormal facial features?
a. fetal alcohol syndrome
b. Turner's syndrome
c. Klinefelter's syndrome
d. PKU

a. fetal alcohol syndrome

106

The most likely reason that children with fetal alcohol syndrome have brain abnormalities is because alcohol:
a. overexcites neurons.
b. stimulates nerve growth factor.
c. decreases apoptosis.
d. decreases release of neurotrophins.

d. decreases release of neurotrophins.

107

What brain abnormalities are found in children with fetal alcohol syndrome?
a. short axons with few branches
b. short dendrites with few branches
c. lack of dopamine receptors
d. smaller than normal ventricles

b. short dendrites with few branches

108

Alcohol suppresses the release of ____, the brain’s main excitatory transmitter.
a. 5-HT
b. DA
c. GABA
d. glutamate

d. glutamate

109

How much alcohol, if any, can a pregnant woman drink without worrying about the negative effects on her child?
a. The equivalent of two cocktails a day
b. The equivalent of one beer a day
c. Anything less than what causes her to act drunk
d. Unknown, and therefore abstention is recommended

d. Unknown, and therefore abstention is recommended

110

Alcohol can damage the developing brain by:
a. tearing the cell membrane.
b. increasing synaptic inhibition and therefore apoptosis.
c. overstimulating neurons.
d. interfering with protein production.

b. increasing synaptic inhibition and therefore apoptosis.

111

Children of mothers who use cocaine during pregnancy:
a. have a slightly higher birth weight.
b. are likely to develop Turner's syndrome.
c. have a slightly lower IQ score.
d. are born with severe abnormalities resembling cerebral palsy.

c. have a slightly lower IQ score.

112

Children of mothers who smoke cigarettes during pregnancy are at an increased risk of:
a. intellectual deficits.
b. Korsakoff's syndrome.
c. Rett syndrome.
d. Parkinson's disease.

a. intellectual deficits.

113

On average, exposure to nicotine during pregnancy increases risk of ____ deficits.
a. emotional
b. attention
c. learning
d. memory

b. attention

114

Which of the following, if any, would be more damaging to an adult brain than to the brain of an infant or fetus?
a. Exposure to alcohol
b. Infections like German measles
c. Iodine deficiency in the diet
d. All of these are more damaging to an infant brain.

d. All of these are more damaging to an infant brain.

115

Keeping animals in a varied environment with stimulation increases the:
a. branching of dendrites.
b. speed of action potentials.
c. density of Nodes of Ranvier along the axon.
d. thickness of axons.

a. branching of dendrites.

116

The areas of the cortex used by expert video game players are most likely to ____ than the same cortical areas of those who don’t play video games.
a. be thicker
b. have smaller, but a greater number of neurons
c. have faster action potentials
d. be more resistant to transcortical stimulation

a. be thicker

117

Which of the following aspects of brain and neural functioning can be most clearly altered by experience?
a. velocity of action potentials
b. structure of dendrites and axons
c. chemical constituents of the ventricles
d. number of laminae in the cerebral cortex

b. structure of dendrites and axons

118

What is different about rats raised in an enriched environment in comparison to rats raised in an impoverished environment?
a. a more pleasant personality
b. improved learning performance
c. better parenting skills
d. nothing

b. improved learning performance

119

Research in people over age 60 who were randomly assigned to experience six months of aerobic exercise showed:
a. that they developed more axons.
b. that they developed less tumors.
c. that they developed greater thickness of the cortex.
d. that they developed less thickness of the cortex.

c. that they developed greater thickness of the cortex.

120

Which of the following factors seems to be particularly important for branching of neurons during brain development?
a. Physical activity
b. Playing logic games
c. Having good teachers
d. Having a sterile environment

a. Physical activity

121

Brain studies of blind people suggest that they have greater attention to touch and auditory stimulation because:
a. cortical areas for touch and audition are thicker.
b. their visual cortex is used for touch and verbal tasks.
c. they have greater neural branching.
d. they have greater neurotrophin release.

b. their visual cortex is used for touch and verbal tasks.

122

An MEG study of professional musicians listening to pure tones showed that:
a. professional musicians had brain responses that were twice as strong as non-musicians.
b. professional musicians had slightly less brain responses as non-musicians.
c. professional musicians had drastically less brain responses as non-musicians.
d. professional musicians had brain responses five times as strong as non-musicians.

a. professional musicians had brain responses that were twice as strong as non-musicians.

123

Musicians who use the left hand to finger the violin strings have some alterations in one brain area, which is the:
a. left hemisphere prefrontal cortex.
b. right hemisphere prefrontal cortex.
c. left hemisphere postcentral gyrus.
d. right hemisphere postcentral gyrus.

d. right hemisphere postcentral gyrus.

124

Focal hand dystonia, sometimes called "musician's cramp", is caused by:
a. extreme overlap of cortical representation of the fingers.
b. deterioration of muscles in the hand.
c. demyelination of neurons in the fingers.
d. buildup of excess GABA in the temporal cortex.

a. extreme overlap of cortical representation of the fingers.

125

Closed head injury is:
a. the most common cause of brain damage in young adults.
b. usually fatal.
c. the most common cause of Korsakoff's syndrome.
d. related to Alzheimer's disease.

a. the most common cause of brain damage in young adults.

126

The most common cause of brain damage in young people is:
a. infection.
b. gunshot wounds.
c. stroke.
d. closed head injury.

d. closed head injury.

127

Closed head injury results in damage partially because of:
a. increased production of myelin.
b. excessive deficit of neurotrophins.
c. rotational forces that push the brain against the inside of the skull.
d. infection.

c. rotational forces that push the brain against the inside of the skull.

128

A sharp blow to the head resulting from an assault or trauma that does not actually puncture the brain is called a:
a. stroke.
b. cerebrovascular accident.
c. hemorrhage.
d. closed head injury.

d. closed head injury.

129

Which of the following is the most common cause of a stroke?
a. Lack of glucose
b. Ischemia from an obstruction of an artery
c. Hemorrhage of an artery
d. Blow to the head

b. Ischemia from an obstruction of an artery

130

A stroke caused by an artery rupturing is also known as:
a. ischemia.
b. hemorrhage.
c. closed head injury.
d. penumbra.

b. hemorrhage.

131

Which of the following is not a cerebrovascular accident?
a. Ischemia
b. Hemorrhage
c. Stroke
d. Penumbra

d. Penumbra

132

A stroke which is caused when an artery ruptures is also known as:
a. ischemia.
b. hemorrhage.
c. closed head injury.
d. penumbra.

b. hemorrhage.

133

Ischemia is to ____ as hemorrhage is to ____.
a. older individuals; younger individuals
b. proximal; distal
c. obstruction; rupture
d. barely noticeable; lethal

c. obstruction; rupture

134

What does edema mean?
a. Lack of glucose
b. Ischemia from an obstruction of an artery
c. Hemorrhage of an artery
d. Swelling due to accumulation of fluid

b. Ischemia from an obstruction of an artery

135

After a stroke, cells in the penumbra:
a. are the first to die.
b. help to remove dead or dying cells in the area of damage.
c. quickly become more active, compensating for the area of damage.
d. may die days or weeks after a stroke.

d. may die days or weeks after a stroke.

136

After ischemia, neurons deprived of blood:
a. transform from neurons into glia.
b. lose much of their oxygen and glucose supplies.
c. break down the blood-brain barrier.
d. increase the velocity of their action potentials.

b. lose much of their oxygen and glucose supplies.

137

____ cells proliferate after a stroke.
a. Penumbra
b. Microglia
c. Ischemia
d. Cancer

b. Microglia

138

Ischemia and hemorrhage kill neurons by:
a. understimulating them.
b. overstimulating them.
c. overactivating the sodium-potassium pump.
d. depleting the glutamate supply available to neurons.

b. overstimulating them.

139

A stroke kills neurons in two waves, first by ____ and second by ____.
a. overstimulation; understimulation
b. Understimulation; overstimulation
c. collateral sprouting; denervation supersensitivity
d. denervation supersensitivity; collateral sprouting

a. overstimulation; understimulation

140

Damage due to stroke caused by ischemia can be minimized by administering a drug that:
a. breaks up blood clots.
b. overstimulates neurons in and around the damaged area.
c. increases the release of glutamate.
d. slows down the sodium-potassium pump.

a. breaks up blood clots.

141

Although the following methods may or may not actually work, which one would theoretically be of potential benefit to stroke victims?
a. increasing activity at glutamate receptors
b. opening sodium channels
c. closing potassium channels
d. blocking glutamate receptors

d. blocking glutamate receptors

142

Tissue plasminogen activator (tPA):
a. is recommended for hemorrhage.
b. overstimulates glutamate receptors.
c. should be administered a few days after stroke.
d. is helpful in cases of ischemia.

d. is helpful in cases of ischemia.

143

Which of the following would be the best treatment for helping someone who is suffering from a stroke caused by a blood clot?
a. decrease activity of the sodium-potassium pump
b. warm the brain
c. administer tPA
d. enhance glutamate release

c. administer tPA

144

In research aimed at minimizing damage due to stroke, attempts to prevent overstimulation of cells have produced:
a. very promising results.
b. disappointing results.
c. a complex interaction between age of patient and season of the year.
d. positive results in humans, but not so for animals.

b. disappointing results.

145

Researchers have tried using drugs that block apoptosis. Results have been:
a. favorable in animals and human trials.
b. favorable in animal trials but too costly to try with humans.
c. favorable in animal trials but difficult or impractical to apply to humans.
d. unfavorable in all research trials.

c. favorable in animal trials but difficult or impractical to apply to humans.

146

One approach in minimizing stroke damage in laboratory animals is the use of:
a. calcium
b. serotonin
c. cannabinoids
d. opioids

c. cannabinoids

147

To date, the most effective laboratory method minimizing the damage resulting from stroke in nonhuman animals has been to:
a. use drugs which trap free radicals.
b. use drugs which effect cannabinoids.
c. use neurotrophins which block apoptosis.
d. cool the brain.

d. cool the brain.

148

In hemorrhage, cells in the penumbra:
a. lose much of their oxygen.
b. lose much of their glucose.
c. are flooded with excess oxygen.
d. act quickly to strengthen the blood-brain barrier.

c. are flooded with excess oxygen.

149

Research on laboratory animals indicates that cannabinoids are most effective if taken:
a. as soon as the stroke occurs.
b. within 20 minutes of the stroke.
c. steadily for one month.
d. shortly before the stroke.

d. shortly before the stroke.

150

Diaschisis refers to the:
a. increase in activity of neurons surrounding a damaged area.
b. decreased activity of surviving neurons after other neurons are damaged.
c. increased activity in the cerebral cortex after damage to any part of the brain.
d. increased activity in the hypothalamus after damage to any part of the brain.

b. decreased activity of surviving neurons after other neurons are damaged.

151

A lesion in the hypothalamus can lead to decreased activity in the cerebral cortex, even though the cerebral cortex is undamaged. The decreased activity in the cortex because of the loss of incoming neurons is called:
a. diaschisis.
b. deafferentation.
c. cytotoxicity.
d. hyperpolarization.

a. diaschisis.

152

To promote recovery, stroke victims should be given:
a. stimulant drugs immediately after the stroke.
b. any drug that decreases dopamine.
c. stimulant drugs a few days after the stroke.
d. tranquilizers a few days after the stroke.

c. stimulant drugs a few days after the stroke.

153

Following a stroke, amphetamine could help by:
a. inducing apoptosis.
b. blocking activity in overstimulated areas of the brain.
c. blocking glutamate release.
d. increasing activity in understimulated areas of the brain.

d. increasing activity in understimulated areas of the brain.

154

Which of the following treatments would be most likely to help a patient starting several days after a stroke?
a. Injecting a drug to block dopamine
b. Administering tranquilizers
c. Extensive bed rest
d. Giving stimulant drugs combined with physical therapy

d. Giving stimulant drugs combined with physical therapy

155

Which axons will regenerate to a significant degree if cut or crushed?
a. Those in invertebrates but not in vertebrates
b. Only those which are unmyelinated
c. Those in the central nervous system but not in the peripheral nervous system
d. Those in the peripheral nervous system but not in the central nervous system

d. Those in the peripheral nervous system but not in the central nervous system

156

What is one impediment to regeneration of axons in the mammalian central nervous system?
a. Inhibitory chemicals secreted by the damaged portion of the axon
b. Bacterial infections caused by the decaying tissue
c. Large amounts of scar tissue
d. Inhibitory messages sent from the cell nucleus when an axon is damaged

c. Large amounts of scar tissue

157

A damaged axon:
a. will never grow back.
b. can grow back under certain circumstances.
c. will grow back if its dendrites do also.
d. will grow back only if it is myelinated.

b. can grow back under certain circumstances.

158

After a cut through the spinal cord, axons grow back enough to restore functioning in certain ____ but not in ____.
a. adults; infants
b. infants; adults
c. fish; mammals
d. mammals; primates

c. fish; mammals

159

One limiting factor in the ability of damaged axons to regenerate in the brain and spinal cord is that:
a. they don't have any myelin to guide them.
b. they regenerate only one to two millimeters.
c. growing dendrites compete with growing axons.
d. there are no muscles in the brain and spinal cord to guide the growth.

b. they regenerate only one to two millimeters.

160

Scar tissue and myelin are similar in that they both:
a. secrete chemicals to restore axons.
b. are produced after brain damage.
c. are formed in normal development of the nervous system.
d. secrete chemicals that inhibit axon growth.

d. secrete chemicals that inhibit axon growth.

161

What is one impediment to regeneration of axons in the mammalian central nervous system?
a. Inhibitory chemicals secreted by the damaged portion of the axon
b. Bacterial infections caused by the decaying tissue
c. Glia release chemicals that inhibit axon growth
d. Inhibitory messages sent from the cell nucleus when an axon is damaged

c. Glia release chemicals that inhibit axon growth

162

One reason why axons regenerate better in the peripheral nervous system of mammals than in the central nervous system is that the peripheral nervous system:
a. has fewer myelinated axons.
b. has glial cells that destroy scar tissue.
c. maintains a temperature closer to that at which embryonic cells form.
d. produces a chemical that promotes axon growth.

d. produces a chemical that promotes axon growth.

163

Central nervous system axons regenerate much better in fish than in mammals because fish:
a. nerves do not have to travel so far to reach their target.
b. myelin does not secrete proteins that inhibit axon growth.
c. nerves have so much more myelin than do mammal nerves.
d. myelin secretes a protein that accelerates regeneration.

b. myelin does not secrete proteins that inhibit axon growth.

164

Central nervous system axons regenerate much better in fish than in mammals because:
a. fish nerves do not have to travel so far to reach their target.
b. fewer fish nerves are covered with myelin.
c. fish do not produce as much scar tissue.
d. fish generally have a lower body temperature.

c. fish do not produce as much scar tissue.

165

After central nervous system damage, myelin:
a. degenerates and dies.
b. secretes proteins that inhibit axon regrowth.
c. secretes proteins that enhance some regrowth of axons.
d. becomes thicker in surviving axons.

b. secretes proteins that inhibit axon regrowth.

166

If some of the axons innervating a given cell are destroyed or if they become inactive, what compensatory process takes place in the remaining presynaptic cells?
a. activation of previously silent synapses
b. removal of toxins
c. denervation supersensitivity
d. collateral sprouting

d. collateral sprouting

167

What is the term for the new branches that may form in uninjured axons after damage to surrounding axons?
a. collateral sprouts
b. bifurcations
c. denervation supersensitivity
d. diaschisis

a. collateral sprouts

168

After damaging input to the hippocampus, collateral sprouting is associated with improvements in:
a. memory.
b. taste.
c. vision.
d. hearing.

a. memory.

169

After damage to a set of axons, neurotrophins induce nearby:
a. injured axons to form new branches.
b. injured dendrites to form new branches.
c. uninjured axons to form new branches.
d. uninjured dendrites to form new branches.

c. uninjured axons to form new branches.

170

If a tree branch is cut, the surrounding branches may grow enough to fill in the empty space left by the missing branch. When this same type of event occurs in the nervous system following brain damage, it is called:
a. hemiplegia.
b. denervation supersensitivity.
c. collateral sprouting.
d. tree branching.

c. collateral sprouting.

171

After damage to the connections to the left hippocampus from the left entorhinal cortex, sprouts develop from the:
a. left occipital cortex.
b. right entorhinal cortex.
c. left hippocampus.
d. right hippocampus.

b. right entorhinal cortex.

172

Heightened sensitivity to a neurotransmitter after the destruction of an incoming axon is known as:
a. axon supersensitivity
b. disuse supersensitivity
c. enervation supersensitivity
d. denervation supersensitivity

d. denervation supersensitivity

173

____ helps compensate for decreased axon input.
a. Axon supersensitivity
b. Disuse supersensitivity
c. Enervation supersensitivity
d. Denervation supersensitivity

d. Denervation supersensitivity

174

Damage to some of the axons that innervate a given structure may give rise to:
a. collateral sprouting, but not denervation supersensitivity.
b. denervation supersensitivity, but not collateral sprouting.
c. both collateral sprouting and denervation supersensitivity.
d. neither collateral sprouting nor denervation supersensitivity.

c. both collateral sprouting and denervation supersensitivity.