Seeley's Anatomy & Physiology 11th ed Chapter 11

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5. There are _____ pairs of cranial nerves and _____ pairs of spinal nerves.

12; 31

synaptic cleft

130. The figure is a process figure of the chemical synapse. What does "D" represent?

postsynaptic membrane

131. The figure is a process figure of the chemical synapse. What does "E" represent?

1. The nervous system

A. monitors internal and external stimuli. B. transmits information in the form of action potentials. C. interprets or assesses information. D. maintains homeostasis. E. All of these choices are correct.

80. The speed of an action potential depends upon

A. whether an axon is myelinated or not myelinated. B. thickness of the myelin sheath. C. the diameter of the axon. D. All of the choices are correct.

70. Each voltage-gated Na+ ion channel has two voltage sensitive gates: an activation gate and an inactivation gate. Which of the following would occur during depolarization?

Both activation and inactivation gates are open.

Pathways that allow different parts of the nervous system to affect the activity of a neuron.

Convergent pathway

46. Gray matter consists of bundles of myelinated axons.

FALSE

105. A person who has seizures might have a deficit of which of the following?

GABA

160. Identify the statement that best differentiates gray matter and white matter.

Gray matter consists of cell bodies and dendrites whereas white matter consists mostly of myelinated axons

Oscillating (reverberating) circuit

Important in functions that are periodically active such as the sleep/wake cycle and respiration.

54. In hyperpolarization

K+ ions tend to diffuse out of the cell.

26. Which of the following statements regarding neuroglia is false?

Neuroglia produce action potentials for skeletal muscles.

Important in functions that are periodically active such as the sleep/wake cycle and respiration.

Oscillating (reverberating) circuit

175. Convergent pathway

Pathways that allow different parts of the nervous system to affect the activity of a neuron.

Divergent pathway

Pathways that allow one part of the nervous system to affect more than one part of the nervous system.

166. Identify the correct sequence of information in a chemical synapse.

Presynaptic terminal; synaptic cleft; postsynaptic membrane

88. Why isn't an action potential transmitted from a postsynaptic membrane to a presynaptic terminal?

Presynaptic terminals have no acetylcholine receptors.

32. Schwann cells differ from oligodendrocytes in which of the following ways?

Schwann cells form a myelin sheath around a portion of only one axon, while oligodendrocytes can surround portions of several axons.

176. True or False: The nervous system and the endocrine system are the major control systems of the body.

TRUE

45. Gray matter has little myelination, whereas white matter has abundant myelination.

TRUE

True or False: The nervous system and the endocrine system are the major control systems of the body.

TRUE

112. If five action potentials arrive at the same synapse in very close succession, which of the following would occur?

Temporal summation occurs.

99. Action potentials at a chemical synapse

travel from presynaptic terminal to presynaptic membrane.

51. A change in the resting membrane potential has the following characteristics (non-propagated, graded, can summate). This type of change can

be a local potential and a consequence of an increase in the permeability to Na+.

24. Neurons that have a single axon and a single dendrite are

bipolar.

109. A local anesthetic such as Novocaine decreases membrane permeability to Na+ ions. The use of this anesthetic will

block sensory input into the CNS.

77. The strength of a stimulus is communicated through

both the frequency and the length of time action potentials are produced.

98. The function of acetylcholinesterase is to

breakdown acetylcholine in the synapse.

41. White matter is composed of

bundles of myelinated axons.

100. What ion is necessary for the release of neurotransmitter from synaptic vesicles?

calcium

57. Voltage-gated sodium channels are sensitive to changes in the extracellular concentration of

calcium ions.

89. Neurotransmitters

cause the production of action potentials in the postsynaptic membrane.

37. Which of the following is NOT true of reactive astrocytosis?

causes the spread of inflammation

15. Protein synthesis in neurons occurs in

cell bodies or soma.

156. Protein synthesis in neurons occurs in

cell bodies or soma.

73. The absolute refractory period assures

completion of repolarization before another action potential.

9. The autonomic nervous system

has two sets of neurons in a series.

Matching: higher inside cell

concentration of potassium

Matching: higher outside cell

concentration of sodium and chloride

114. When two or more presynaptic neurons synapse with a single postsynaptic neuron in the CNS, a(n) _______ pathway is formed.

convergent

18. Axons

have a distal portion that branches to form the presynaptic terminals.

93. Receptor molecules in synapses

have a high degree of specificity.

150. ____________ are processes that conduct electric signals toward the cell body.

dendrites

163. Identify the phases of an action potential.

depolarization hyperpolarization repolarization

94. Receptor molecules

determine whether a neurotransmitter will be excitatory or inhibitory.

14. The enteric nervous system consists of plexuses within the walls of the

digestive tract.

115. Sensory neurons carrying action potentials from pain receptors synapse within the spinal cord with interneurons. These interneurons synapse with motor neurons leading back to an effector and ascending neurons that carry action potentials toward the brain. This is an example of a(n) _____ pathway.

divergent

107. An inhibitory postsynaptic potential (IPSP) can result from the

either influx of chloride or outflow of potassium ions.

167. Synapses in which gap junctions allow ions to diffuse quickly from cell to cell are called ______ synapses.

electrical

83. Gap junctions are functional __________ synapses.

electrical

92. Monamine oxidase inhibitors (MAO inhibitors)

enhance the binding of norepinephrine to its receptors.

154. Cerebrospinal fluid is produced by ____________ cells.

ependymal

29. Hydrocephaly is a condition whereby cerebrospinal fluid accumulates around the brain. What supportive cells continue CSF production despite it backing up in the subarachnoid space?

ependymal cells

171. When a neuron releases a neuromodulator that _____ the release of neurotransmitters from another neuron, this is called presynaptic facilitation.

facilitation

Matching: oligodendrocyte

form myelin sheath around axons in CNS

Matching: Schwann cell

form myelin sheath around part of the axon in the PNS

76. A neuron is receiving a stimulus which gets stronger and stronger. The result is

frequency of occurrence of action potentials increases.

40. Action potentials are conducted more rapidly when transmission is

from node to node on a myelinated axon.

148. ____________ are collections of neuron cell bodies located outside of the central nervous system.

ganglia

178. Groups of related nerve cell bodies located outside of the central nervous system are called _____.

ganglia

6. Cell bodies of the peripheral nervous system are located in

ganglia.

102. What inhibitory neurotransmitter is blocked in strychnine poisoning?

glycine

49. Mr. Miller has been hospitalized for the flu. The flu virus increases membrane permeability to potassium. You would expect his cells to

hyperpolarize.

110. An IPSP is inhibitory because it

hyperpolarizes the postsynaptic membrane.

74. The absolute refractory period ends when

inactivation gates of voltage-gated Na+ ion channels reopen.

170. When a neuron releases a neuromodulator that _____ the release of neurotransmitters from another neuron, this is called presynaptic facilitation.

increases

58. A local potential

increases or decreases in direct proportion to the stimulus strength.

Matching: astrocytes

influence function of blood-brain barrier

81. Local hyperpolarization in a synapse is called a(an)

inhibitory postsynaptic potential.

87. Damage to a postsynaptic membrane would

interfere with the ability to respond to neurotransmitter.

21. A neuron within the central nervous system that carries action potentials from one neuron to another is called a(n)____________.

interneuron

95. A neuromodulator

is a substance released from neurons that influences the sensitivity of neurons to neurotransmitters.

67. The opening of more and more Na+ ion channels during depolarization

is an example of a positive feedback cycle.

72. During the absolute refractory period, the cell

is insensitive to further stimulation.

11. The central nervous system

is the site for processing information.

50. For the resting membrane potential, increasing the sodium ion concentration in the ECF results in

little change in membrane potential.

106. In an EPSP (excitatory postsynaptic potential), there is a

local depolarization.

59. A change in resting membrane potential confined to a small area is called a(n)

local potential.

Matching: microglia

macrophages in CNS

91. Rapid removal or destruction of neurotransmitter in the synaptic cleft

may affect the ability of the postsynaptic membrane to generate action potentials.

Matching: depolarization

membrane becomes more positive when sodium ions diffuse into cell

153. ____________ are neuroglia cells that are macrophages.

microglia

33. Which of the following is mismatched?

microglia - provide support for the neuron cell body

97. The same neurotransmitter binds to a postsynaptic cell but produces a variety of different effects. What does this mean?

The postsynaptic cell is expressing different types of receptors for the same neurotransmitter.

48. Which of the following is true?

The resting membrane potential is proportional to the tendency for K+ to diffuse out of the cell.

Matching: large molecules trapped inside cell

negatively charged proteins

42. If you cut bundles of axons and their myelin sheaths in the PNS, you cut

nerves.

169. Compounds classified as ______ alter synaptic transmission by changing neurotransmitter receptor numbers or affecting the breakdown and/or removal of neurotransmitter.

neuromodulators

103. Viagra is used to treat erectile dysfunction by prolonging the effects of _____ on blood vessels.

nitric oxide (NO)

35. Gaps or interruptions in the myelin sheath are called

nodes of Ranvier.

43. Clusters of gray matter deep within the brain are called

nuclei.

Matching: repolarization

return to the resting membrane potential

116. Neurons arranged in a circular pathway form

reverberating circuits.

155. Action potentials are conducted rapidly from one node of Ranvier to the next in a process called ____________ conduction.

saltatory

147. The nervous system has two subdivisions - the central nervous system and the ____________ nervous system.

peripheral

The nervous system has two subdivisions - the central nervous system and the ____________ nervous system.

peripheral

Matching: postassium ions

plasma membrane is more permeable to this ion because of leak ion channels

60. Low levels of ___ can have dire consequences on the functioning of neurons because of its role in membrane repolarization.

potassium ions

86. Neurotransmitters are released from the

presynaptic terminal.

20. Synaptic vesicles contain neurotransmitters and are present in the

presynaptic terminals.

Matching: ependymal cells

produce cerebrospinal fluid

27. The blood-brain barrier

protects neurons from toxic substances in the blood.

25. Neurons in the skin that are responsible for detecting pain are

pseudo-unipolar.

104. A decrease in the number of voltage-gated Ca2+ ion channels in the presynaptic terminal would

reduce or inhibit transmission across the synapse.

38. Which of the following is NOT a neuroglia of the CNS?

satellite cells

39. What type of neuroglial cells provide support and nutrition to sensory ganglia in the PNS?

satellite cells

152. Most unipolar neurons are ____________ neurons.

sensory

79. Saltatory conduction of an action potential means that

an action potential is conducted from one node of Ranvier to the next node.

64. A stimulus either causes an action potential or it doesn't. This is called

an all-or-none response.

96. When a neurotransmitter binds to its receptor and increases the permeability of the postsynaptic membrane to sodium ions,

an excitatory postsynaptic potential (EPSP) will result.

53. Which of the following events will lead to depolarization?

an increase in K+ ions in the extracellular fluid

17. Dendrites

are the input part of the neuron.

16. Nissl bodies are

areas of rough endoplasmic reticulum.

28. LouAnn is being treated for a neurological condition with a specific drug that target neurons deep within the brain. Which glial cell must be bypassed by this drug in order for it to be effective?

astrocyte

159. The division of the nervous system that transmits electrical impulses towards cardiac muscle, smooth muscle and glands is the _____; while the division of the nervous system that transmits electrical impulses towards skeletal muscle is the _____.

autonomic nervous system somatic nervous system

149. Nerve fibers are also called ____________.

axons

12. Which of the following is mismatched?

somatic nervous system - sensory division of PNS

13. The junction of a neuron with another cell is a/an

synapse.

85. The junction between two neurons is a

synapse.

65. In some cells, an afterpotential occurs because

there is prolonged, elevated permeability to potassium during repolarization.

165. In order for local potentials to trigger an action potential, the membrane must reach a level called the ______.

threshold

8. The motor (efferent) division of the peripheral nervous system

transmits impulses from the CNS to skeletal muscle.

168. Identify the mechanisms by which neuromodulators alter synaptic transmission.

-Changing neurotransmitter receptor numbers -Affecting breakdown of neurotransmitters -Affecting the removal of neurotransmitters

164. Identify the characteristics of action potentials.

-The strength of the stimulus determines the frequency of the action potentials. -They are all-or-none -They are propagated in a non-decremental fashion.

84. Arrange the events of synaptic transmission in correct sequence.

-action potential causes release of neurotransmitter -neurotransmitter diffuses across the synaptic cleft -neurotransmitter binds with receptor on postsynaptic cell -membrane permeability to sodium ions on postsynaptic cell increases -sodium ions diffuse into the cell and cause a local potential

159. The division of the nervous system that transmits electrical impulses towards cardiac muscle, smooth muscle and glands is the ___ ; while the division of the nervous system that transmits electrical impulses towards skeletal muscle is the ___

-autonomic nervous system -somatic nervous system.

177. Identify the functions of the nervous system.

-controlling muscles and glands -integrating information -receiving sensory input

163. Identify the phases of an action potential.

-depolarization -hyperpolarization -repolarization

Identify the two functional sub-divisions of the peripheral nervous system.

-motor division -sensory division

dendrites

117. Identify structure "A" on the neuron.

neuron cell body (soma)

118. Identify structure "B" on the neuron.

axon

119. Identify structure "C" on the neuron.

Schwann cell

120. Identify structure "D" on the neuron.

Node of Ranvier

121. Identify structure "E" on the neuron.

local potential

122. The figure illustrates the Action Potential. What does "A" represent?

depolarization

123. The figure illustrates the Action Potential. What does "B" represent?

repolarization

124. The figure illustrates the Action Potential. What does "C" represent?

threshold

125. The figure illustrates the Action Potential. What does "D" represent?

afterpotential

126. The figure illustrates the Action Potential. What does "E" represent?

voltage-gated calcium channel

127. The figure is a process figure of the chemical synapse. What does "A" represent?

synaptic vesicle

128. The figure is a process figure of the chemical synapse. What does "B" represent?

presynaptic terminal

129. The figure is a process figure of the chemical synapse. What does "C" represent?

52. Which of the following statements accurately describe events that occur as a result of a local potential reaching threshold?

A positive feedback cycle develops in which depolarization causes activation gates of Na+ ion channels to open.

68. Which of the following statements regarding voltage-gated K+ channels is true?

A. These channels have only one gate. B. These channels open more slowly than Na+ channels. C. Once open, these channels remain open until repolarization is complete. D. These channels are specific for potassium. E. All of these statements are true.

90. Neurotransmitter is being released at a synapse. Which of the following occurs last?

An action potential is produced in the postsynaptic membrane.

63. Which of the following events is NOT a characteristic of an action potential?

As sodium ions enter, the inside of the plasma membrane becomes more negative.

56. Which of the following situations occurs in electrically excitable cells?

Depolarization causes voltage-gated sodium ion channels to open.

Pathways that allow one part of the nervous system to affect more than one part of the nervous system.

Divergent pathway

36. Which of the following is NOT true about astrocytes?

They can aid in the regeneration of injured neurons.

34. Which of the following is true?

Unmyelinated axons rest in invaginations of Schwann cells or oligodendrocytes.

Matching: Resting Membrane Potential

a charge difference across the plasma membrane when the cell is in an unstimulated state

Matching: Action Potential

a larger change in resting membrane potential that spreads over entire surface of a cell

71. If the ECF around a nerve cell is replaced with an isotonic saline solution that contains potassium ions and other solutes at concentrations very close to the ECF concentrations of a normal cell, the result is

a resting membrane potential close to its normal value.

Matching: Local Potential

a small change in the resting membrane potential confined to a small area

101. What is the only neurotransmitter released at the neuromuscular junction?

acetylcholine

158. (?)The division of the peripheral nervous system that transmits electrical impulses from sensory receptors to the CNS is the ___division, while the ___ division of the peripheral nervous system transmits electrical impulses from the CNS toward muscles and glands.

afferent efferent

2. Which of the following is responsible for problem-solving skills?

central nervous system

174. Identify the type of synapse that includes a presynaptic cell, synaptic cleft, and postsynaptic cell.

chemical

172. The respiratory center of the brain (taking into account input from chemoreceptors, pulmonary stretch receptors and higher centers of the brain to determine respiratory output) is an example of a ______ circuit.

converging

7. The sensory (afferent) division of the peripheral nervous system

conveys action potentials to the CNS.

161. The gray matter of the cerebrum is composed of neuron cell bodies and makes up both the ______ and the ______.

cortex ; deep cerebral nuclei

4. The peripheral nervous system includes the

cranial nerves.

108. Enkephalins produce presynaptic inhibition in neurons transmitting pain signals. Increased levels of enkephalins will

decrease awareness of pain.

30. Fran has a microbial infection attacking his brain. Which cell type would you expect to proliferate and be most active during this time?

microglial cells

157. Identify the two functional sub-divisions of the peripheral nervous system.

motor division sensory division

151. A neuron with several dendrites and a single axon would be called a ____________ neuron.

multipolar

23. The motor neurons responsible for making a fist are

multipolar.

62. An action potential

occurs when the local potential reaches threshold level.

31. Multiple sclerosis is a neurological disorder in which myelin sheaths in the CNS are destroyed. Which of the following neuroglial cells is being damaged in multiple sclerosis?

oligodendrocyte

78. Continuous conduction of an action potential means that

one action potential stimulates the production of a new action potential at the adjacent site.

66. When repolarization of a neuron is complete, the

original polarity of the neuron is restored.

173. Which type of circuit is associated with complex neuronal processes, such as solving mathematical equations?

parallel after-discharge

10. Digestion of food is regulated by the

parasympathetic division of the ANS.

22. A neuron that conducts pain sensations to the central nervous system would be classified as a(n)

sensory or afferent neuron.

69. During depolarization of the plasma membrane,

sodium ions move rapidly into the cell.

61. Depolarization of the nerve cell membrane occurs when there is a rapid influx (inflow) of

sodium ions.

Matching: requires ATP

sodium/potassium pump

111. When two action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron,

spatial summation occurs.

3. The central nervous system includes the

spinal cord.

44. Gray matter on the surface of the brain is/are called

the cortex.

55. If the charge difference across the plasma membrane is decreased,

the membrane potential is more positive.

75. A series of local potentials causes the membrane potential to move to -80 mV. Predict the result.

the neuron is hyperpolarized

113. Suppose both excitatory and inhibitory neurons synapse with a single postsynaptic neuron. What determines if an action potential is initiated in the postsynaptic neuron?

the number of EPSPs in relation to the number of IPSPs

82. Chemical synapses are characterized by

the release of neurotransmitter by the presynaptic terminal.

19. Axons contain

the trigger zone.

47. The plasma membrane of a neuron is more permeable to potassium ions because

there are more leak ion channels for K+ than Na+.

162. Nervous tissue of the CNS that is composed primarily of myelinated axons is often referred to as ______ matter.

white


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