A&P Chapter 11

9. The autonomic nervous system A. stimulates skeletal muscle contractions. B. has two sets of neurons in a series. C. is involved in problem solving. D. is under voluntary control. E. does not include the central nervous system.

B has two sets of neurons in a series

17. Axons contain A. the trigger zone. B. foot processes. C. Nissl bodies. D. the soma. E. the rough endoplasmic reticulum.

A the trigger zone

89. A person who has seizures might have a deficit of which of the following? A. GABA B. dopamine C. glutamate D. serotoninP E. histamine

A. GABA

20. A neuron that conducts pain sensations to the central nervous system would be classified as a(n) A. motor neuron. B. sensory or afferent neuron. C. efferent neuron. D. association neuron. E. interneuron.

B sensory or afferent neuron

109. The figure illustrates the Action Potential. What does "D" represent? A. repolarization B. depolarization C. local potential D. threshold E. afterpotential

threshhold

126. microglia ________________________________________

B. macrophages in CNS

100. Neurons arranged in a circular pathway form A. neuromotor junctions. B. oscillatory circuits. C. spatial pathways. D. temporal circuits. E. circulating pathways.

B. oscillatory circuits.

88. A decrease in the number of voltage-gated Ca++ ion channels in the presynaptic terminal would A. enhance transmission across the synapse. B. reduce or inhibit transmission across the synapse. C. have no effect on transmission across the synapse. D. alter receptors on the postsynaptic membrane. E. increase exocytosis.

B. reduce or inhibit transmission across the synapse.

5. There are _____ pairs of cranial nerves and _____ pairs of spinal nerves. A. 10; 30 B. 31; 12 C. 12; 31 D. 30; 10 E. 12; 32

C 12; 31

13. Protein synthesis in neurons occurs in A. axons. B. dendrites. C. cell bodies or soma. D. terminal boutons. E. node of Ranvier.

C Cell bodies or soma

4. The peripheral nervous system includes the A. brain. B. spinal cord. C. cranial nerves. D. blood-brain barrier. E. cerebellum.

C Cranial Nerves

27. Which of the following substances must pass through the blood-brain barrier in order for neurons to survive? A. nicotine B. collagen C. glucose D. dopamine E. insulin

C Glucose

10. Digestion of food is regulated by the A. sensory division. B. sympathetic division of the ANS. C. parasympathetic division of the ANS. D. somatic nervous system. E. None of these choices is correct.

C Parasympathetic division of the ANS

8. The motor (efferent) division of the peripheral nervous system A. is a division of the CNS. B. regulates the digestion of food. C. transmits impulses from the CNS to skeletal muscle. D. has nerve cell bodies located in ganglia near the spinal cord and brain. E. detects a stimulus.

C Transmits impulses from the CNS to skeletal muscle

16. Axons A. contain the nucleus. B. are numerous extensions from each neuron. C. do not have a trigger zone. D. have a distal portion that branches to form the presynaptic terminals or terminal boutons. E. do not have a resting membrane potential.

D Have a distal portion that branches to form the presynaptic terminals or terminal boutons

40. Mr. Miller has been hospitalized for the flu. The flu virus increases membrane permeability to potassium. You would expect his cells to A. depolarize. B. repolarize. C. isopolarize. D. hyperpolarize. E. hypopolarize.

D Hyperpolarize

18. Synaptic vesicles contain neurotransmitters and are present in the A. dendrites. B. cell body. C. axolemma. D. presynaptic terminals or terminal boutons. E. trigger zone.

D Presynaptic terminals our terminal boutons

106. The figure illustrates the Action Potential. What does "A" represent? A. repolarization B. depolarization C. local potential D. threshold E. afterpotential

Local potential

107. The figure illustrates the Action Potential. What does "B" represent? A. repolarization B. depolarization C. local potential D. threshold E. afterpotential

depolarization

110. The figure illustrates the Action Potential. What does "E" represent? A. repolarization B. depolarization C. local potential D. threshold E. depolarization

depolarization

138. Cerebrospinal fluid is produced by ____________ cells.

ependymal

50. A change in resting membrane potential confined to a small area is called a(n) A. local potential. B. action potential. C. summated potential. D. after potential. E. resting membrane potential.

A. local potential.

80. Rapid removal or destruction of neurotransmitter in the synaptic cleft A. may affect the ability of the postsynaptic membrane to generate action potentials. B. generates local potentials in the presynaptic terminal. C. is necessary for synaptic transmission. D. may lead to action potentials. E. may stop exocytosis.

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

32. Which of the following is mismatched? A. microglia - provide support for the neuron cell body B. astrocytes - blood-brain barrier C. oligodendrocytes - form myelin sheaths D. ependymal cells - produce cerebrospinal fluid E. ependymal cells - choroid plexus

A. microglia - provide support for the neuron cell body

53. An action potential A. occurs when the local potential reaches threshold level. B. propagates across the plasma membrane in a decremental fashion. C. has no repolarization phase. D. is an example of negative feedback. E. cannot transmit information.

A. occurs when the local potential reaches threshold level.

67. Chemical synapses are characterized by A. the release of neurotransmitter by the presynaptic terminal. B. protein channels that connect the pre- and postsynaptic cells. C. the presence of receptors for neurotransmitters on the presynaptic terminal. D. the absence of gap junctions. E. receptors located only on the presynaptic terminal.

A. the release of neurotransmitter by the presynaptic terminal.

86. The same neurotransmitter may produce different effects on neurons because of differences in the A. type of receptors on the postsynaptic membranes of neurons. B. strength of the action potential. C. amount of neurotransmitter. D. size of the neurons. E. potassium channels.

A. type of receptors on the postsynaptic membranes of neurons.

96. If five action potentials arrive at the same synapse in very close succession, which of the following would occur? A. The direction of the action potential is reversed. B. Temporal summation occurs. C. Spatial summation occurs. D. Hyperpolarization occurs. E. Depolarization always occurs.

B. Temporal summation occurs.

122. Resting Membrane Potential ________________________________________

B. a change difference across the plasma membrane when the cell is in an unstimulated state

22. Neurons that have a single axon and a single dendrite are A. unipolar. B. bipolar. C. multipolar. D. pseudopolar. E. monopolar.

B. bipolar

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

Ganglia

37. If you cut bundles of axons and their myelin sheaths in the PNS, you cut A. ganglia. B. nuclei. C. nerves. D. gray matter. E. nerve tracts.

Nerves

133. Nerve fibers are also called ____________.

axons

73. When the local potential returns quickly to resting membrane potential even though the stimulus continues, _____ is occurring. A. an afterpotential B. ligand gating C. accommodation D. a sodium influx E. acclimation.

c accommodation

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

dendrites

137. ____________ are neuroglia cells that are macrophages.

microglia

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

multipolar

102. Identify structure "B" on the neuron. A. Schwann cell B. Node of Ranvier C. neuron cell body (soma) D. dendrites E. axon

neuron cell body (soma)

108. The figure illustrates the Action Potential. What does "C" represent? A. repolarization B. depolarization C. local potential D. threshold E. afterpotential

repolarization

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

saltatory

136. Most unipolar neurons are ____________ neurons.

sensory

112. The figure is a process figure of the chemical synapse. What does "B" represent? A. postsynaptic membrane B. synaptic cleft C. synaptic vesicle D. voltage-gated calcium channel E. presynaptic terminal

synaptic vesicle

44. Which of the following events will lead to depolarization? A. an increase in K+ ions in the extracellular fluid B. a decrease in K+ ions in the extracellular fluid C. an increase in the rate of diffusion of K+ ions from cells D. an increase in Na+ ions in the extracellular fluid E. None of these events would cause depolarization.

. None of these events would cause depolarization.

104. Identify structure "D" on the neuron. A. Schwann cell B. Node of Ranvier C. neuron cell body (soma) D. dendrites E. axon

. Schwann cell

15. Dendrites A. are the input part of the neuron. B. conduct action potentials away from the cell body. C. are generally long and unbranched. D. form synapses with the microglia. E. contain the trigger zone.

A Are the input part of the neuron

2. Which of the following is responsible for problem-solving skills? A. central nervous system B. peripheral nervous system C. somatic nervous system D. autonomic nervous system E. None of these choices is correct.

A Central Nervous System

6. Cell bodies of the peripheral nervous system are located in A. ganglia. B. Schwann cells. C. the motor division. D. the sensory division. E. nerves.

A Ganglia

33. Which of the following is true? A. In saltatory conduction, electrical charges flow from node to node. B. Myelination will not influence the speed of conduction of action potentials. C. The myelin sheath inhibits the flow of electrical charges at nodes. D. The myelin sheath is a protein wrapping. E. The myelin sheath does not electrically insulate the axons from one another.

A In saltatory conduction, electrical charges flow from node to node

26. A neuroglial cell that is a major component of the blood-brain barrier is the A. astrocyte. B. microglial cell. C. oligodendrocyte. D. ependymal cell. E. macrophage.

A astrocyte

35. Action potentials are conducted more rapidly when transmission is A. from node to node on a myelinated axon. B. on a small diameter axon. C. on an unmyelinated axon. D. from internode to internode. E. from internode to node on a myelinated axon.

A from node to node o na myelinated axon

11. The central nervous system A. is the site for processing information. B. initiates visual and auditory stimuli. C. consists of 43 pairs of nerves. D. is totally involuntary. E. does not interact with the peripheral nervous system.

A is the site for processing information

45. In hyperpolarization A. K+ ions tend to diffuse out of the cell. B. the plasma membrane's permeability to K+ decreases. C. the resting membrane potential moves closer to zero. D. Na+ ions enter the cell in large numbers. E. the resting membrane potential becomes more positive.

A. K+ ions tend to diffuse out of the cell.

77. Why isn't an action potential transmitted from a postsynaptic membrane to a presynaptic terminal? A. Presynaptic terminals have no acetylcholine receptors. B. Presynaptic neurons do not have a resting membrane potential. C. Acetylcholine can only diffuse in one direction across the synaptic cleft. D. Synaptic vesicles in the postsynaptic membrane are inactive. E. Acetylcholine is destroyed too fast.

A. Presynaptic terminals have no acetylcholine receptors.

125. Local Potential ________________________________________

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

55. A stimulus either causes an action potential or it doesn't. This is called A. an all-or-none response. B. a graded response. C. a latent period response. D. a relative refractory response. E. a local response.

A. an all-or-none response.

93. A local anesthetic such as Novocaine decreases membrane permeability to Na+ ions. The use of this anesthetic will A. block sensory input into the CNS. B. enhance the development of EPSPs. C. cause RMP to move closer to threshold. D. cause Cl- ions to enter cells instead of Na+ ions. E. depolarize the cell.

A. block sensory input into the CNS.

118. higher inside cell ________________________________________

A. concentration of potassium

98. When two or more presynaptic neurons synapse with a single postsynaptic neuron in the CNS, a(n) _______ pathway is formed. A. convergent B. divergent C. oscillatory D. somatic E. sensory

A. convergent

66. The absolute refractory period ends when A. inactivation gates of voltage-gated Na+ ion channels reopen. B. activation gates of voltage-gates Na+ ion channels reopen. C. the sodium-potassium exchange pump stops. D. voltage-gated K+ channels open. E. None of these choices is correct.

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

129. astrocytes ________________________________________

A. influence function of blood-brain barrier

60. During depolarization of the plasma membrane, A. sodium ions move rapidly into the cell. B. potassium ions move rapidly out of the cell. C. membrane permeability to sodium ions decreases. D. the outside of the cell becomes positively charged relative to the inside. E. sodium ions move rapidly out of the cell.

A. sodium ions move rapidly into the cell.

103. Identify structure "C" on the neuron. A. Schwann cell B. Node of Ranvier C. neuron cell body (soma) D. dendrites E. axon

Axon

36. White matter is composed of A. ganglial sheaths. B. bundles of myelinated axons. C. collections of nerve cell bodies. D. bundles containing both myelinated axons and nerve cell bodies. E. collections of unmyelinated axons.

B Bundles of myelinated axons

7. The sensory (afferent) division of the peripheral nervous system A. transmits action potentials to sensory organs. B. conveys action potentials to the CNS. C. stimulates glands to release hormones. D. stimulates muscle contractions. E. does not involve sensory receptors.

B Conveys action potentials to the CNS

3. The central nervous system includes the A. ganglia. B. spinal cord. C. spinal nerves. D. cranial nerves. E. sensory receptors.

B Spinal Cord

74. The junction between two neurons is a A. ganglia. B. synapse. C. fascicle. D. node of Ranvier. E. neuromuscular junction.

B Synapse

62. Burn patients experience the destruction of cells and the release of cellular contents into the ECF. Burn patients are more likely to suffer from which of the following conditions? A. action potentials with exaggerated amplitudes B. tachycardia (a rapid heart rate) C. hyperpolarization of nerves and muscle fibers D. inability of neurons to stimulate muscle fibers E. action potentials with exaggerated amplitudes and tachycardia (a rapid heart rate)

B Tachycardia

29. Microglia A. are part of the blood-brain barrier. B. are phagocytic cells in the CNS. C. produce cerebrospinal fluid. D. form myelin sheaths. E. are part of the choroid plexus.

B are phagocytic cells in the CNS

54. Which of the following events is NOT a characteristic of an action potential? A. The plasma membrane becomes highly permeable to sodium ions and depolarization results. B. As sodium ions enter, the inside of the plasma membrane becomes more negative. C. At the peak of depolarization, sodium channels begin to close and potassium channels open. D. In repolarization, potassium ions flow out of the cell. E. Action potentials occur according to the all-or-none principle.

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

65. The absolute refractory period assures A. prolonged depolarization during the action potential. B. completion of repolarization before another action potential. C. that no after-potential occurs. D. reversal of the direction of propagation of the action potential. E. that the stimulus is strong enough to elicit a response.

B. completion of repolarization before another action potential.

119. higher outside cell ________________________________________

B. concentration of sodium and chloride

92. Enkephalins produce presynaptic inhibition in neurons transmitting pain signals. Increased levels of enkephalins will A. increase awareness of pain. B. decrease awareness of pain. C. increase amount of pain. D. decrease amount of pain. E. have no effect on awareness or amount of pain.

B. decrease awareness of pain.

99. 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. A. convergent B. divergent C. oscillatory D. sensory E. bifurcated

B. divergent

68. Gap junctions are functional __________ synapses. A. chemical B. electrical C. potential D. intracellular E. neuromuscular

B. electrical

58. The opening of more and more Na+ ion channels during depolarization A. is the result of the sodium-potassium exchange pump. B. is an example of a positive feedback cycle. C. is possible only if K+ channels remain closed. D. is the cause of the afterpotential. E. is an example of a negative feedback cycle.

B. is an example of a positive feedback cycle.

64. During the absolute refractory period, the cell A. generates many local potentials. B. is insensitive to further stimulation. C. responds to even weak stimuli. D. reverses the direction of the action potential. E. is very sensitive

B. is insensitive to further stimulation.

46. If the charge difference across the plasma membrane is decreased, A. the potential difference across the plasma membrane does not change. B. the membrane potential is more positive. C. the change is called hyperpolarization. D. negative proteins can leave the cell. E. the membrane potential is more negative.

B. the membrane potential is more positive.

38. The plasma membrane of a neuron is more permeable to potassium ions because A. of its positive electrical charge. B. there are more non-gated channels for K+ than Na+. C. protein molecules cannot exit through the cell membrane. D. calcium ions block Na+ and Cl- channels. E. there are more non-gated channels for Na+ than K+.

B. there are more non-gated channels for K+ than Na+.

56. In some cells, an afterpotential occurs because A. the sodium ions continue to enter the cell after depolarization is finished. B. there is prolonged, elevated permeability to potassium during repolarization. C. the sodium-potassium pump is actively exchanging ions across the membrane. D. the extracellular Na+ ion concentration is reduced. E. the permeability to sodium continues longer than necessary.

B. there is prolonged, elevated permeability to potassium during repolarization.

21. The motor neurons responsible for making a fist are A. unipolar. B. bipolar. C. multipolar. D. pseudopolar. E. None of these choices is correct.

C multipolar

30. 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? A. astrocyte B. microglial cell C. oligodendrocyte D. ependymal cell E. Schwann cells

C oligodendrocyte

79. Neurotransmitter is being released at a synapse. Which of the following occurs last? A. Calcium ions enter the presynaptic terminal. B. Synaptic vesicles release neurotransmitter by exocytosis. C. An action potential is produced in the postsynaptic membrane. D. Neurotransmitter flows rapidly across the synaptic cleft. E. Neurotransmitter binds with the receptor on the postsynaptic membrane.

C. An action potential is produced in the postsynaptic membrane.

61. 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? A. Activation gates are open; inactivation gates are closed. B. Activation gates are closed; inactivation gates are open. C. Both activation and inactivation gates are open. D. Both activation and inactivation gates are closed. E. None of these events occurs during depolarization.

C. Both activation and inactivation gates are open.

47. Which of the following situations occurs in electrically excitable cells? A. When Na+ ion channels open, K+ ion channels close. B. The sodium-potassium exchange pump moves sodium into the cell. C. Depolarization causes voltage-gated sodium ion channels to open. D. Ligand-gated sodium ion channels are opened by high extracellular calcium levels. E. Proteins tend to diffuse out of the cell.

C. Depolarization causes voltage-gated sodium ion channels to open.

24. Which of the following statements regarding neuroglia is false? A. Neuroglia serve as the major supporting tissue in the CNS. B. Neuroglia form part of the blood-brain barrier. C. Neuroglia produce action potentials for skeletal muscles. D. Neuroglia form myelin sheaths around some axons. E. Neuroglia produce cerebrospinal fluid.

C. Neuroglia produce action potentials for skeletal muscles.

39. Which of the following is true? A. The resting plasma membrane is more permeable to Na+ than K+. B. The resting membrane potential never reaches an equilibrium point. C. The resting membrane potential is proportional to the tendency for K+ to diffuse out of the cell. D. Negatively charged Cl- ions are attracted by negative charges in the cell. E. The purpose of the sodium-potassium exchange pump is to create the resting membrane potential.

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

123. Action Potential ________________________________________

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

85. When a neurotransmitter binds to its receptor and increases the permeability of the postsynaptic membrane to sodium ions, A. the membrane will be hyperpolarized. B. more chloride ions will also diffuse into the cell. C. an excitatory postsynaptic potential (EPSP) will result. D. the membrane will become impermeable to potassium ions. E. the sodium ions diffuse out of the cell.

C. an excitatory postsynaptic potential (EPSP) will result.

81. Monamine oxidase inhibitors (MAO inhibitors) A. prevent synaptic transmission. B. enhance the breakdown of norepinephrine. C. enhance the binding of norepinephrine to its receptors. D. prevent the release of norepinephrine by the presynaptic terminal. E. have no effect on the action of norepinephrine

C. enhance the binding of norepinephrine to its receptors.

72. As the strength of a stimulus is increased, the A. amplitude of the action potential increases. B. duration of the action potential increases. C. frequency of occurrence of action potentials increases. D. resonance of action potentials increases. E. height of the action potentials increases.

C. frequency of occurrence of action potentials increases.

82. Receptor molecules in synapses A. tend to concentrate on presynaptic terminals. B. bind irreversibly with neurotransmitter. C. have a high degree of specificity. D. serve as channel proteins. E. can bind to any molecule in the synapse.

C. have a high degree of specificity.

69. Local hyperpolarization in a synapse is called a(an) A. excitatory postsynaptic potential. B. resting membrane potential. C. inhibitory postsynaptic potential. D. gap junction potential. E. action potential.

C. inhibitory postsynaptic potential.

116. large molecules trapped inside cell ________________________________________

C. negatively charged proteins

75. Neurotransmitters are released from the A. epineurium. B. synaptic cleft. C. presynaptic terminal. D. postsynaptic membrane. E. calcium channels.

C. presynaptic terminal.

94. An IPSP is inhibitory because it A. changes the threshold of the neuron. B. hyperpolarizes the postsynaptic membrane. C. prevents Ca++ entry into the presynaptic terminal. D. reduces the amount of neurotransmitter released by the presynaptic terminal. E. depolarizes the postsynaptic membrane.

C. prevents Ca2+ entry into the presynaptic terminal.

130. ependymal cells ________________________________________

C. produce cerebrospinal fluid

95. When two action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron, A. the direction of the action potential is reversed. B. temporal summation occurs. C. spatial summation occurs. D. hyperpolarization occurs. E. threshold is never reached.

C. spatial summation occurs.

71. A stimulus that results in a local potential that does not reach threshold is called a A. threshold stimulus. B. maximal stimulus. C. subthreshold stimulus. D. supramaximal stimulus. E. local stimulus.

C. subthreshold stimulus.

31. Schwann cells differ from oligodendrocytes in which of the following ways? A. Schwann cells form myelin; oligodendrocytes do not. B. Oligodendrocytes are only found in the PNS; Schwann cells are only found in the CNS. C. Schwann cells form sheaths around several axons, while oligodendrocytes form sheaths around only one axon. D. Schwann cells form a myelin sheath around a portion of only one axon, while oligodendrocytes can surround portions of several axons. E. None of these choices are true differences.

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

14. Nissl bodies are A. part of a dendrite. B. also called gemmules. C. lipid droplets. D. areas of rough endoplasmic reticulum. E. part of the Golgi apparatus.

D areas of rough endoplasmic reticulum

41. For the resting membrane potential, increasing the sodium ion concentration in the ECF results in A. hyperpolarization. B. depolarization. C. hypopolarization. D. little change in membrane potential. E. There is not enough information to determine the results.

D little change in membrane potential

34. Gaps or interruptions in the myelin sheath are called A. internodes. B. tight junctions. C. neurofilaments. D. nodes of Ranvier. E. gap junctions.

D nodes of Ranvier

63. 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. no resting membrane potential. B. hyperpolarized membrane. C. depolarized membrane. D. a resting membrane potential close to its normal value. E. None of these choices is correct.

D. a resting membrane potential close to its normal value.

78. Neurotransmitters A. stimulate presynaptic terminals. B. remain in the synaptic cleft for long periods of time. C. bind irreversibly to the receptor molecules of the postsynaptic membrane. D. cause the production of action potentials in the postsynaptic membrane. E. do not affect membrane channels in the postsynaptic membrane.

D. cause the production of action potentials in the postsynaptic membrane.

83. Receptor molecules A. are nonspecific. B. are always lipids. C. attach to the synaptic cleft. D. determine whether a neurotransmitter will be excitatory or inhibitory. E. are not attached to ligand-gated channels.

D. determine whether a neurotransmitter will be excitatory or inhibitory.

128. oligodendrocyte ________________________________________

D. form myelin sheath around axons in CNS

49. A local potential A. does not occur until threshold. B. transmits information from one cell to another. C. might be a depolarization event but cannot be a hyperpolarization event. D. increases or decreases in direct proportion to the stimulus strength. E. does not alter resting membrane potential.

D. increases or decreases in direct proportion to the stimulus strength.

76. Damage to a postsynaptic membrane would A. increase neurotransmitter release. B. decrease the release of neurotransmitter. C. increase neurotransmitter production. D. interfere with the ability to respond to neurotransmitter. E. destroy vesicles containing neurotransmitter.

D. interfere with the ability to respond to neurotransmitter.

121. depolarization ________________________________________

D. membrane becomes more positive when sodium ions diffuse into cell

57. When repolarization of a neuron is complete, the A. neuron dies. B. neuron regenerates. C. cell no longer has a potential difference across its membrane. D. original polarity of the neuron is restored. E. neuron is no longer excitable.

D. original polarity of the neuron is restored.

25. The blood-brain barrier A. permits passage of foreign substances from the blood to the neurons. B. prohibits the transport of amino acids and glucose to the neurons. C. prohibits the removal of waste materials from the neurons. D. protects neurons from toxic substances in the blood. E. does not prevent fluctuations in the composition of the blood from affecting the functions of the brain.

D. protects neurons from toxic substances in the blood.

52. Depolarization of the nerve cell membrane occurs when there is a rapid influx (inflow) of A. potassium ions. B. chloride ions. C. calcium ions. D. sodium ions. E. proteins.

D. sodium ions.

117. requires ATP ________________________________________

D. sodium/potassium pump

97. Suppose both excitatory and inhibitory neurons synapse with a single postsynaptic neuron. What determines if an action potential is initiated in the postsynaptic neuron? A. the kind of neuron involved B. the size of the neuron involved C. whether the neuron is myelinated or non-myelinated D. the number of EPSPs in relation to the number of IPSPs E. This situation is not possible in humans.

D. the number of EPSPs in relation to the number of IPSPs

87. Action potentials at a chemical synapse travel A. from presynaptic terminal to postsynaptic membrane. B. from postsynaptic membrane to presynaptic terminal. C. back and forth from presynaptic terminal to postsynaptic membrane. D. from presynaptic terminal to presynaptic membrane. E. from postsynaptic terminal to postsynaptic membrane.

D. travel from presynaptic terminal to presynaptic membrane.

111. The figure is a process figure of the chemical synapse. What does "A" represent? A. postsynaptic membrane B. synaptic cleft C. synaptic vesicle D. voltage-gated calcium channel E. presynaptic terminal

D. voltage-gated calcium channel

101. Identify structure "A" on the neuron. A. Schwann cell B. Node of Ranvier C. neuron cell body (soma) D. dendrites E. axon

Dendrites

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.

E All of these choices are correct

12. Which of the following is mismatched? A. central nervous system - brain B. autonomic nervous system - sympathetic and parasympathetic divisions C. peripheral nervous system - spinal nerves D. somatic nervous system - sensory division of PNS E. peripheral nervous system - sensory and motor divisions

E Peripheral nervous system - sensory and motor divisions ????

28. Overproduction of cerebrospinal fluid could be the result of overactivity of the A. astrocytes. B. microglial cells. C. oligodendrocytes. D. macrophages. E. ependymal cells.

E ependymal cells

19. A neuron that carries action potentials from one neuron to another is called a(n)____________. A. motor neuron B. sensory neuron C. afferent neuron D. efferent neuron E. interneuron

E interneuron

23. Neurons in the skin that are responsible for detecting pain are A. apolar. B. unipolar. C. bipolar. D. multipolar. E. pseudopolar.

E pseudopolar

70. Arrange the events of synaptic transmission in correct sequence. (1) sodium ions diffuse into the cell and cause a local potential (2) neurotransmitter binds with receptor on postsynaptic cell (3) neurotransmitter diffuses across the synaptic cleft (4) membrane permeability to sodium ions on postsynaptic cell increases (5) action potential causes release of neurotransmitter A. 5, 2, 3, 4, 1 B. 5, 2, 3, 1, 4 C. 5, 3, 4, 1, 2 D. 5, 4, 3, 2, 1 E. 5, 3, 2, 4, 1

E. 5, 3, 2, 4, 1

59. 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.

E. All of these statements are true.

43. Which of the following statements accurately describe events that occur as a result of a local potential reaching threshold? A. Activation gates of Na+ ion channels begin to close. B. Inactivation gates of Na+ ion channels begin to open. C. A positive feedback cycle develops in which depolarization causes activation gates of Na+ ion channels to open. D. K+ ion channels begin to close. E. Inactivation gates of Na+ ion channels begin to open and a positive feedback cycle develops in which depolarization causes activation gates of Na+ ion channels to open.

E. Inactivation gates of Na+ ion channels begin to open and a positive feedback cycle develops in which depolarization causes activation gates of Na+ ion channels to open.

51. Which of the following situations will lead to hyperpolarization? A. increase the permeability of the plasma membrane to Na+ ions B. decrease the permeability of the plasma membrane to K+ ions C. decrease the permeability of the plasma membrane to chloride ions D. any positive ion entering the cell E. None of these situations will lead to hyperpolarization.

E. None of these situations will lead to hyperpolarization.

42. A change in the resting membrane potential has the following characteristics (non-propagated, graded, can summate). This type of change can A. be a local potential. B. be an action potential. C. be a consequence of an increase in the permeability to Na+. D. result in repolarization. E. be a local potential and a consequence of an increase in the permeability to Na+.

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

48. Voltage-gated sodium channels are sensitive to changes in the extracellular concentration of A. potassium ions. B. proteins. C. sodium ions. D. chloride ions. E. calcium ions.

E. calcium ions.

91. An inhibitory postsynaptic potential (IPSP) can result from the influx of A. calcium ions. B. sodium ions. C. chloride. D. potassium ions. E. either chloride or potassium ions.

E. either influx of chloride or outflow of potassium ions.

127. Schwann cell ________________________________________

E. form myelin sheath around part of the axon in the PNS

84. A neuromodulator A. acts as a neurotransmitter. B. inactivates neurotransmitters. C. is a receptor site for a neurotransmitter. D. has no influence on the amount of neurotransmitter released. E. is a substance released from neurons that influences the sensitivity of neurons to neurotransmitters.

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

90. In an EPSP (excitatory postsynaptic potential), there is a A. net movement of sodium ions out of the cells. B. net movement of chloride ions into the cells. C. decrease in action potential amplitude. D. local hyperpolarization. E. local depolarization.

E. local depolarization.

120. postassium ions ________________________________________

E. plasma membrane is more permeable to this ion because of nongated ion channels

113. The figure is a process figure of the chemical synapse. What does "C" represent? A. postsynaptic membrane B. synaptic cleft C. synaptic vesicle D. voltage-gated calcium channel E. presynaptic terminal

E. presynaptic terminal

124. repolarization ________________________________________

E. return to the resting membrane potential

105. Identify structure "E" on the neuron. A. Schwann cell B. Node of Ranvier C. neuron cell body (soma) D. dendrites E. axon

Node of Ranvier

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

Peripheral

115. The figure is a process figure of the chemical synapse. What does "E" represent? A. postsynaptic membrane B. synaptic cleft C. synaptic vesicle D. voltage-gated calcium channel E. presynaptic terminal

Postsynaptic membrane