Nervous Tissue Chapter 12 Review
114) The minimum stimulus required to trigger an action potential is known as theA) threshold.B) all-or-none response.C) potential.D) incentive.E) summation.
Answer: ALearning Outcome: 12-5 Bloom's
57) Glial cells that surround the neurons in ganglia areA) astrocytes.B) satellite cells.C) oligodendrocytes.D) microglia.E) ependymal cells.
Answer: BLearning Outcome: 12-3 Bloom's
2) Which neuroglia myelinate CNS axons and which neuroglia myelinate PNS axons? (Figure 12-4) A) oligodendrocytes; Schwann cells B) Schwann cells; oligodendrocytes C) astrocytes; satellite cells D) satellite cells; astrocytes E) astrocytes; Schwann cells
Answer: A Learning Outcome: 12-3 Bloom's
10) ________ nerves are nerves that connect to the spinal cord.A) SpinalB) CranialC) AfferentD) MultipolarE) Autonomic
Answer: ALearning Outcome: 12-1 Bloom's
19) Axons terminate in a series of fine extensions known asA) telodendria.B) terminals.C) collaterals.D) dendrites.E) synapses.
Answer: ALearning Outcome: 12-2 Bloom's
22) Neurons that are rare, small, and lack features that distinguish dendrites from axons are calledA) anaxonic.B) unipolar.C) bipolar.D) tripolar.E) multipolar.
Answer: ALearning Outcome: 12-2 Bloom's
26) Sensory neurons of the PNS areA) unipolar.B) bipolar.C) anaxonic.D) multipolar.E) tripolar.
Answer: ALearning Outcome: 12-2 Bloom's
27) Which of the following activities or sensations is/are not monitored by interoceptors?A) sightB) painC) activities of the digestive systemD) cardiovascular activitiesE) urinary activities
Answer: ALearning Outcome: 12-2 Bloom's
31) The structure labeled "2" is a(n)A) neurofilament.B) dendrite.C) initial segment.D) perikaryon.E) axon.
Answer: ALearning Outcome: 12-2 Bloom's
38) ________ monitor the position of skeletal muscles and joints.A) ProprioceptorsB) InternoceptorsC) PhotoreceptorsD) ExteroceptorsE) Pressoreceptors
Answer: ALearning Outcome: 12-2 Bloom's
43) The basic functional unit of the nervous system is theA) neuron.B) axon.C) nerve.D) glial cell.E) receptor.
Answer: ALearning Outcome: 12-2 Bloom's
44) The most common neuron of the nervous system is theA) interneuron.B) externoceptor.C) bipolar neuron.D) unipolar neuron.E) microglial cell.
Answer: ALearning Outcome: 12-2 Bloom's
49) The largest and most numerous of the glial cells in the central nervous system are theA) astrocytes.B) satellite cells.C) oligodendrocytes.D) microglia.E) ependymal cells.
Answer: ALearning Outcome: 12-3 Bloom's
52) The neuroglial cells that participate in maintaining the blood-brain barrier are theA) astrocytes.B) ependymal cells.C) microglia.D) oligodendrocytes.E) Schwann cells.
Answer: ALearning Outcome: 12-3 Bloom's
70) Opening of sodium channels in the axon membrane causesA) depolarization.B) repolarization.C) hyperpolarization.D) increased negative charge inside the membrane.E) inhibition.
Answer: ALearning Outcome: 12-4 Bloom's
78) If the sodium-potassium pumps in the plasma membrane fail to function, all of the following occur exceptA) the intracellular concentration of potassium ions will increase.B) the neuron will slowly depolarize.C) the membrane will slowly lose its capacity to generate action potentials.D) the inside of the membrane will have a resting membrane potential that is more positive than normal.E) the intracellular concentration of sodium ions will increase.
Answer: ALearning Outcome: 12-4 Bloom's
83) Voltage-gated sodium channels have both an activation gate and a(n) ________ gate.A) inactivationB) ionC) swingingD) repolarizationE) threshold
Answer: ALearning Outcome: 12-4 Bloom's
85) A movement of charges in response to a potential difference is calledA) current.B) depolarization.C) hyperpolarization.D) action potential.E) electricity.
Answer: ALearning Outcome: 12-4 Bloom's
88) The equilibrium potential of potassium isA) -90mV.B) -65mV.C) -70mV.D) +30mV.E) +66mV.
Answer: ALearning Outcome: 12-4 Bloom's
102) Which area of the graph shows when voltage-gated sodium channels are open?A) 2B) 4C) 1D) 5E) 3
Answer: ALearning Outcome: 12-5 Bloom's
110) Which of the following types of nerve fiber possesses the fastest speed of impulse propagation?A) type AB) type BC) type CD) type DE) type E
Answer: ALearning Outcome: 12-5 Bloom's
112) Sensory information from skeletal muscles travels over ________ fibers.A) type AB) type BC) type CD) type DE) type E
Answer: ALearning Outcome: 12-5 Bloom's
113) In which of the following would the rate of impulse conduction be the greatest?A) a myelinated fiber of 10-µm diameterB) a nonmyelinated fiber of 20-µm diameterC) a myelinated fiber of 1-µm diameterD) a nonmyelinated fiber of 10-µm diameterE) It would be the same in all because of the all-or-none principle.
Answer: ALearning Outcome: 12-5 Bloom's
117) The period during which an excitable membrane can respond again, but only if the stimulus is greater than the threshold stimulus, is the ________ period.A) relative refractoryB) absolute refractoryC) restingD) lagE) stationary
Answer: ALearning Outcome: 12-5 Bloom's
92) Which of the following statements about the action potential is false?A) The rapid depolarization phase is caused by the entry of potassium ions.B) During the repolarization phase, sodium channels close and potassium channels open.C) During the depolarization phase, membrane potential becomes positive.D) During the hyperpolarization phase, the ion pumps re-establish the sodium and potassium concentrations across the cell membrane.E) Repolarization occurs as potassium ions leave the axon.
Answer: ALearning Outcome: 12-5 Bloom's
93) How would the absolute refractory period be affected if voltage-regulated sodium channels failed to inactivate?A) It would last indefinitely.B) It would be much briefer.C) It would be basically unaffected.
Answer: ALearning Outcome: 12-5 Bloom's
96) A threshold stimulus is theA) depolarization necessary to cause an action potential.B) peak of an action potential.C) hyperpolarization of an axon.D) resting membrane potential.E) electrical current that crosses the synaptic cleft.
Answer: ALearning Outcome: 12-5 Bloom's
97) Which of the following is true about threshold for an action potential?A) It is more positive than the resting membrane potential.B) Voltage-gated potassium channels begin to close.C) Voltage-gated potassium channels begin to open.D) The membrane begins to hyperpolarize.E) Threshold for a typical neuron is approximately -30 mV.
Answer: ALearning Outcome: 12-5 Bloom's
121) Which type of synapse is most common in the nervous system?A) chemicalB) electricalC) mechanicalD) processingE) radiative
Answer: ALearning Outcome: 12-6 Bloom's
125) If the chemically gated sodium channels in the postsynaptic membrane were completely blocked,A) synaptic transmission would fail.B) release of neurotransmitter would stop.C) smaller action potentials would result.D) the presynaptic membrane would be unable to reach threshold.E) the presynaptic neuron would release a different neurotransmitter.
Answer: ALearning Outcome: 12-6 Bloom's
127) When cholinergic receptors are stimulated,A) sodium ions enter the postsynaptic neuron.B) sodium ions leave the postsynaptic neuron.C) chloride ions enter the postsynaptic neuron.D) chloride ions leave the postsynaptic neuron.E) norepinephrine deactivates acetylcholine.
Answer: ALearning Outcome: 12-6 Bloom's
130) In a(n) ________ synapse, current flows directly between cells.A) electricalB) cellC) chemicalD) osmoticE) gap
Answer: ALearning Outcome: 12-6 Bloom's
134) Which of the following is the most important excitatory neurotransmitter in the brain that is important in learning and memory?A) glutamateB) gamma aminobutyric acidC) serotoninD) noradrenalineE) glycine
Answer: ALearning Outcome: 12-7 Bloom's
136) A deficiency in which neurotransmitter would cause Parkinson's-like symptoms?A) dopamineB) norepinephrineC) serotoninD) GABAE) endorphins
Answer: ALearning Outcome: 12-7 Bloom's
141) The molecule responsible for making cyclic AMP is calledA) adenylate cyclase.B) adenosine.C) anandamide.D) adenosine synthase.E) G-protein.
Answer: ALearning Outcome: 12-7 Bloom's
148) Summation that results from the cumulative effect of multiple synapses at multiple places on the neuron is designatedA) spatial summation.B) temporal summation.C) inhibition of the impulse.D) hyperpolarization.E) impulse transmission.
Answer: ALearning Outcome: 12-8 Bloom's
152) The release of GABA and subsequent inhibition of voltage gated calcium channels is associated withA) presynaptic inhibition.B) presynaptic facilitation.C) spatial summation.D) temporal summation.E) spatial facilitation.
Answer: ALearning Outcome: 12-8 Bloom's
3) The part of the peripheral nervous system that carries sensory information to the CNS is designatedA) motor.B) afferent.C) efferent.D) autonomic.E) somatic.
Answer: BLearning Outcome: 12-1 Bloom's
5) The nervous tissue outside of the central nervous system composes the ________ nervous system.A) somaticB) peripheralC) autonomicD) afferentE) parasympathetic
Answer: BLearning Outcome: 12-1 Bloom's
9) ________ carry motor information to peripheral effectors.A) Unipolar neuronsB) Efferent neuronsC) Multipolar neuronsD) Afferent neuronsE) Interneurons
Answer: BLearning Outcome: 12-1 Bloom's
21) The rabies virus travels to the CNS viaA) anterograde axoplasmic transport.B) retrograde axoplasmic transport.C) blood vessels.D) subcutaneous connective tissue.E) cerebrospinal fluid.
Answer: BLearning Outcome: 12-2 Bloom's
23) Neurons in which dendritic and axonal processes are continuous and the soma lies off to one side are calledA) anaxonic.B) unipolar.C) bipolar.D) tripolar.E) multipolar.
Answer: BLearning Outcome: 12-2 Bloom's
33) Identify the structure labeled "4."A) synaptic terminalsB) telodendriaC) dendritic spinesD) collateral branchesE) axons
Answer: BLearning Outcome: 12-2 Bloom's
37) On which structure do most neuron to neuron communications occur?A) 2B) 1C) 3D) 4E) 5
Answer: BLearning Outcome: 12-2 Bloom's
47) Which of the following is not a function of the neuroglia?A) supportB) memoryC) secretion of cerebrospinal fluidD) maintenance of blood-brain barrierE) phagocytosis
Answer: BLearning Outcome: 12-3 Bloom's
48) Which of the following is a type of glial cell found in the peripheral nervous system?A) astrocytesB) satellite cellsC) oligodendrocytesD) microgliaE) ependymal cells
Answer: BLearning Outcome: 12-3 Bloom's
50) Functions of astrocytes include all of the following exceptA) maintaining the blood-brain barrier.B) conducting action potentials.C) guiding neuron development.D) responding to neural tissue damage.E) forming a three-dimensional framework for the CNS.
Answer: BLearning Outcome: 12-3 Bloom's
58) Damage to ependymal cells would most likely affect theA) formation of myelin sheaths.B) formation of cerebrospinal fluid.C) formation of ganglia.D) repair of axons.E) transport of neurotransmitters within axons.
Answer: BLearning Outcome: 12-3 Bloom's
61) The tiny gaps between adjacent Schwann cells are calledA) neurillema.B) nodes of Ranvier.C) axolemma.D) terminals.E) vesicles.
Answer: BLearning Outcome: 12-3 Bloom's
62) Regions of the CNS with an abundance of myelinated axons constitute the ________ matter.A) grayB) whiteC) neuralD) brainE) ganglion
Answer: BLearning Outcome: 12-3 Bloom's
63) Regions of the CNS where neuron cell bodies dominate constitute the ________ matter.A) whiteB) grayC) neuralD) brainE) ganglion
Answer: BLearning Outcome: 12-3 Bloom's
67) Which of the following is not true regarding the establishment of a neuron's resting membrane potential?A) Chemical and electrical forces both favor sodium ions entering the cell.B) Electrical forces do not push sodium ions into the cell.C) The chemical gradient for potassium ions tends to drive them out of the cell.D) Ion pumps in the plasma membrane eject sodium ions as fast as they cross the membrane.E) Resting membrane permeability to Na+ is very low.
Answer: BLearning Outcome: 12-4 Bloom's
80) When potassium channels open and the ions diffuse through the membrane,A) the inside of the membrane will become more positive.B) the inside of the membrane will become more negative.C) there will be almost no effect on transmembrane potential.D) the membrane will become depolarized.E) the membrane will depolarize to threshold.
Answer: BLearning Outcome: 12-4 Bloom's
87) A shift of the resting transmembrane potential toward 0 mV is calledA) potential difference.B) depolarization.C) hyperpolarization.D) polarization.E) repolarization.
Answer: BLearning Outcome: 12-4 Bloom's
101) Which area of the graph shows when chemically gated sodium channels are open?A) 3B) 1C) 2D) 5E) 4
Answer: BLearning Outcome: 12-5 Bloom's
104) In which area of the graph do you see a sudden rush of sodium ions into the neuron?A) 1B) 2C) 3D) 4
Answer: BLearning Outcome: 12-5 Bloom's
108) Rapid impulse conduction from "node" to "node" is calledA) spatial propagation.B) saltatory propagation.C) divergent propagation.D) synaptic transmission.E) continuous propagation.
Answer: BLearning Outcome: 12-5 Bloom's
115) The ________ principle states that the size and speed of the action potential are independent of the stimulus strength.A) thresholdB) all-or-noneC) summationD) polarizationE) potential
Answer: BLearning Outcome: 12-5 Bloom's
116) The period during which an excitable membrane cannot respond to further stimulation is the ________ period.A) relative refractoryB) absolute refractoryC) restingD) lagE) stationary
Answer: BLearning Outcome: 12-5 Bloom's
90) The following are the main steps in the generation of an action potential.1. Sodium channels are inactivated.2. Voltage-gated potassium channels open and potassium moves out of the cell, initiating repolarization.3. Sodium channels regain their normal properties.4. A graded depolarization brings an area of an excitable membrane to threshold.5. A temporary hyperpolarization occurs.6. Sodium channel activation occurs.7. Sodium ions enter the cell and depolarization occurs.What is the proper sequence of these events?A) 4, 6, 7, 3, 2, 5, 1B) 4, 6, 7, 1, 2, 3, 5C) 6, 7, 4, 1, 2, 3, 5D) 2, 4, 6, 7, 1, 3, 5E) 4, 2, 5, 6, 7, 3, 1
Answer: BLearning Outcome: 12-5 Bloom's
91) The all-or-none principle states thatA) all stimuli will produce identical action potentials.B) all stimuli great enough to bring the membrane to threshold will produce identical action potentials.C) the greater the magnitude of the stimuli, the greater the magnitude of the action potential.D) only sensory stimuli can activate action potentials.E) only motor stimuli can activate action potentials.
Answer: BLearning Outcome: 12-5 Bloom's
94) During repolarization of a neuronA) sodium ions move out of the cell.B) potassium ions move out of the cell.C) potassium ions move into the cell.D) both sodium and potassium ions move into the cell.E) sodium ions move into the cell.
Answer: BLearning Outcome: 12-5 Bloom's
124) The following are the steps involved in transmission at a cholinergic synapse. What is the correct sequence for these events?1. Chemically-gated sodium channels on the postsynaptic membrane are activated.2. Calcium ions enter the synaptic terminal.3. Acetylcholinesterase hydrolyzes acetylcholine.4. An action potential depolarizes the synaptic terminal at the presynaptic membrane.5. The pre-synaptic terminal reabsorbs choline.6. Acetylcholine is released from storage vesicles by exocytosis.7. Acetylcholine binds to receptors on the postsynaptic membrane.8. Calcium ions are removed from the cytoplasm of the pre- synaptic terminal.A) 4, 2, 6, 7, 8, 5, 3, 1B) 4, 2, 6, 7, 1, 8, 3, 5C) 2, 4, 6, 7, 1, 8, 3, 5D) 2, 5, 4, 6, 7, 1, 8, 3E) 6, 4, 2, 7, 1, 8, 3, 5
Answer: BLearning Outcome: 12-6 Bloom's
131) At a synapse the 0.2-0.5 milliseconds it takes for calcium influx and neurotransmitter release is calledA) latency period.B) synaptic delay.C) recovery period.D) repolarization.E) synaptic diffusion.
Answer: BLearning Outcome: 12-6 Bloom's
3) Which part of an acetylcholine (ACh) molecule undergoes reuptake by the axon terminal to be reused in another acetylcholine molecule? (Figure 12-16)A) acetateB) cholineC) coenzyme AD) calciumE) acetyl-CoA
Answer: BLearning Outcome: 12-6 Bloom's
133) Adrenergic synapses release the neurotransmitterA) acetylcholine.B) norepinephrine.C) dopamine.D) serotonin.E) GABA.
Answer: BLearning Outcome: 12-7 Bloom's
146) IPSPs (inhibitory postsynaptic potentials)A) are local depolarizations.B) are local hyperpolarizations.C) increase membrane permeability to sodium ions.D) block the efflux of potassium ions.E) block the efflux of calcium ions.
Answer: BLearning Outcome: 12-8 Bloom's
147) When a second EPSP (excitatory postsynaptic potential) arrives at a single synapse before the effects of the first have disappeared, what occurs?A) spatial summationB) temporal summationC) inhibition of the impulseD) hyperpolarizationE) decrease in speed of impulse transmission
Answer: BLearning Outcome: 12-8 Bloom's
150) In ________, activity at an axoaxonic synapse increases the amount of neurotransmitter released when an action potential arrives at the axon terminus.A) presynaptic inhibitionB) presynaptic facilitationC) spatial summationD) temporal summationE) spatial facilitation
Answer: BLearning Outcome: 12-8 Bloom's
151) In one form of presynaptic inhibition the release of ________ inhibits the opening of voltage gated calcium channels in the axon terminus.A) glutamateB) GABAC) serotoninD) dopamineE) aspartate
Answer: BLearning Outcome: 12-8 Bloom's
1) The ________ nervous system is composed of the brain and spinal cord.A) autonomicB) peripheralC) centralD) efferentE) afferent
Answer: CLearning Outcome: 12-1 Bloom's
8) The ________ nervous system provides involuntary regulation of smooth muscle, cardiac muscle, and glandular activity.A) somaticB) peripheralC) autonomicD) afferentE) motor
Answer: CLearning Outcome: 12-1 Bloom's
14) The most abundant class of neuron in the central nervous system isA) anaxonic.B) bipolar.C) multipolar.D) pseudopolar.E) unipolar.
Answer: CLearning Outcome: 12-2 Bloom's
18) Branches that may occur along an axon are calledA) telodendria.B) synaptic terminals.C) collaterals.D) hillocks.E) synapses.
Answer: CLearning Outcome: 12-2 Bloom's
24) Neurons that have one axon and one dendrite, with the soma in between, are calledA) anaxonic.B) unipolar.C) bipolar.D) tripolar.E) multipolar.
Answer: CLearning Outcome: 12-2 Bloom's
30) The structures labeled "1" are dendrites. Their membranes contain numerous chemically-gated ion channels.A) The first statement is true but the second statement is false.B) The first statement is false but the second statement is true.C) Both statements are true.D) Both statements are false.
Answer: CLearning Outcome: 12-2 Bloom's
41) ________ monitor the digestive, respiratory, cardiovascular, urinary, and reproductive systems.A) Spinal nervesB) Unipolar neuronsC) InternoceptorsD) ExteroceptorsE) Proprioceptors
Answer: CLearning Outcome: 12-2 Bloom's
51) ________ account for roughly half of the volume of the nervous system.A) AxonsB) DendritesC) NeurogliaD) SynapsesE) Efferent fibers
Answer: CLearning Outcome: 12-3 Bloom's
53) The myelin sheath that covers many CNS axons is formed byA) astrocytes.B) satellite cells.C) oligodendrocytes.D) microglia.E) ependymal cells.
Answer: CLearning Outcome: 12-3 Bloom's
60) In the peripheral nervous system, Schwann cells participate in the repair of damaged nerves byA) producing new axons.B) regenerating cell bodies for the neurons.C) forming a cellular cord that directs axonal regrowth.D) clearing away cellular debris.E) producing more satellite cells that fuse to form new axons.
Answer: CLearning Outcome: 12-3 Bloom's
69) Ion channels that are always open are called ________ channels.A) activeB) gatedC) leakD) regulatedE) local
Answer: CLearning Outcome: 12-4 Bloom's
71) Voltage-gated channels are presentA) at the motor end plate.B) on the surface of dendrites.C) in the membrane that covers axons.D) on the soma of neurons.E) along the perikaryon of neurons.
Answer: CLearning Outcome: 12-4 Bloom's
73) ________ open or close in response to binding specific molecules.A) Leak channelsB) Activated channelsC) Chemically gated channelsD) Voltage-gated channelsE) Voltage-gated and chemically gated channels
Answer: CLearning Outcome: 12-4 Bloom's
77) Which of the following is not involved in creating the resting membrane potential of a neuron?A) diffusion of potassium ions out of the cellB) diffusion of sodium ions into the cellC) membrane permeability for sodium ions greater than potassium ionsD) membrane permeability for potassium ions greater than sodium ionsE) The interior of the plasma membrane has an excess of negative charges.
Answer: CLearning Outcome: 12-4 Bloom's
79) Graded potentialsA) produce an effect that increases with distance from the point of stimulation.B) produce an effect that spreads actively across the membrane surface.C) may be either a depolarization or a hyperpolarization.D) are often all-or-none.E) cause repolarization.
Answer: CLearning Outcome: 12-4 Bloom's
86) The sum of the electrical and chemical forces acting on an ion is known as itsA) permeability gradient.B) thermodynamic difference.C) electrochemical gradient.D) action potential.E) summation difference.
Answer: CLearning Outcome: 12-4 Bloom's
103) Which area of the graph shows when potassium channels open?A) 1B) 2C) 3D) 4
Answer: CLearning Outcome: 12-5 Bloom's
106) Which point of the graph shows when potassium ion outflow exceeds sodium ion inflow?A) 1B) 2C) 3D) 4
Answer: CLearning Outcome: 12-5 Bloom's
111) Type ________ fibers have the largest diameter axons.A) SB) FC) AD) BE) C
Answer: CLearning Outcome: 12-5 Bloom's
119) Below are the events that occur during continuous propagation of action potential. Select the correct order in which the events occur.1. Adjacent membrane segment depolarizes.2. Local current spreads to adjacent voltage gated channel.3. Threshold is met.4. Local current develops due to sodium moving in the cytosol.A) 2,4,3,1B) 2,4,1,3C) 4,2,3,1D) 4,2,1,3E) 1,4,2,3
Answer: CLearning Outcome: 12-5 Bloom's
99) What is occurring at the area labeled #4?A) An inhibitory stimulus has occurred.B) Chemically gated potassium channels have opened.C) Excessive potassium has diffused out causing hyperpolarization.D) Sodium ions have been pumped out of the neuron.E) Excessive depolarization of the axon has occurred.
Answer: CLearning Outcome: 12-5 Bloom's
122) The ion that triggers the release of acetylcholine into the synaptic cleft isA) sodium.B) potassium.C) calcium.D) chloride.E) magnesium.
Answer: CLearning Outcome: 12-6 Bloom's
129) At a(n) ________ synapse, a neurotransmitter is released to stimulate the postsynaptic membrane.A) electricalB) cellC) chemicalD) osmoticE) gap
Answer: CLearning Outcome: 12-6 Bloom's
132) Synaptic delay is caused byA) neurotransmitter diffusion.B) binding of acetylcholine to post-synaptic receptors.C) calcium influx and neurotransmitter release.D) production and transport of neurotransmitter within the neuron.E) the lack of permeability of the post-synaptic membrane.
Answer: CLearning Outcome: 12-6 Bloom's
135) After acetylcholinesterase acts, the synaptic terminalA) reabsorbs the acetylcholine.B) reabsorbs the acetate.C) reabsorbs the choline.D) reabsorbs axoplasm.E) pinches off and a new terminal grows.
Answer: CLearning Outcome: 12-7 Bloom's
138) Which neurotransmitter has widespread effects on a person's attention and emotional state?A) dopamineB) norepinephrineC) serotoninD) GABAE) endorphins
Answer: CLearning Outcome: 12-7 Bloom's
142) Which of the following is the primary second messenger in G-protein coupled post-synaptic cells?A) NOB) COC) cAMPD) GABAE) ATP
Answer: CLearning Outcome: 12-7 Bloom's
143) A postsynaptic neuron will have an excitatory postsynaptic potential (EPSP) whenA) chemically regulated potassium channels are open and potassium is diffusing out of the cell.B) more calcium ions than usual diffuse into the neuron.C) chemically regulated sodium channels are open and sodium is diffusing into the cell.D) the neuron is hyperpolarized.E) more potassium ions than usual diffuse out of the neuron.
Answer: CLearning Outcome: 12-8 Bloom's
144) The site in the neuron where EPSPs and IPSPs are integrated is theA) chemical synapse.B) electrical synapse.C) axon hillock.D) dendritic membrane.E) synaptic terminal.
Answer: CLearning Outcome: 12-8 Bloom's
149) A neuron whose membrane potential shifts closer to threshold is said to beA) hyperpolarized.B) depolarized.C) facilitated.D) repolarized.E) at equilibrium.
Answer: CLearning Outcome: 12-8 Bloom's
1) The axon hillock is a region between what two general regions of a neuron? (Figure 12-2) A) dendrites and cell body B) nucleolus and nucleus C) axon and axon terminals D) cell body and axon E) dendrites and telodendria
Answer: D Learning Outcome: 12-2 Bloom's
11) ________ nerves are nerves that connect to the brain.A) SpinalB) UnmyelinatedC) MyelinatedD) CranialE) Interneural
Answer: DLearning Outcome: 12-1 Bloom's
2) The ________ nervous system controls the skeletal muscles.A) sympatheticB) parasympatheticC) afferentD) somaticE) autonomic
Answer: DLearning Outcome: 12-1 Bloom's
6) The ________ division of the peripheral nervous system brings sensory information to the central nervous system.A) somaticB) peripheralC) autonomicD) afferentE) parasympathetic
Answer: DLearning Outcome: 12-1 Bloom's
13) Which of the following is not a recognized structural classification for neurons?A) anaxonicB) bipolarC) multipolarD) pseudopolarE) unipolar
Answer: DLearning Outcome: 12-2 Bloom's
16) Clusters of RER and free ribosomes in neurons are calledA) neurofilaments.B) neurofibrils.C) perikaryon.D) Nissl bodies.E) microglia.
Answer: DLearning Outcome: 12-2 Bloom's
17) The axon is connected to the soma at theA) telodendria.B) synaptic terminal.C) collaterals.D) axon hillock.E) synapse.
Answer: DLearning Outcome: 12-2 Bloom's
29) How does blocking retrograde axoplasmic transport in an axon affect the activity of a neuron?A) The neuron becomes unable to produce neurotransmitters.B) The neuron becomes unable to produce action potentials.C) The soma becomes unable to export products to the synaptic terminals.D) The soma becomes unable to respond to changes in the distal end of the axon.E) The neuron becomes unable to depolarize when stimulated.
Answer: DLearning Outcome: 12-2 Bloom's
34) Identify the structure labeled "5."A) axonsB) telodendriaC) dendritic spinesD) synaptic terminalsE) collateral branch
Answer: DLearning Outcome: 12-2 Bloom's
36) Which part(s) of the neuron can propagate an action potential?A) 1B) 1 and 2C) 2 and 3D) 3
Answer: DLearning Outcome: 12-2 Bloom's
39) ________ carry sensory information to the CNS.A) Motor neuronsB) Efferent neuronsC) Multipolar neuronsD) Afferent neuronsE) Interneurons
Answer: DLearning Outcome: 12-2 Bloom's
40) ________ provide information about the external environment.A) Spinal nervesB) Anaxonic neuronsC) InternoceptorsD) ExteroceptorsE) Proprioceptors
Answer: DLearning Outcome: 12-2 Bloom's
45) Most neurons lack ________ and so are permanently blocked from undergoing cell division.A) ribosomesB) endoplasmic reticulaC) a nucleusD) centriolesE) cytoplasm
Answer: DLearning Outcome: 12-2 Bloom's
46) Deteriorating changes in the distal segment of an axon as a result of a break between it and the soma is called ________ degeneration.A) neuralB) centralC) peripheralD) WallerianE) conduction
Answer: DLearning Outcome: 12-3 Bloom's
55) Small, wandering cells that engulf cell debris and pathogens in the CNS are calledA) astrocytes.B) satellite cells.C) oligodendrocytes.D) microglia.E) ependymal cells.
Answer: DLearning Outcome: 12-3 Bloom's
64) Which of the following is not a function of astrocytes?A) They create a three dimensional framework for the CNS.B) They maintain the blood-brain barrier.C) They guide neuron development.D) They rebuild injured neurons.E) They adjust the composition of the interstitial tissue.
Answer: DLearning Outcome: 12-3 Bloom's
65) All of the following cause demyelination exceptA) heavy-metal ion poisoning.B) diphtheria.C) multiple sclerosis.D) dopamine deficiency.E) All of these cause demyelination.
Answer: DLearning Outcome: 12-3 Bloom's
68) At the normal resting membrane potential of a typical neuron, its sodium-potassium exchange pump transportsA) 1 intracellular sodium ion for 2 extracellular potassium ions.B) 2 intracellular sodium ions for 1 extracellular potassium ion.C) 3 intracellular sodium ions for 1 extracellular potassium ion.D) 3 intracellular sodium ions for 2 extracellular potassium ions.E) 3 extracellular sodium ions for 2 intracellular potassium ions.
Answer: DLearning Outcome: 12-4 Bloom's
72) The sodium-potassium ion exchange pumpA) must reestablish ion concentrations after each action potential.B) transports sodium ions into the cell during depolarization.C) transports potassium ions out of the cell during repolarization.D) moves sodium and potassium opposite to the direction of their electrochemical gradients.E) depends on a hydrogen gradient for energy.
Answer: DLearning Outcome: 12-4 Bloom's
74) ________ channels open or close in response to physical distortion of the membrane surface.A) Voltage-gatedB) Chemically gatedC) ActiveD) Mechanically gatedE) Leak
Answer: DLearning Outcome: 12-4 Bloom's
84) If acetylcholine (ACh) causes inhibition of a postsynaptic neuron, to what type of membrane channel did the ACh bind?A) mechanically-regulated channelB) voltage-regulated sodium channelC) voltage-regulated calcium channelD) chemically-regulated potassium channelE) chemically-regulated sodium channel
Answer: DLearning Outcome: 12-4 Bloom's
100) What is occurring in the area between #2 and #3?A) An excitatory graded potential is occurring.B) Potassium ions are entering the axon and causing depolarization.C) Chemically gated sodium channels are open and sodium is diffusing into the axon.D) Sodium ions are entering the axon and causing depolarization.E) Repolarization of the axon due to sodium ions leaving the axon is occurring.
Answer: DLearning Outcome: 12-5 Bloom's
105) Which area of the graph shows when membrane potential approaches the potassium equilibrium potential?A) 1B) 2C) 3D) 4
Answer: DLearning Outcome: 12-5 Bloom's
107) When is the neuron in the relative refractory period?A) 1B) 2C) 3D) 4
Answer: DLearning Outcome: 12-5 Bloom's
98) Puffer fish poison blocks voltage-gated sodium channels like a cork. What effect would this neurotoxin have on the function of neurons?A) Neurons would depolarize more rapidly.B) Action potentials would lack a repolarization phase.C) The absolute refractory period would be shorter than normal.D) The axon would be unable to generate action potentials.E) None, because the chemically gated sodium channels would still function.
Answer: DLearning Outcome: 12-5 Bloom's
123) Cholinergic synapses release the neurotransmitterA) norepinephrine.B) adrenalin.C) serotonin.D) acetylcholine.E) GABA.
Answer: DLearning Outcome: 12-6 Bloom's
137) Which neurotransmitter has a direct effect on opening chloride channels?A) dopamineB) norepinephrineC) serotoninD) GABAE) endorphins
Answer: DLearning Outcome: 12-7 Bloom's
139) Which of the following neurotransmitters is a dissolved gas?A) serotoninB) glutamateC) aspartateD) nitric oxideE) histamine
Answer: DLearning Outcome: 12-7 Bloom's
145) EPSPs (excitatory postsynaptic potentials) occur whenA) more potassium ions than usual leak out of a cell.B) more calcium ions than usual leak out of a cell.C) chloride ions enter a cell.D) extra sodium ions enter a cell.E) hyperpolarizations occur.
Answer: DLearning Outcome: 12-8 Bloom's
4) The efferent division of the peripheral nervous system innervates ________ cells.A) skeletal muscleB) smooth muscleC) heart muscleD) glandularE) All of the answers are correct.
Answer: ELearning Outcome: 12-1 Bloom's
7) The ________ division of the nervous system carries motor commands to muscles and glands.A) spinalB) peripheralC) autonomicD) afferentE) efferent
Answer: ELearning Outcome: 12-1 Bloom's
12) The axoplasm of the axon contains which of the following?A) neurotubulesB) mitochondriaC) vesiclesD) neurofibrilsE) All of the answers are correct.
Answer: ELearning Outcome: 12-2 Bloom's
15) The cytoplasm that surrounds the nucleus of a neuron is called theA) protoplasm.B) nucleoplasm.C) sarcoplasm.D) neuroplasm.E) perikaryon.
Answer: ELearning Outcome: 12-2 Bloom's
20) The site of intercellular communication between a neuron and another cell is theA) telodendria.B) axolemma.C) collateral.D) hillock.E) synapse.
Answer: ELearning Outcome: 12-2 Bloom's
25) Neurons that have several dendrites and a single axon are calledA) anaxonic.B) unipolar.C) bipolar.D) tripolar.E) multipolar.
Answer: ELearning Outcome: 12-2 Bloom's
28) ________ are the most numerous type of neuron in the CNS.A) Sensory neuronsB) Motor neuronsC) Unipolar neuronsD) Bipolar neuronsE) Interneurons
Answer: ELearning Outcome: 12-2 Bloom's
32) Which type of membrane channels are found at label "3"?A) voltage-gated Na+ channelsB) voltage-gated K+ channelsC) chemically-gated Na+ and K+ channelsD) voltage-gated Ca2+ channelsE) both voltage-gated Na+ channels and voltage-gated K+ channels
Answer: ELearning Outcome: 12-2 Bloom's
35) What is contained inside the structure labeled "5"?A) neurogliaB) sodium ionsC) acetylcholinesteraseD) calcium ionsE) neurotransmitter molecules
Answer: ELearning Outcome: 12-2 Bloom's
42) The plasma membrane of an axon is called theA) axon terminal.B) neurilemma.C) myelin sheath.D) sarcolemma.E) axolemma.
Answer: ELearning Outcome: 12-2 Bloom's
54) ________ line the brain ventricles and spinal canal.A) AstrocytesB) Satellite cellsC) OligodendrocytesD) MicrogliaE) Ependymal cells
Answer: ELearning Outcome: 12-3 Bloom's
56) The neurilemma of axons in the peripheral nervous system is formed byA) astrocytes.B) satellite cells.C) oligodendrocytes.D) microglia.E) Schwann cells.
Answer: ELearning Outcome: 12-3 Bloom's
59) When pressure is applied to neural tissue, all of the following effects are possible exceptA) a decrease in blood flow.B) a decrease in available oxygen.C) a change in neuron excitability.D) glial cells degenerate.E) neurons are triggered to divide.
Answer: ELearning Outcome: 12-3 Bloom's
66) Which of the following can cause demyelination?A) arsenic poisoningB) diphtheriaC) multiple sclerosisD) mercury exposureE) Demyelination can be caused by arsenic, diphtheria, multiple sclerosis and mercury.
Answer: ELearning Outcome: 12-3 Bloom's
75) Any stimulus that opens a ________ ion channel will produce a graded potential.A) voltage-gatedB) chemically gatedC) sodiumD) mechanically gatedE) All of the answers are correct.
Answer: ELearning Outcome: 12-4 Bloom's
76) If the permeability of a resting axon to sodium ion increases,A) the membrane potential will repolarize.B) the membrane potential will hyperpolarize.C) inward movement of sodium ion will increase.D) outward movement of sodium ion will decrease.E) inward movement of sodium will increase and the membrane will depolarize.
Answer: ELearning Outcome: 12-4 Bloom's
81) Ions can move across the plasma membrane in which of the following ways?A) through voltage-gated channels as in the action potentialB) through passive or leak channelsC) by ATP-dependent ion pumps like the sodium-potassium exchange pumpD) through chemically gated channels as in neuromuscular transmissionE) All of the answers are correct.
Answer: ELearning Outcome: 12-4 Bloom's
82) Raising the potassium ion concentration in the extracellular fluid surrounding a nerve cell will have what effect?A) depolarize itB) hyperpolarize itC) increase the magnitude of the potassium equilibrium potentialD) decrease the magnitude of the potassium equilibrium potentialE) both hyperpolarize it and decrease the magnitude of the potassium equilibrium potential
Answer: ELearning Outcome: 12-4 Bloom's
89) The equilibrium potential of sodium isA) -90mV.B) -65mV.C) -70mV.D) +30mV.E) +66mV.
Answer: ELearning Outcome: 12-4 Bloom's
109) Which of the following does not influence the time necessary for a nerve impulse to be transmitted?A) length of the axonB) presence or absence of a myelin sheathC) diameter of the axonD) presence or absence of nodesE) whether or not the impulse begins in the CNS
Answer: ELearning Outcome: 12-5 Bloom's
118) The presence of ________ dramatically increases the speed at which an action potential moves along an axon.A) a capsuleB) plasma proteinC) neurilemmaD) glial cellsE) myelin
Answer: ELearning Outcome: 12-5 Bloom's
95) How would a chemical that prevents the opening of voltage-regulated Na+ channels affect the function of a neuron?A) The neuron will only be able to hyperpolarize.B) The neuron will depolarize more rapidly.C) Action potentials will lack a repolarization phase.D) The neuron will automatically and repeatedly produce graded potentials.E) The neuron will only be capable of producing graded potentials.
Answer: ELearning Outcome: 12-5 Bloom's
120) A neuron that receives neurotransmitter from another neuron is calledA) the presynaptic neuron.B) the motor neuron.C) an oligodendrocyte.D) a satellite cell.E) the postsynaptic neuron.
Answer: ELearning Outcome: 12-6 Bloom's
126) The effect that a neurotransmitter has on the postsynaptic membrane depends on theA) frequency of neurotransmitter release.B) nature of the neurotransmitter.C) characteristics of the receptors.D) quantity of neurotransmitters released.E) All of the answers are correct.
Answer: ELearning Outcome: 12-6 Bloom's
128) What triggers the release of acetylcholine from a synaptic terminal?A) release of calcium ions from the synaptic vesiclesB) graded potentials in the synaptic terminalC) synaptic vesicles fuse to dendritesD) diffusion of sodium ions out of the synaptic terminalE) diffusion of calcium ions into the synaptic terminal
Answer: ELearning Outcome: 12-6 Bloom's
140) Which of the following neurotransmitters are known to bind to G-protein coupled receptors?A) epinephrineB) serotoninC) dopamineD) GABAE) All of these bind to G-protein coupled receptors.
Answer: ELearning Outcome: 12-7 Bloom's
3) A drug that blocks ATP production is introduced into an isolated axon preparation. The axon is then repeatedly stimulated, and recordings are made of the response. What effects would you expect to observe?
Answer: Initially, the recording would show normal action potentials in response to the repetitive stimulation. After 50,000 to 100,000 action potentials have passed, the recording would start to indicate less responsiveness from the axon; ultimately, the axon would fail to respond. Because very few ions actually move across the membrane during an action potential, axons can carry thousands of action potentials before the concentrations of sodium and potassium ions must be reestablished by the sodium-potassium pump. Without ATP production, the supply of ATP would be consumed, the pump would shut down, and so the cell could not restore the sodium and potassium ion gradients. The resulting slow depolarization would inactivate voltage-gated sodium channels, leading to a persistent absolute refractory state. The loss of the electrochemical gradients denies the axons their means of generating an action potential and transmission would stop. Learning Outcome: 12-6 Bloom's
1) Rabies is caused by a virus that attacks the central nervous system. The virus is normally introduced by an animal bite that breaks the surface of the skin. Since the virus is not motile, how does it travel to the central nervous system?
Answer: When the skin is broken by an animal bite some cutaneous receptors are physically damaged. It is through these damaged axons that the virus gains entrance to the neuron. Retrograde axoplasmic transport carries the virus to the central nervous system, where it can reproduce and spread.Learning Outcome: 12-2 Bloom's
2) The myelination of central and peripheral axons occurs rapidly through the first few years of life. How can this developmental process explain the improved motor abilities of infants and toddlers?
Answer: Without full myelination, information about limb movement and body position moves slowly to the CNS, and motor commands move slowly and erratically to the muscles. By the time the brain is aware of movement or position and can issue a motor command, the limb has already moved. When the motor command reaches the skeletal muscle, the response is no longer appropriate. As the neurons become fully myelinated, information processing speeds up, so we observe improved balance, coordination, and movement.Learning Outcome: 12-3 Bloom's