Chapter 12 part 2 Anatomy Book Questions
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 acid C) serotoninD) noradrenalineE) glycine
A
136) A deficiency in which neurotransmitter would cause Parkinson's-like symptoms? A) dopamineB) norepinephrineC) serotonin D) GABAE) endorphins
A
141) The molecule responsible for making cyclic AMP is called A) adenylate cyclase.B) adenosine.C) anandamide. D) adenosine synthase.E) G-protein.
A
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.
A
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.
A
70) Opening of sodium channels in the axon membrane causes A) depolarization.B) repolarization.C) hyperpolarization. D) increased negative charge inside the membrane. E) inhibition.
A
130) In a(n) ________ synapse, current flows directly between cells. A) electricalB) cellC) chemical D) osmoticE) gap
A
122) The ion that triggers the release of acetylcholine into the synaptic cleft is A) sodium.B) potassium.C) calcium. D) chloride.E) magnesium.
C
129) At a(n) ________ synapse, a neurotransmitter is released to stimulate the postsynaptic membrane.A) electricalB) cell C) chemicalD) osmoticE) gap
C
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.
C
135) After acetylcholinesterase acts, the synaptic terminal A) reabsorbs the acetylcholine.B) reabsorbs the acetate.C) reabsorbs the choline. D) reabsorbs axoplasm.E) pinches off and a new terminal grows.
C
138) Which neurotransmitter has widespread effects on a person's attention and emotional state? A) dopamineB) norepinephrineC) serotonin D) GABAE) endorphins
C
142) Which of the following is the primary second messenger in G-protein coupled post-synaptic cells?A) NOB) CO C) cAMPD) GABAE) ATP
C
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.
C
144) The site in the neuron where EPSPs and IPSPs are integrated is the A) chemical synapse.B) electrical synapse.C) axon hillock. D) dendritic membrane.E) synaptic terminal.
C
149) A neuron whose membrane potential shifts closer to threshold is said to be A) hyperpolarized.B) depolarized.C) facilitated. D) repolarized.E) at equilibrium.
C
69) Ion channels that are always open are called ________ channels. A) activeB) gatedC) leak D) regulatedE) local
C
71) Voltage-gated channels are present A) at the motor end plate.B) on the surface of dendrites.C) in the membrane that covers axons. D) on the soma of neurons.
C
73) ________ open or close in response to binding specific molecules. A) Leak channelsB) Activated channelsC) Chemically gated channels D) Voltage-gated channelsE) Voltage-gated and chemically gated channels
C
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 cell C) 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.
C
79) Graded potentials A) 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.
C
86) The sum of the electrical and chemical forces acting on an ion is known as its A) permeability gradient.B) thermodynamic difference.C) electrochemical gradient. D) action potential.E) summation difference.
C
123) Cholinergic synapses release the neurotransmitter A) norepinephrine.B) adrenalin.C) serotonin. D) acetylcholine.E) GABA.
D
137) Which neurotransmitter has a direct effect on opening chloride channels? A) dopamineB) norepinephrineC) serotonin D) GABAE) endorphins
D
139) Which of the following neurotransmitters is a dissolved gas? A) serotoninB) glutamateC) aspartate D) nitric oxideE) histamine
D
145) EPSPs (excitatory postsynaptic potentials) occur when A) 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.
D
68) At the normal resting membrane potential of a typical neuron, its sodium-potassium exchange pump transports A) 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.
D
72) The sodium-potassium ion exchange pump A) 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.
D
74) ________ channels open or close in response to physical distortion of the membrane surface. A) Voltage-gatedB) Chemically gatedC) Active D) Mechanically gatedE) Leak
D
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 channel C) voltage-regulated calcium channelD) chemically-regulated potassium channel E) chemically-regulated sodium channel
D
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.
D
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.
4, 2, 3, 1
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.
4, 2, 6, 7, 1, 8, 3, 5
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.
4, 6, 7, 1, 2, 3, 5
110) Which of the following types of nerve fiber possesses the fastest speed of impulse propagation? A) type AB) type B C) type CD) type DE) type E
A
112) Sensory information from skeletal muscles travels over ________ fibers. A) type AB) type BC) type C D) type DE) type E
A
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 diameter D) a nonmyelinated fiber of 10-μm diameterE) It would be the same in all because of the all-or-none principle.
A
114) The minimum stimulus required to trigger an action potential is known as the A) threshold.B) all-or-none response.C) potential. D) incentive.E) summation.
A
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 refractory C) restingD) lagE) stationary
A
121) Which type of synapse is most common in the nervous system? A) chemicalB) electricalC) mechanical D) processingE) radiative
A
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.
A
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.
A
78) If the sodium-potassium pumps in the plasma membrane fail to function, all of the following occur except A) 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.
A
83) Voltage-gated sodium channels have both an activation gate and a(n) ________ gate. A) inactivationB) ionC) swinging D) repolarizationE) threshold
A
85) A movement of charges in response to a potential difference is called A) current.B) depolarization.C) hyperpolarization. D) action potential.E) electricity.
A
88) The equilibrium potential of potassium is A) -90mV.B) -65mV.C) -70mV. D) +30mV.E) +66mV.
A
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.
A
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.
A
96) A threshold stimulus is the A) 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.
A
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.
A
108) Rapid impulse conduction from "node" to "node" is called A) spatial propagation.B) saltatory propagation.C) divergent propagation. D) synaptic transmission.E) continuous propagation.
B
115) The ________ principle states that the size and speed of the action potential are independent of the stimulus strength. A) thresholdB) all-or-none C) summationD) polarizationE) potential
B
116) The period during which an excitable membrane cannot respond to further stimulation is the ________ period. A) relative refractoryB) absolute refractory C) restingD) lagE) stationary
B
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.
B
133) Adrenergic synapses release the neurotransmitter A) acetylcholine.B) norepinephrine.C) dopamine. D) serotonin.E) GABA.
B
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.
B
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 summation C) inhibition of the impulseD) hyperpolarizationE) decrease in speed of impulse transmission
B
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 facilitation C) spatial summationD) temporal summationE) spatial facilitation
B
151) In one form of presynaptic inhibition the release of ________ inhibits the opening of voltage gated calcium channels in the axon terminus.A) glutamateB) GABA C) serotoninD) dopamineE) aspartate
B
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) choline C) coenzyme AD) calciumE) acetyl-CoA
B
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.
B
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.
B
87) A shift of the resting transmembrane potential toward 0 mV is called A) potential difference.B) depolarization.C) hyperpolarization. D) polarization.E) repolarization.
B
91) The all-or-none principle states that A) 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.
B
94) During repolarization of a neuron A) 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.
B
111) Type ________ fibers have the largest diameter axons. A) S B) F C) A D) B E) C
C
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 sheath C) diameter of the axonD) presence or absence of nodesE) whether or not the impulse begins in the CNS
E
118) The presence of ________ dramatically increases the speed at which an action potential moves along an axon. A) a capsuleB) plasma protein C) neurilemmaD) glial cellsE) myelin
E
120) A neuron that receives neurotransmitter from another neuron is called A) the presynaptic neuron.B) the motor neuron.C) an oligodendrocyte. D) a satellite cell.E) the postsynaptic neuron.
E
126) The effect that a neurotransmitter has on the postsynaptic membrane depends on the A) 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.
E
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 dendrites D) diffusion of sodium ions out of the synaptic terminal E) diffusion of calcium ions into the synaptic terminal
E
140) Which of the following neurotransmitters are known to bind to G-protein coupled receptors?A) epinephrineB) serotonin C) dopamineD) GABAE) All of these bind to G-protein coupled receptors.
E
75) Any stimulus that opens a ________ ion channel will produce a graded potential. A) voltage-gatedB) chemically gatedC) sodium D) mechanically gatedE) All of the answers are correct.
E
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.
E
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 pump D) through chemically gated channels as in neuromuscular transmission E) All of the answers are correct.
E
82) Raising the potassium ion concentration in the extracellular fluid surrounding a nerve cell will have what effect? A) depolarize itB) hyperpolarize it C) 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
E
89) The equilibrium potential of sodium is A) -90mV.B) -65mV.C) -70mV. D) +30mV.E) +66mV.
E
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.
E
