Test
Practice Exam 1
Preguntas del test (40)
1In synaptic integration, summation can take place between:
- AIPSPs and other IPSPs but temporal summation only
- BIPSPs and other IPSPs or EPSPs both temporal and spatial summation
- CEPSPs and other EPSPs but spatial summation only.
- Dchoices 1 and 2
- Echoices 1, 2 and 3
2During plateau action potential:
- Athe delayed rectifier channels are fully open
- Bthe inward rectifier channels are closed
- Cthe Ca2+ channels are open
- Dchoices 1 and 2
- Echoices 2 and 3
3About after-potentials of an action potential evoked following repetitive activity:
- Athe after-depolarization is partly due to slowing down of K+ efflux
- Bthe after-hyperpolarization is partly due to excessive extrusion of Na+ by the pump.
- Cthe after-hyperpolarization is partly due to excessive efflux of K+
- Dchoices 1 and 2
- Echoices 1, 2 and 3
4About transport within neuron: particles can be transported within the cytoplasm:
- Afrom the nerve terminals to the cell body and is called retrograde.
- Bfrom the cell body to the nerve endings and is called orthodromic.
- Cfrom the nerve terminals to the cell body and is called antidromic.
- Dchoices 1 and 2
- Echoices 1, 2 and 3
5The Na+-K+ transporter:
- Apumps 3 Na+ out and 2 K+ in through their respective channels
- Bcreates an increase in the negativity of the RMP
- Cis a form of secondary active transport
- Dchoices 1 and 3 are true
- Enone of the above choices are true
6Amyotrophic lateral sclerosis (ALS):
- Alesions are more localized whereas those of multiple sclerosis (MS) are diffused
- Blike MS, it demyelinate nerves only in the CNS
- Clike MS, may lead to paralysis
- Dchoices 1 and 2
- Echoices 1, 2 and 3
7The resting membrane potential of a nerve becomes:
- Aless negative when Na+ concentration in extracellular fluid [Na]o is increased
- Bless negative when [K+]o is increased
- Cmore negative when [Na+]o is increased
- Dmore negative when [Ca2+]o is increased
- Enone of the above
8If the K+ delayed rectifier channels are blocked by TEA then the nerve AP would:
- Alook similar to the cardiac ventricular AP
- Blook like a pacemaker AP
- Cbe blocked
- Dlook like a skeletal muscle AP
- Enone of the above
9The nerve action potential:
- Aduring its up-stroke the Na+/K+ permeability ratio is small
- Bduring its down-stroke (repolarization), the K+/Na+ permeability ratio is small
- Cits upstroke is due to Na+ activation
- Dchoices 1 and 2
- Echoices 2 and 3
10The compound action potential:
- Acannot be recorded form a single squid giant axon
- Bis not an all-or-none response
- Ccan be only be recorded in the PNS
- Dchoices 1 and 2.
- Echoices 1, 2 and 3.
11The resting membrane potential:
- Asupplies “potential energy” for firing action potentials
- Bcan be calculated by using a modified Nernst equation
- Csupplies needed energy for the Na-K pump
- Dchoices 1 and 2
- Echoices 1,2 and 3
12Subthreshold depolarization of the axon membrane
- Aremains the same size at each point along the axon membrane
- Bproduces a local response
- Cdecreases in size as it sweeps along the membrane
- Dchoices 1 and 2
- Echoices 2 and 3
13In a myelinated axon, at which point along the axon can ion enter and leave the membrane?
- Athe membrane segment under the Schwann cell wrapping
- Bthe axon hillock
- Cthe node of Rnavier
- Dchoices 1 and 2
- Echoices 2 and 3
14Which of the following is an advantage of salutatory conduction?
- Afaster conduction
- Bless transmitter is required to send a message across the synapse
- Cconservation of energy: i.e. less energy is expended by the membrane
- Dchoices 1 and 2
- Echoices 1 and 3
15The essential event (s) for the release of neurotransmitter from presynaptic membrane is:
- Athe arrival of an EPSP at the axon terminal
- Binflux of calcium ions into the axon terminal
- Cinflux of K ions into the axon terminal
- Dchoices 1 and 2
- Echoices 1, 2 and 3
16Presynaptic inhibition
- Acan be produced by chloride efflux at certain nerve terminals
- Bit may involve AMPA receptors
- Clonger lasting than postsynaptic inhibition
- Dchoices 1 and 2
- Echoices 1 and 3
17Which of the following will produce an EPSP?
- Aopening sodium channels
- Bclosing sodium channels
- Copening potassium channels
- Dopening chloride channels
- Eclosing calcium channels
18Which of the following is true
- Aoligodendrocytes exist in the brain
- BSchwann cells provide myelin for peripheral nerve axons
- Ca single Schwann cell wraps a single segment of a peripheral nerve
- Da single oligodendrocytes can mylinate up to 50 segments of axon membrane
- Eall of the above are correct
19_________ generate scar tissue which impedes regeneration of damaged axons
- Aastrocytes
- BSchwann cells
- Caxon terminals
- Doligodendrocytes
- Edendrites
20Which of the following represents the normal order of activation in neuronal transmission?
- Aaxon∏ dendrites∏soma∏axon terminals
- Baxon terminals ∏soma∏ axon∏ dendrites
- Cdendrites∏soma∏ axon∏ axon terminals
- Dsoma∏ axon∏ dendrites∏axon terminals
- Edendrites∏ axon terminals∏ soma∏ axon
21The ___________ is defined as the difference in electrical charge between the intracellular side and the extracellular side of an inactive nerve cell membrane.
- Alocal potential
- BEPSP
- Caction potential
- Dmembrane potential
- EEPP
22An electric stimulus applied to an axon that moves the membrane potential from –70 to –45 mV will result in:
- Alocal potential
- BEPSP
- Caction potential
- Dmembrane potential
- EEPP
23Match the correct synaptic event with each ion channel action:
- Aentry of a negative ion-hyperpolarization
- Bentry of a positive ion-hyperpolarization
- Cexit of a positive ion-depolarization
- Dexit of a negative ion-hyperpolarization
- Echoices 1 and 3 are correct
24Which of the following events contribute to the restoration of the membrane potential from the peak of action potential
- Aclosure of sodium channels
- Bpotassium ions move out of the cell
- Cthe sodium-potassium transporter
- Dchoices 1 and 2
- Echoices 1, 2 and 3
25Regarding types of synaptic transmission: _______ is an example of ________
- Aglutamate NMDA receptor-fast synaptic transmission
- BmACh receptor-fast synaptic transmission
- Cserotonin 5-HT3 receptor-slow synaptic transmission
- DGABAa receptor-slow synaptic transmission
- Eall of the above correct correct
26Compared with types A and B fibers; type C fibers are:
- Aunmyelinated
- Bwith the slowest speed of conducttion
- Csensitive to the action of local anesthetics
- Dchoices 1 and 2
- Echoices 1, 2 and 3
27Sodium channels, K channels and Na-K pumps exist on all parts of:
- Amyelinated nerve membrane
- Bunmyelinated nerve membrane
- Cmuscle cell membrane
- Dchoices 1 and 2
- Echoices 2 and 3
28The process that blocks all postsynaptic potentials is:
- Ablockade of the postsynaptic receptors.
- Binhibition of transmitter release.
- Cdegradation of the transmitter molecule by a native enzyme.
- Dchoices 1 and 2
- Echoices 1, 2 and 3
29The “all-or-none law”:
- Adoes not apply to ventricular action potential
- Brefers to the observation that an action potential is evoked whenever the membrane potential reaches threshold
- Cdoes not apply to IPSP
- Dchoices 1 and 2
- Echoices 1, 2 and 3
30Sodium ions:
- AAre involved directly in the production of action potential
- Bcross the membrane through their specific channels during action potential by simple diffusion
- Cresponsible for formation of EPP
- Dchoices 1 and 2
- Echoices 2 and 3
31Which of the following will "neutralize" an EPSP?
- Afurther opening a sodium channel
- Ballowing intracellular anions to leave the cell
- Cclosing a potassium channel
- Dopening a chloride channel
- Echoices 2 and 4.
32Which of the following statements is correct?
- ACO2 and O2 are not lipid soluble substances.
- BSome drugs (e.g. endomethacin) stabilize lysosomal membrane, which may explain their anti-
inflammatory action - Cspecific Na+ channels are the same as acetylcholine channels.
- DFast axonal transport is directly involved in conduction of impulses.
- EAll of the above are incorrect.
33Which of the following will produce an IPSP?
- Aopening sodium channels only
- Bopening chloride channels only
- Copening potassium channels only
- Dchoices 1 and 2
- Echoices 2 and 3
34The membranes that most commonly form synapses are the ______ and _______
- Amotor nerve terminals ; skeletal muscle
- Baxon terminals; dendrites
- Caxon terminals; glial
- Dchoices 1 and 2
- Echoices 1, 2 and 3
35About the reversal potential of a nerve:
- Adifferent excitable tissues have different reversal potentials
- Bit is the highest positive value the AP reaches
- Cis also called the threshold
- Dchoices 1 and 2
- Echoices 2 and 3
36What type of refractory periods occurs during:
- AEPP- relative
- BEPSP-absolute
- CmEPP-realtive
- DmEPSP-absolute
- Enone of the above is correct
37The process which terminates the action of ACh at the neuromuscular junction is:
- Adisruption of the postsynaptic receptor.
- Benzymatic degradation by ACh-esterases.
- Cinhibition of ACh synthesis.
- Dchoices 1 and 2
- Echoices 1, 2 and 3
38A drug that opens potassium channels of an axon and causes a 5 mV change in resting membrane potential (RMP):
- Athat change is called depolarization
- Bcauses a 5 mV increase in the amplitude of evoked action potential
- Cthat change is called hyperpolarization
- Dchoices 1 and 2
- Echoices 2 and 3
39Conduction velocity of a nerve can be calculated if the following information is provided:
- Aduration of action potentials (AP) and length of nerve
- Bthe latent period and length of nerve between electrodes
- Cstrength of the stimulus and length of nerve
- Dthe refractory periods and length of nerve
- Enone of the above, more information is needed.
40Which of the following statement(s) about compound action potential is/are False?
- ACompound action potential is seen when a single axon is stimulated
- BThe first peak in a compound action potential belongs to A fiber type
- CA compound action potential is an all-or-none phenomenon
- Dchoices 1 and 2
- Echoices 1 and 3
Información
- Descripción
- OSLS
- Autor
- Justin Miller
- Idioma
- English
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