Charge from depolarization along the axon reaches the axon terminal, but there is a lack of neurotransmitter release. Which of the following would cause this? Group of answer choices A. Lack of Na+ in the synaptic cleft B. Lack of Ca2+ in the synaptic cleft C. Reduced amount of K+ at the axon terminal D. Lack of voltage-gated sodium channels in the axon terminal

Charge from depolarization along the axon reaches the axon terminal, but there is a lack of neurotransmitter release. Which of the following would cause this? Group of answer choices A. Lack of Na+ in the synaptic cleft B. Lack of Ca2+ in the synaptic cleft C. Reduced amount of K+ at the axon terminal D. Lack of voltage-gated sodium channels in the axon terminal

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter5: The Central Nervous System

Section: Chapter Questions

Problem 12RE

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Similar questions

If a graded receptor potential made the resting membrane potential of the axon more negative, you would expect: Subsequent action potentials to be reduced in their amplitude It to be easier for this axon to reach threshold voltage It to be more difficult for this axon to reach the threshold voltage Subsequent action potentials to be shorter in duration No change in the ability of this axon to reach threshold voltage
Which of the following types of ion movements across an axon membrane would cause theaction potential to change during the interval from 0.2 ms to 0.4 ms?A. Sodium ions moving into the axonB. Sodium ions moving out of the axonC. Potassium ions moving into the axonD. Potassium ions moving out of the axon
As the action potential (AP) propagates away from the axon hillock, why does it continue in one direction (downstream)? the region behind the AR is in absolute refractory period the region in front of the AP is in absolute refractory period they travel the path of least resistance the region behind the AP runs out of NA+ ions Both A and B
Which of the following would increase the speed of a nerve impulse along an axon?A. Decreasing the spacing between the nodes of the axonB. Decreasing the resistance between nodesC. Decreasing the thickness of the myelin sheathD. Increasing the resting potential of the axon
Which of the following combinations of spatial summation of postsynaptic potentials (PSP) would result in an action potential in a typical neuron? The voltage given for each PSP is measured as it reaches the axon hillock. Axon A EPSP 25 mV & axon B IPSP 10 mV Axon A IPSP 25 mV & axon B EPSP 10 mV Axon A IPSP 5 mV & axon B IPSP 5 mV Axon A EPSP 5 mV & axon B EPSP 5 mV
In the laboratory, researchers can apply an electrical stimulus at any point along the axon, making action potentials travel in both directions from the point of stimulation. An action potential moving in the usual direction, away from the axon hillock, is said to be traveling in the orthodromic direction. An action potential traveling toward the axon hillock is traveling in the antidromic direction. If we started an orthodromic action potential at the axon hillock and an antidromic action potential at the opposite end of the axon, what would happen when they met at the center? Why?
A F B C- D Match the labelled synapse structure with the correct structure or function. Place the correct number in each blank. Use each letter only once. Synaptic vesicle containing the neurotransmitters Postsynaptic membrane of the dendrite Synaptic cleft Receptor site for the neurotransmitter on the dendrite Axon terminal Mitochondria, which supply ATP for synthesis of transmitters
Which of the following statements best describes the properties of a myelinated axons? The axon has an even distribution of ion channels but it is covered by layers of myelin apart from short sections termed the nodes of Ranvier where there is no myelin. The action potential is able to jump from node to node because the myelin sheath increases the length constant. There are very few ion channels underneath the myelin. The density of Na+ channels at the nodes of Ranvier is very high but there are no K+ channels in myelinated axons. The myelin sheath increases the rate of action potential conduction because the action potential underneath the myelin sheath travels faster than an action potential in an unmyelinated axon.
Which of the following are the likely explanations for the failure of a postsynaptic neuron to trigger an action potential? Select all that apply. The EPSPs are neutralized by the neurotransmitter The summation of IPSPs and EPSPs is insufficient to depolarize the cell to threshold The synapses generating the EPSPs are too close to the axon hillock The synapses generating the EPSPs are too far from the axon hillock
Which of the following is comparable to a negative feedback cycle? opening of voltage-gated Na" channels in response to a depolarizing graded potential movement of K* through leak channels opening of voltage-gated K* channels in response to a depolarizing graded potential operation of the Na -K ATPase at rest opening of voltage-gated Ca- channels in response to an action potential arriving at the axon terminal
Which of the following is FALSE about action potentials? At resting potential, there are more potassium channels open and most sodium channels are closed. Depolarization is due to the flow of Na+ out of the axon via voltage-gated Na+ channels. Hyperpolarization is due to continued loss of K+ from the axon. During repolarization, K+ flows out of the axon along its concentration gradient. Resting membrane potential is primarily established by the Na+/K+ pump.
The falling phase of the action potential is due to: Na+ influx through voltage-gated Na+ channels. O Na* efflux through voltage-gated Na* channels. OK* influx through voltage-gated K+ channels. O K+ efflux through voltage-gated K channels. O Nat influx through Na* leak channels. Na efflux through Na+ leak channels. O K+ influx through K+ leak channels. O K+ efflux through K+ leak channels.