A neuron with a resting membrane potential of -75 mV receives multiple inputs giving rise to the following post-synaptic potentials: -15 mV, 20 mV, -5 mV, 7 mV, and 22 mV. The threshold is -50 mV. What will be the outcome? O a. An action potential (AP) will be generated because there are more positive than negative inputs o b. No action potential because the presence of a single IPSP is sufficient to prevent an AP An action potential (AP) will be generated because the sum exceeds the threshold o d. An action potential (AP) will be generated because the sum of inputs is a positive value o e. No action potential (AP) will be generated because the sum of inputs is below the threshold

A neuron with a resting membrane potential of -75 mV receives multiple inputs giving rise to the following post-synaptic potentials: -15 mV, 20 mV, -5 mV, 7 mV, and 22 mV. The threshold is -50 mV. What will be the outcome? O a. An action potential (AP) will be generated because there are more positive than negative inputs o b. No action potential because the presence of a single IPSP is sufficient to prevent an AP An action potential (AP) will be generated because the sum exceeds the threshold o d. An action potential (AP) will be generated because the sum of inputs is a positive value o e. No action potential (AP) will be generated because the sum of inputs is below the threshold

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

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 2SQE

See similar textbooks

Similar questions

Assume presynaptic excitatory neuron A terminates on a postsynaptic cell near the axon hillock and presynaptic excitatory neuron B terminates on the same postsynaptic cell on a dendrite located on the side of the cell body opposite the axon hillock. Explain why rapid firing of presynaptic neuron A could bring the postsynaptic neuron to threshold through temporal summation, thus initiating an action potential, whereas firing of presynaptic neuron B at the same frequency and the same magnitude of EPSPs may not bring the postsynaptic neuron to threshold.
Conformational changes in channel proteins brought about by voltage changes are responsible for opening and closing Na+ and K+ gates during the generation of an action potential. (True or false?)
Which of the following statements best describes saltatory conduction? a. It inhibits direct neurotransmitter release. b. It transmits the action potential at the nodes of Ranvier andthus speeds up impulses on myelinated axons. c. It increases neurotransmitter release at the presynapticmembrane. d. It decreases neurotransmitter uptake at chemically gatedpostsynaptic channels. e. It removes neurotransmitters from the synaptic cleft.
Sequence the following list of events of a neuronal action potential by placing 1 next to the first event, 2 next to the second event, and so on. a. _____ The activation gates of voltage-gated Na+ channels open, Na+ flood the cytoplasm, and depolarization occurs. b. _____ K+ continue to flow out of the axon until the membrane is hyperpolarized. c. _____ Local potentials cause the membrane to depolarize to threshold. d. _____ The inactivation gates of voltage-gated Na+ channels close as voltage-gated K+ channels open, K+ begin to exit the axon, and repolarization begins. e. _____ Repolarization continues and Na+ channels return to resting
The extracellular sodium [Na+]0 is reduced in the saline bath. Following another current injection in a neuron, the membrane potential changes were recorded. a) Why has the membrane potential changed following the Na+ reduction? b) Why has the current injection produced no action potentials? c) How might you experimentally rescue action potential generation?
Assume a neuron's membrane potential is -60 mV, what's the net consequence on the membrane potential of a 5 picoamp (pA) sodium current that occurs simultaneously with a 5 pA chloride current? a. There's a 5 pA hyperpolarizing current b. There's a 10 pA depolarizing current c. There's a 10 pA hyperpolarizing current d. There's a 5 pA depolarizing current e. There's no change in the membrane potential
Which of the following is TRUE regarding the absolute and relative refractory periods of the action potential (AP)? A. The absolute refractory period may be overcome if enough excitatory stimulation is applied to the neuronal membrane. B. The absolute refractory period is due the closing of the activation gate of voltage gated sodium channels at the peak of the AP. C. The relative refractory period is due to the closing of the activation gate of voltage gated potassium channels during the overshoot phase of the AP. D. The relative refractory period is due the closing of the inactivation gate of voltage gated sodium channels . E. All of the above statements are FALSE.
In a resting neuron, which of the forces listed below will act to push sodium (Na+) ions into the cell? A. All of these answers are correct B. Force of diffusion C. Electrical force D. Sodium-potassium pump E. Osmotatic force F. Both A and B are correct
The axon hillock of a neuron reaches the threshold of excitation and the membrane potential becomes completely reversed. Then, suddenly, the membrane potential begins to return to resting membrane potential. What is the event that triggers this return to resting potential? A. Na+ channels close in a voltage-dependent manner B. Na+ channels close in a time-dependent manner C. Na+ channels close in a chemically-dependent manner D. Na+ channels open in a voltage-dependent manner
In Japan, the consumption of “Fugu” (a kind of sashimi sushi) is considered to be a “manly” act. The danger associated with consuming Fugu is due to the presence of tetrodotoxin, a potent neurotoxin found in various organs of the pufferfish. a. If the Fugu toxin on a neuron “driving” toward Ex of most permeable ion, is an action potential more or less likely under these conditions? b.Which (flaccid or tonic) is the result in this case? What would be the associated physical symptoms of this condition?
Which of the following is the role of axonal Calcium (Ca2+) channels in neuronal communication at the synapse? a) they inhibit the action potential causing it to stop b) Calcium channels have no role in this process c) by allowing calcium to exit the cell, they promote the propagation of action potential across the synapse by creating depolarization d) by blocking calcium entrance, they mediate the contraction of presynaptic axon to facilitate movement e) when they open, calcium enters the presynaptic terminal, promoting fusion of neurotransmitter vesicles with presynaptic membrane, and release of neurotransmitters to the synaptic cleft
Post synaptic neurons membrane potentials are less negative than resting membrane potentials when this occur A. Creates a new set point for the resting membrane potential B. Has a lower propensity to produce an action potential C. Reacts by generating action potential D. Higher chance of reaching the potential threshold