Which two ideas about ion channels of a neuron at its resting potential are true? O ion channels are always closed, but ions move closer to the channels during excitation O ion channels open in response to stimuli and then close simultaneously, in unison O ion channels are always open, but the concentration gradients of ions frequently change O ion channels open and close depending on chemical messengers and are nonspecific as to which ion ca traverse them ion channels open and close depending on stimuli and are specific as to which ion can traverse them

Which two ideas about ion channels of a neuron at its resting potential are true? O ion channels are always closed, but ions move closer to the channels during excitation O ion channels open in response to stimuli and then close simultaneously, in unison O ion channels are always open, but the concentration gradients of ions frequently change O ion channels open and close depending on chemical messengers and are nonspecific as to which ion ca traverse them ion channels open and close depending on stimuli and are specific as to which ion can traverse them

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

Watch this video (http://openstaxcollege.org/l/summation) to learn about summation. The process of converting electrical signals to chemical signals and back requires subtle changes that can result in transient increases or decreases in membrane voltage. To cause a lasting change in the target cell, multiple signals are usually added together, or summated. Does spatial summation have to happen all at once, or can the separate signals arrive on the postsynaptic neuron at slightly different times? Explain your answer.
You learned in this chapter that Na+/K+ active transport pumps in the plasma membrane of the axons are responsible for creating the imbalance between Na+ and K+ inside and outside of the neuron that produces the resting membrane potential. In early research studying the role of ions and the involvement of active transport of ions in neural signaling, investigators used the giant axon of a squid as a model. The diameter of a giant axon is far greater than that of a mammalian axon, which enabled researchers to isolate it easily and use it in in vitro experiments. In one early experiment, researchers investigated the active transport of Na+ out of the axon in response to the presence of cyanide. Experimentally they hooked up a section of axon to a syringe, immersed the axon in artificial seawater, introduced radioactive 22Na (as 22NaCl) into the axon, and then quantified the transport of 22Na out through the axons plasma membrane. The rate of 22Na transport out of the axon was determined by measuring the radioactivity released into the fluid sur- rounding the axon over a period of time. The Figure shows the results of the experiment. What is the effect of cyanide on Na1 transport out of the squid axon? How do the data show the effect? Source: P. C. Caldwell et al. 1960. The effects of injecting energy-rich phosphate compounds on the active transport of ions in the giant axons of Loligo. The Journal of Physiology 152:561590. Cengage Learning 2017
Visit this site (http://openstaxcollege.org/l/nervetissue3) to learn about how nervous tissue is composed of neurons and glial cells. The neurons are dynamic cells with the ability to make a vast number of connections and to respond incredibly quickly to stimuli and to initiate movements based on those stimuli. They are the focus of intense research as failures in physiology can lead to devastating illnesses. Why are neurons only found in animals? Based on what this article says about neuron function, why wouldnt they be helpful for plants or microorganisms?
View the University of Michigan Webscope (http://openstaxcollege.org/l/nervefiber) to see an electron micrograph of a cross-section of a myelinated nerve fiber. The axon contains microtubules and neurofilaments, bounded by a plasma membrane known as the axolemma. Outside the plasma membrane of the axon is the myelin sheath, which is composed of the tightly wrapped plasma membrane of a Schwann cell. What aspects of the cells in this image react with the stain that makes them the deep, dark, black color, such as the multiple layers that are the myelin sheath?
Would anyone be able to explain these different channels? I would like an explanation as to why voltage gated membranes are associated with axon membranes (although it's prob because of membrane potential differences and depolarization/hyperpolarization?), why ligand gated channels are primarily at synapses (via neurotransmitters?), etc.
IPSP differs from EPSP in :-a- being of shorter durationb- being unable o summate spatiallyc- moving the membrane potential away from thresholdd- depending upon opening of voltage K + channels
How do Na + enter a neurone when initiating an action potential? A) voltage- gated Na+ facilitated transporterB) a gated Na+ pumpC) the legend geted Na +channelD) a voltage- gated Na+ channel K) The Na+ /K+ATPage
Which of the following is the most direct result of depolarizingthe presynaptic membrane of an axon terminal?(A) Voltage-gated calcium channels in the membrane open.(B) Synaptic vesicles fuse with the membrane.(C) Ligand-gated channels open, allowing neurotransmittersto enter the synaptic cleft.(D) An EPSP or IPSP is generated in the postsynaptic cell.
Ordinarily, a neuron’s trigger zone is activated before any other part ofan axon, so a wave of action potentials occurs as sodium channelsopen in the direction of the synaptic terminal. What would happen ifyou artificially stimulated an axon to reach threshold potential midwayalong its length rather than at the trigger zone?a. Action potentials would occur in the direction of the synapticterminal.b. No action potentials would occur.c. Action potentials would occur in the direction of the trigger zone.d. Both a and c are correct.
1.A poison causes a drastic rise inE value with stimulation of the membrane.Thereafter membrane is slow to return towards resting membrane potential and levels off several millivolts above the threshold potential. This poison has likely affect which feature of the membrane? a) voltage gated na+ channels. b) voltage gated K+ channels. c) Na+/K+ Atp pump 2. All cell membrane demonstrate action potential if stimulated enough? True/False. 3. how many peaks are there in a compound action potential? a)2. b)4 c)6 d)8 4. Increasing the ionic concentration in the salt bridge results in E value increase to a point after which it plateeus. This is evidence brownian movement at work in the ionic solution that is keeping from energy flowing through the bridge with the fidelity that is seen in the metal bridge? True/ False 5. All cell membrane demonstrate action potential if stimulated enough? True or False.
Excitatory neurons A and B both synapse with neuron C. Neuron A releasesa neurotransmitter, and neuron B releases the same type and amount ofneurotransmitter plus a neuromodulator that produces EPSPs in neuron C.Action potentials produced in neuron A alone can result in action potentialproduction in neuron C. Action potentials produced in neuron B alone alsocan cause action potential production in neuron C. Which results in moreaction potentials in neuron C, stimulation by only neuron A or stimulationby only neuron B? Explain.
Which of the following is true about the conduction of action potentials? a. Thicker axons are faster because there is more surface area on thicker axons. b. Myelin speeds conduction because the glial cells add voltage gated Na+ channels to the neuron. c. Diffusion of Na+ ions between the Nodes of Ranvier happens faster than the wave of opening and closing membrane proteins can travel. d. Neurons that don’t have myelin sheaths undergo saltatory conduction e. Action potentials move slowly.