For action potentials and membrane potentials: Describe how the membrane depolarizes and then repolarizes, how an action potential opens voltage gated channels in front of it and thus passes the action potential further and further down the neuron.
For action potentials and membrane potentials: Describe how the membrane depolarizes and then repolarizes, how an...
Compare and contrast graded potentials and action potentials, with particular attention to their locations in the neuron and the ions and ion channels involved in each. Label a voltage-versus-time diagram of an action potential with the ions involved in each phase, the direction of their movement across the membrane, and the terms depolarize, repolarize, and hyperpolarize. Describe the physiological process involved in the conduction (propagation) 2 of an actic potential, including the types and locations of the ion channels involved....
Multiple Choice Action potentials A) rapid reversal of membrane potential B) occurs at nodes of ranvier C) occurs along myelin sheath D) dependent on voltage gated channels E) occurs at axon hillock
1. What triggers the opening of each of the different channels: ligand-gated K+ channels, ligand-gated Na+ channels, ligand-gated Cl- channels, voltage-gated Na+ channels, voltage-gated K+ channels, voltage-gated Ca2+ channels. 2. What happens to membrane potential in the immediate area where the channel is located when the channel opens and ions flow through? 3. Since graded and action potentials happen in different locations on the neuron, explain what has to happen to link these different events together.
CNCORA 6 of 10 > Action potentials in neurons involve opening and closing of voltage-gated Nat and K ion channels. Place the events of an action potential in order, starting and ending with a cell at its resting membrane potential. Resting state Return to resting state Answer Bank A graded potential brings the membrane to threshold potential. Fast Na+ and slow K* channels are activated. Nat rushes into the cell, causing membrane depolarization. K channels close slowly, resulting in hyperpolarization....
What is a resting potential? Is it positive or negative? The resting potential is mainly due to the main _____-charged large molecules stuck inside the neuron. The Na+/K+ pump pushes Na+ _____ of the cell and K+ ____ of the cell (in or out for each ion) Where is K+ concentrated, inside or outside of the neuron? Where is Na+ concentrated, inside or outside of the neuron? The action potential starts with an rise in membrane voltage. This is due...
Action potentials do not occur in the soma of a neuron because a.it lacks voltage gated sodium channels b.it lacks leaky potassium channels c.it lacks leaky sodium channels d.it lacks chemically gated channels
3. Many neurons contain "delayed K channels". Like voltage-gated Nat channels, these voltage-gated K+ channels open in response to a rise in membrane potential and then undergo inactivation. However, opening of the voltage-gated K channels lags behind opening of the voltage-gated Na channels. a) Why does neuronal function require the voltage-gated K channels to open more slowly than the voltage-gated Na channels? b) Compared to a neuron that lacks voltage-gated K channels, what differences would you expect in the shape...
5. Did you notice that during the action potential the neuron membrane potential reaches -90mV and stops? How/why does it stop at -90mV? Why doesn't it get more negative than -90mV? Hint: When the voltage-gated K+ channels are open on a neuron, there are so many voltage- gated K+ channels open that in reality you can think of the cell as being only permeable to K+. It's the main ion moving. Based on this and what we talked about on...
For each phase of an action potential, indicate the ion channel most responsible for the membrane potential change that occurs during the phase. Action Potential Phases Ion Channels Depolarization phase Repolarization phase Hyperpolarization phase Voltage-gated potassium channels Chemically-gated sodium channels Chemically-gated potassium channels Voltage-gated sodium channels
Which of the following statements about action potentials is incorrect? O a) During an action potential, the efflux of Kions causes the inside of cells to become more positive (depolarized). B) When critical threshold is reached an action potential is triggered C) Voltage gated channels are required to reach critical threshold D) Sodium ions diffuse across the membrane to cause depolariza D U E)Kions continue to efflux after resting membrane is reached to cause repolarization ause