Action potentials do not occur in the soma of a neuron because
a.it lacks voltage gated sodium channels |
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b.it lacks leaky potassium channels |
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c.it lacks leaky sodium channels |
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d.it lacks chemically gated channels |
a. It lacks voltage gated Na+ channels. Soma of Neuron is also called cell body or perikaryon or neurocyton. It doesn’t play an important role in generation of action potential .it only transmits the signal from dendrites to axon hillock from there to axon terminals. Functions of cell body. It consists of several organelles and nucleus. The nucleus consists of DNA for cellular activity. Types of cell bodies. 1. Unipolar neurons 2.multipolar neurons. 3. Bipolar neuron.
Action potentials do not occur in the soma of a neuron because a.it lacks voltage gated...
Which choice represents transport proteins in a neuron? a. Voltage-gated channels and passive transporters b. Passive transporters and sodium-potassium cotransporters c. Sodium-potassium cotransporters, passive transporters, and voltage-gated channels d. Voltage-gated channels and passive transporters e. Sodium-potassium cotransporters and voltage-gated channels
An action potential does not move back wards in the axon because.. a.Voltage-gated sodium channels behind the action potential are inactivated. b. Potassium leak channels no longer let potassium ions through c. Voltage-gated sodium channels are open d. Mechanically-gated channels prevent outflow of sodium e. Voltage-gated potassium channels are closed
A mutation causes the incorporation of fewer voltage-gated sodium channels into the membrane of a neuron. a) What effect will this mutation have on synaptic potentials if this neuron receives excitatory input? b) What effect will this mutation have in the axon hillock area?
Order the following events that occur in a neuron in response to a stimulus Sodium Potassium Pumps and Potassium Leak Channels re-establish the resting potential Voltage Gated Potassium channels close The inside of the cell becomes more negative than the original resting potential V Voltage Gated Sodium channels open Sodium ions rush into the cell The inside of the cell becomes temporarily positive Votage Cated Potatalum channels open which causes potassium to flood out of the cell
How would you alter sodium and/or potassium voltage-gated channels to preserve their dependence on voltage, but eliminate action potentials? Effect of altering Na/K channels
D 5. Imagine that, using a microscopic needle, you inject a drug directly into a neuron that blocks half of the voltage-gated K+ channels in a neuron. What would be the effect on the action potential of a neuron? Prolonged (longer) action potential because of slower K+ diffusion No action potential would occur because K+ cannot enter the cell Action potentials will be higher in amplitude Action potentials will start at the dendrites
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....
1. The adrenal medulla is excited by the parasympathetic preganglionic neuron during times of immediate stress. (true or false) 2. The activation gate of the voltage-gated sodium channel closes after a certain amount of time regardless of the membrane potential. (true or false) 3. Acetylcholine binds to voltage-gated sodium ion channels to initiate a graded potential. (true or false) 4. Action potentials can occur in the axon terminal. (true or false) 5. Opening a chloride ion channel in the cell...
During the propagation of an action potential, what would be the effect of a mutation in the voltage-gated Na+-channels that does not allow “inactivation” phase to occur, such that these channels go directly from open to closed conformations? a) The neuron with the mutant Na+ channels will start letting in calcium ions and generate a calcium-based action potential that is stronger than the sodium-based action potential. b) The neuron with the mutant Na+ channel will exhibit a reverse electrochemical gradient...
A Draw graphs showing the effect on action potentials in a cell following effective doses of each of the listed neurotoxins. Assume that the cell is normally brought to threshold by an electrical stimulus applied to it, so that any abnormality is due to the toxin. Precise values for voltage and duration are not important, just a general trend in how the action potential may be different from normal 1. puffer fish poison (blocks voltage-gated sodium channel activation) (25 Points)...