The Resting Potential It is the membrane potential of a nerve or muscle cell

The resting potential it is the membrane potential of

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The Resting PotentialIt is the membrane potential of a nerve or muscle cell, subject to changes when activated.K+gradients maintained by the Na+/K+-ATPase are responsible for resting potential.Nernst equation used to calculate the voltage equivalent of the concentration gradients for specific ions.Negative resting membrane potential is near the negative Nernst potential for K+and far from the positive Nernst potential for Na+.
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Measuring a membrane’s resting potential
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The Action Potential (AP) When excitable cells are stimulated, voltage-gated Na+ channels open, triggering the AP. Na + channels are inactivated immediately following an AP, producing a short refractory period when the membrane cannot be stimulated. Excitable membranes exhibit all-or-none behavior.
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Formation of an action potential
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Formation of an action potential
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The structure of a nerve cell __________ are specialized cells for information transmission using changes in membrane potentials. __________ receive incoming information. ___________ contains the nucleus and metabolic center of the cell. The __________ is a long extension for conducting outgoing impulses. Most neurons are wrapped by ______________
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Propagation of Action Potentials as an Impulse APs produce local membrane currents depolarizing adjacent membrane regions of the membrane that propagate as a nerve impulse . Speed Is of the Essence : Speed of neural impulse depends on axon diameter and whether axon is myelinated. Resistance to current flow decreases as diameter increases. Myelin sheaths cause saltatory conduction .
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Propagation of an impulse
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Saltatory Conduction
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Neurotransmission: Jumping the Synaptic Cell _______________________ communicate with ____________________ at a specialized junction, called the ____________ , across a gap ( ___________ ). Chemicals ( __________________ ) released from the presynaptic cleft diffuse to receptors on the postsynaptic cell.
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Neurotransmission: Jumping the Synaptic Cleft Bound transmitter can depolarize (excite) or hyperpolarize (inhibit) the postsynaptic cell. Transmitter action is terminated by reuptake or enzymatic breakdown.
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The sequence of events during synaptic transmission with acetylcholine as the neurotransmitter
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Actions of Drugs on Synapses Interference with the destruction or reuptake of neurotransmitters can have dramatic physiological and behavioral effects. Examples include: antidepressants, recreational drugs
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