Term
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Definition
| electrical potential difference across the cell membrane |
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Term
| resting membrane potential |
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Definition
| membrane potential in a cell at rest (not stimulated) |
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Term
| millivolts of resting membrane potential |
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Definition
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Term
| resting membrane potential is established by 3 main ions |
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Definition
| sodium, potassium, chloride |
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Term
| [Na]i: intracellular sodium concentration |
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Definition
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Term
| [Na]o: extracellular sodium concentration |
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Definition
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Term
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Definition
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Term
| [K]i: intracellular potassium concentration |
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Definition
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Term
| [K]o: extracellular potassium concentration |
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Definition
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Term
| permeability of potassium |
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Definition
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Term
| what plays the biggest role in determining resting membrane potential? |
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Definition
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Term
| [Cl]i: intracellular chloride concentration |
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Definition
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Term
| [Cl]o: extracellular chloride concentration |
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Definition
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Term
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Definition
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Term
| 2 Factors that dictate resting membrane potential |
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Definition
1) magnitude of the concentration gradients of ions
2) permeabilities of the membrane to ions |
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Term
| What leaks passively into the cell during resting conditions? |
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Definition
| Na+ (permeability = small) and Cl- (permeability = large) |
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Term
| What leaks passively out of the cell during resting conditions? |
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Definition
| K+ (permeability = large) |
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Term
| Increase extracellular Na+ |
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Definition
*Vm becomes more positive(depolarization)
increase the gradient for Na to leak into the cell |
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Term
| Increase extracellular K+ |
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Definition
*depolarization
decrease the gradient for K to leak out of the cell |
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Term
| Increase extracellular Cl- |
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Definition
*causes Vm to become more negative (hyperpolarization)
increase the gradient for Cl to leak into the cell |
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Term
| Decrease extracellular Na+ |
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Definition
*hyperpolarization
decreases the gradient for Na to leak into the cell |
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Term
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Definition
*hyperpolarization
increases gradient for K to leak out of the cell |
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Term
| Decrease extracellular Cl- |
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Definition
*depolarization
decrease the gradient for Cl to leak into the cell |
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Term
| Increase intracellular Na |
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Definition
*hyperpolarization
decreases the gradient for Na to leak into the cell |
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Term
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Definition
*hyperpolarization
increases the gradient for K to leak out of the cell |
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Term
| Increase intracellular Cl |
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Definition
*depolarization
decrease the gradient for Cl to leak into the cell |
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Term
| Decrease intracellular Na |
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Definition
*depolarization
increase the gradient for Na to leak into the cell |
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Term
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Definition
*depolarization
decrease the gradient for K to leak out of the cell |
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Term
| Decrease intracellular Cl |
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Definition
*hyperpolarization
increases the gradient for Cl to leak into the cell |
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Term
| at rest, the cell is most permeable to |
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Definition
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Term
| increase the permeability of Na+ |
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Definition
| increase the movement of Na into the cell = depolarization |
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Term
| decrease the permeability of Na+ |
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Definition
| decrease the movement of Na into the cell = hyperpolarization |
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Term
| increase the permeability of K+ |
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Definition
| increase the movement of K out of the cell = hyperpolarization |
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Term
| decrease the permeability of K+ |
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Definition
| decrease the movement of K out of the cell = depolarization |
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Term
| increase the permeability of Cl- |
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Definition
| increase the movement of Cl into the cell = hyperpolarization |
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Term
| decrease the permeability of Cl- |
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Definition
| decrease the movement of Cl into the cell = depolarization |
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Term
| action potential (location) |
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Definition
| occurs solely in excitable cells |
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Term
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Definition
| local, very large and very rapid changes in resting membrane potential |
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Term
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Definition
| depolarized resting membrane potential that must be reached to elicit an action potential |
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Term
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Definition
| period of time when a cell fails to respond to a stimulus of threshold intensity |
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Term
| absolute refractory period |
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Definition
| period of time when no action potential can be elicited |
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Term
| absolute refractory period (when) |
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Definition
| occurs during the repolarization phase due to the inactivation of Na+ channels |
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Term
| relative refractory period |
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Definition
| possible to elicit an action potential during this period of time even though a greater than threshold stimulus is needed |
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Term
| relative refractory period (when) |
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Definition
| occurs during the after-hyperpolarization phase [most Na+ channels begin to activate and most K+ channels can be opened or are still opened] |
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Term
| action potential conduction |
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Definition
| spread of action potentials along a membrane |
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Term
| velocity in axons depends on |
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Definition
| fiber diameter and myelin |
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Term
| rate of conduction velocity |
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Definition
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Term
| rate of saltatory conduction |
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
| maximum number of action potentials |
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Term
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Definition
| no further increase in action potentials |
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Term
| electrical synapses are formed by |
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Definition
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Term
| a single connexon is formed by |
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Definition
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Term
| 2 functions of electrical synapses |
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Definition
1) synchronization between adjoining cells
2) rapid passage of info between two adjoining cells |
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Term
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Definition
| membrane at the synapse that is carrying information |
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Term
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Definition
| membrane at the synapse that is receiving the information |
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Term
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Definition
| reuptake by presynaptic membrane or astrocytes via endocytosis |
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Term
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Definition
| resting membrane potential change in postsynaptic membrane due to the binding of neurotransmitter to postsynaptic membrane receptors |
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Term
| excitatory postsynaptic potential (EPSP) |
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Definition
| caused by depolarizing current through the postsynaptic membrane (influx of cations [K]or efflux of anions [Na]) |
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Term
| inhibitory postsynaptic potential (IPSP) |
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Definition
| caused by hyperpolarizing current through the postsynaptic membrane (influx of anions(Na) or efflux of cations [K]) |
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Term
| summation of postsynaptic potential |
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Definition
| integrated sum of EPSPs and IPSPs; determines Vm change |
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Term
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Definition
| when multiple postsynaptic potentials from the same synapse converge at about the same time |
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Term
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Definition
| when multiple postsynaptic potentials from different synapses converge at about the same time |
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Term
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Definition
| ability of some component of a synapse to change |
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Term
| synaptic plasticity can cause |
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Definition
1) decrease or increase in neurotransmitter release
2) decrease or increase in receptor sensitivity
3) decrease or increase in number of receptors |
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Term
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Definition
1) sensory memory
2) short-term memory
3) long term memory |
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Term
| sensory memory (description) |
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Definition
| short term retention of sensory input; information that is scanned, evaluated, and acted upon |
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Term
| how long does sensory memory last? |
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Definition
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Term
| how long does short term memory last? |
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Definition
| seconds to minutes to hours |
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Term
| sensory memory is _____ in nature |
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Definition
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Term
| shorter short term memory is _____ in nature |
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Definition
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Term
| longer short term memory is _____ in nature |
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Definition
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Term
| long term potentiation causes (3) |
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Definition
1)enhanced neurotransmitter release
2)enhanced receptor sensitivity
3)increased number of receptors |
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Term
| how long does long term memory last? |
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Definition
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Term
| long term memory is _____ in nature |
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Definition
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Term
| two types of long term memory |
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Definition
1) declarative/explicit
2) procedural/implicit |
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Term
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Definition
| retention of events, people, places, facts, etc |
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Term
| where is declarative memory stored? |
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Definition
| in various parts of the cerebellum |
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Term
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Definition
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Term
| where is procedural memory stored? |
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Definition
| in cerebrum and cerebellum |
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