Term
| The action potential depolarizes the membrane of the nerve terminal (terminal button) and activates this |
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Definition
| a voltage –gated Ca2+ channel |
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Term
| The action potential depolarizes the membrane of the nerve terminal (terminal button) and activates a voltage –gated Ca2+ channel. Elevated Ca2+ in the cytosol does this |
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Definition
| stimulates the release of a neurotransmitter |
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Term
| Elevated Ca2+ in the cytosol stimulates the release of a neurotransmitter that binds to a receptor that activates this |
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Definition
| a ligand=gated ion channel that can depolarize or hyperpolarize the post - synaptic cell membrane |
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Term
| Vesicles accumulate neurotransmitter via this |
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Definition
| specific transport proteins and may require a proton gradient |
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Term
| Vesicle attachment membrane proteins (VAMPs) allow this |
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Definition
| binding to docking sites on the membrane |
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Term
| Ca 2+ channel activation promotes this |
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Definition
| vesicle fusion and transmitter release |
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Term
| Vesicles are removed via endocytosis and neurotransmitter is taken up for repackaging into vesicles or degradation by theses |
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Definition
| enzymes in the presynaptic cell |
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Term
| “ionotropic” neurotransmittersdo this |
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Definition
| directly bind to and activate a “ligand gated” ion channel |
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Term
| This results in a rapid change in the voltage gradient across the post-synaptic cell membrane |
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Definition
| ionotropic neurotransporter binding to ligand gated ion channels |
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Term
| Acetylcholine (Ach) activates a channel that allows this to enter the cell causeing this |
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Definition
| Na+ to enter the cell, depolarizing it |
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Term
| gamma amino butyric acid (GABA) activates this type of channel causing this |
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Definition
| a Cl- channel that hyperpolarizes the post synaptic cell membrane |
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Term
| the nicotinic Ach receptor has which sub units? |
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Definition
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Term
| Ach binding causes this to happen to the nicotinic channel |
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Definition
| a conformational change that opens the channel |
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Term
GABAa receptors are Cl- channels
They produce IPSPs and are targets
for |
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Definition
a variety of mood stabilizing and
sedative drugs, and also alcohol |
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Term
| this is a common excitetory neurotransmitter |
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Definition
|
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Term
| this is a common inhibitory neurotransmitter |
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Definition
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Term
| it takes this many synapses to produce a sufficient level of depolarization to activate voltage gated Na+ channels in the axon hillock and initiate an action potential. |
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Definition
| The combined activity of many synapses |
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Term
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Definition
| increasing the Na+ permeability causing a localized depolarization of the postsynaptic cell membrane |
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Term
| this type of summation requires multiple signals at the same time |
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Definition
|
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Term
| this type of summation requires multiple signals over the surface of the cell |
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Definition
|
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Term
| what is the threshold potential |
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Definition
| wth enough summations the minimum level of depolarization that will activate voltage gated channels |
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Term
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Definition
| an inhibitory neurotransmitter released from an inhibitory neuron increases Cl- permeability. |
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Term
| what does the increase on Cl permeability seen from IPSP's do? |
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Definition
| The negative charge offsets the EPSP so an action potential doesn’t occur |
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Term
| Acetylcholine is broken down by this enzyme in the post synaptic membrane |
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Definition
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Term
| this resynthesizes Ach after it is taken back up by the nerve terminal |
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Definition
| Choline acetyl transferase |
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Term
| neurotransmitters bind to a G-protein-coupled receptor which is this type of receptor |
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Definition
| (metabotropic receptors). |
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Term
| what two ways do G-protein coupled receptors (metabotropic receptors) work? |
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Definition
| directly activate an ion channel -or- the G protein may activate enzymes (e.g. adenyly cyclase) that produce second messengers (e.g. cyclic AMP) that activate protein |
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Term
| protein kinases created by activation of metabotropic receptors do this |
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Definition
| Protein kinases may activate or inhibit ion channels by phosphorylation. |
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Term
| what is the relative speed of the metabotropic receptors? |
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Definition
| the effects of metabotropic receptors take longer to develop and last longer |
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Term
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Definition
| Chemicals that bind to metabotropic receptors |
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Term
| two receptor types for acetocholine |
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Definition
| metabotropic(muscarinic) and ionotropic (nicitinic) |
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Term
| how can a neurotransmitter have different effects on different tissues? |
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Definition
| depending on the type of receptor it activates, nicitinic or muscarinic |
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