Term
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Definition
| a junction that mediates from one neuron to another neuron or to an effector cell. |
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Term
| what conducts impulses toward the synapse and trasmits impulses from the synapse? |
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Definition
| the presynaptic neuron conducts impulses and post synaptic impulses transmits impulses |
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Term
| what types of axons are there, explain. |
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Definition
| axodentric - synapses between the axon of a neuron and a dendrite of another. axosomatic - synapse of one axon and the soma of another. other types of axoaxonic - aaxon to axon . dendrodendritic - dendrite to dendrite. dendrosomatic - dendrite to soma |
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Term
| give me some general information about electrical synapses. |
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Definition
| electrical synapses are less comon then chemical synapses. they involved in memory and focus , emotions , ion and water homeostasis, arousal from sleep. it corresponds to gap junctions found in other cell types. |
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Term
| give me some general information about chemical synapses |
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Definition
| specialize for the release and reception of neurotransmitters. typically composed of two parts , axonal terminal of the presynaptic vessicles . and there is a receptor region on the dendrites or soma |
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Term
| give me some general info of the synaptic cleft |
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Definition
| fluid filled space seperating the presynatic and post synaptic neurons. prevents neurons from directly passing from one neuron to another. |
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Term
| give me some info about the transmission across the synaptic cleft. |
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Definition
| is a chemical event as opposed to an electrical one. ensures unidirectional communcation between neurons. |
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Term
| how does the information transfer work of the synaptic cleft? |
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Definition
| 1. an electrical impulse reachs the axonal terminal to release ca2 channels. 2. neurotransmitters are released through exocytosis. 3. the neurotransmitter crosses the synaptic cleft and binds to the receptor sites in the post synaptic neuron. 4. this causes permeability changes in the post synaptic neuron that causes it to excite or inhibit |
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Term
| what happens when a neurotransmitter bounds to a post synaptic neuron |
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Definition
| when neurotransmitter bound with the post synaptic neuron..produces a continuous postsynaptic effect. blocks reception of additional messages and must be removed from its receptors. |
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Term
| removal of neurotranssmiters occur when they |
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Definition
| are degraded by enzymes or when . reabsorrbed by astrocytes or presynaptic terminals. |
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Term
| what is the synaptic delay? |
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Definition
| neurotransmitters must be released , diffuse across the synapse and bind to its receptors. it takes 0.3 to 5.0ms. its the rate limiting step of neural transmission. |
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Term
| POST SYNAPTIC POTENTIALS ( Neurotransmitter receptor mediate changes in membrane potential according to |
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Definition
| how long the neurotrasnmitters are bound to the receptors and how much neurotransmitters are released |
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Term
| what are the two types of post synaptic potentials? |
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Definition
| ESPS and ISPS ...excitatory post synaptic potentials and inhibitory post synaptic potentials |
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Term
| whats the difference between ESPS and ISPS |
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Definition
| excitatory post synaptic potentials are graded potentials that occur in the axon. they use only chemically gated chanels. Na and K flow in opposite directions. Inhibitory post synaptic potentials reduce the neurons ability for action potential. causes membrane to be more permeable to potassium and chloride. leaves the charge on the inner side negative |
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