Electrical Synapses

Electrical Synapses - membrane-bound sacs called synaptic...

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Electrical Synapses: Bridge junctions that correspond to the gap junctions. They contain protein channels that interconnect the cytoplasm of adjacent neurons. Neurons are electrically coupled, and transmission across these synapses is very rapid.A key feature is that they provide a simple means of synchronizing the activity of all interconnected neurons. In adults, these synapses are found in regions of the brain responsible for certain stereotyped movements, such as jerky movement of the eyes. Electrical synapses are abundant in non-nervous tissues, such as cardiac and smooth muscle, where they allow sequential and rhythmic excitation. Chemical Synapses: Specialized for release and reception of chemical neurotransmitters. The neurotransmitters function to open or close ion channels that influence membrane permeability and membrane potential. A typical chemical synapse is made up of two parts: (I) a knoblike axonal terminal of the presynaptic neuron, containing many
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Unformatted text preview: membrane-bound sacs called synaptic vesicles containing neurotransmitter molecules. (2) a receptor region on the membrane of a dendrite or the cell body of the postsynaptic neuron, which bears neurotransmitter receptors. The presynaptic and postsynaptic membranes are separated by the synaptic cleft. Chemical synapses prevent a nerve impulse from being directly transmitted from one neuron to another. The transmission of nerve impulses along an axon is an electrical phenomenon. The transmission of signals across chemical synapses is a chemical event that depends on the release, diffusion, and receptor binding of neurotransmitter molecules and results in unidirectional communication. Depending on the types of neurotransmitters released and the receptor proteins to which they bind, the result may be either excitation or inhibition....
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This note was uploaded on 11/22/2011 for the course BSC BSC1085 taught by Professor Sharonsimpson during the Fall '10 term at Broward College.

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