Concept explainers
To discuss:
Three ways in which synaptic transmission is ended.
Introduction:
Turning off the stimulus on time is as important as stimulating a postsynaptic cell, or else the post synaptic neuron will fire indefinitely, leading to a physiological coordination breakdown. The neurotransmitter molecule binds to the receptor for just 1 ms or so, then it dissociates from the receptor. If a presynaptic cell releases the neurotransmitter continuously, one molecule is rapidly replaced by another neurotransmitter molecule and the postsynaptic neuron is re-stimulated. This is one of the ways of stopping synaptic transmission - this terminates the addition of a new neurotransmitter molecule and getting rid of which is there already. The first step is attained by a signal cessation in the presynaptic neuron. The second step is achieved by three modes that are explained below.
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Anatomy and Physiology
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