Biology / Unit 12 Bio 2855 short lesson, about 20 seconds
Autonomic Nervous System: Two-Synapse Relay
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The idea
The autonomic nervous system controls internal organs without conscious control, relaying signals through two synapses: a preganglionic neuron synapsing onto a postganglionic neuron reaching the target organ.
In practice
A preganglionic neuron often synapses onto multiple postganglionic neurons, amplifying one signal across many cells.
Where people slip
The sensory-somatic system uses only one synapse between the central nervous system and its target — this relay is distinctive.
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