The segmental ganglia (singular: s. ganglion) are
ganglia
A ganglion (: ganglia) is a group of neuron cell bodies in the peripheral nervous system. In the somatic nervous system, this includes dorsal root ganglia and trigeminal ganglia among a few others. In the autonomic nervous system, there a ...
of the
annelid and
arthropod central nervous system that lie in the segmented
ventral nerve cord
The ventral nerve cord is a major structure of the invertebrate central nervous system. It is the functional equivalent of the vertebrate spinal cord. The ventral nerve cord coordinates neural signaling from the brain to the body and vice ve ...
. The ventral nerve cord itself is a chain of
metamerism ganglia, some compressed.
References
Animal nervous system
Arthropod anatomy
Annelid anatomy
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