GapjunctFIG 7: Gap junctions function within and between layers to influence motor output.
Sense cells in head and tail synapse onto command interneurons of the ventral nerve cord, which in turn synapse onto motor neurons that make NMJs onto bodywall muscles. Cells are grouped by class into four layers (sensory/interneuron/motor neuron/muscle). Gap junctions occur selectively between these layers, but are more prominent within each layer. While most Gap junctions link homologous neurons (often bilateral pairs), there are cases where they link cells of opposing behaviors (PVC to AVA, A to B). Triangles represent sensory neurons, hexagons represent interneurons, circles represent motor neurons, and rhomboids represent bodywall muscles.
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