part_of part of part of contained in existence overlaps material entity anterior region of the whole animal dorsal region of the whole animal posterior region of the whole animal ventral region of the whole animal juvenile stage head region prepharyngeal region parapharyngeal region tail region neuropil neuron associated cell (sensu Nematoda and Protostomia) adult hermaphrodite asexual adult copulatory region glial cell PMID:29674431 PMID:29674432 glia PMID:27612384 PMID:27612382 PMID:28137894 glia cell PMID:30471994 CL:0000125 https://orcid.org/0000-0003-2569-1939 | https://orcid.org/0000-0002-7535-4407 Planarian_Anatomy A non-neuronal cell of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, guide neuronal migration during development, and exchange metabolites with neurons.