develops from composed primarily of immediate transformation of produces glial cell spondin-1 cell layer neural tube notochord floor plate FP AAO:0011041 ZFA:0000022 The specialized glial structure (non-neuronal cells) situated at the ventral midline of the embryonic neural tube; this structure spans the anteroposterior axis from the midbrain to the tail regions, separating the left and right basal plates of the developing neural tube, and serves as an organizer to ventralize tissues in the embryo as well as to guide neuronal positioning and differentiation along the dorsoventral axis of the neural tube. EFO:0003473 TAO:0000022 BTO:0001720 ventral plate UBERON:0003079 bodenplatte Wikipedia:Floor_plate RETIRED_EHDAA2:0000545 EMAPA:32684 floorplate ectoderm-derived structure embryonic tissue presumptive floor plate