secondary vascular tissue ray system 2012-02-01T11:01:35Z rwalls PO_GIT:444 放射状組織 (Japanese, exact) radial system (exact) PO:0025411 May include ray tracheids, as in Pinaceae and some Cupressaceae. A portion of secondary vascular tissue (PO:0025409) that has as part ray wood parenchyma (PO:0004534) and extends radially in the secondary xylem (PO:0005848) and secondary phloem (PO:0005848) of a plant axis (PO:0025004). horizontal system (exact) plant_anatomy ray (broad)