part_of part of part of root cortex hypodermis exodermis The sub-epidermal layer or layers of cells of the root similar in structure and cytochemical characteristics of the endodermis, the outermost layer or layers of cells of the cortex. plant_anatomy PO:0005772 exodermis (Spanish, exact) 外皮 (Japanese, exact) root hypodermis (related) The cell walls are thickened and contain suberin. Absent in pteridophytes, fibrous in Phoenix and accompanied by sclerenchyma in Ananas.