what does upper epidermis mean
7. epidermis. The epidermis cells (from the Greek ÎµÏÎ¯Î´ÎµÏÎ¼Î¯Î´Î±, meaning over-skin) is a single-layer of cells that covers the leaves, flowers, roots and stems of plants.It forms a boundary between the plant and the external environment.. epidermis. The epidermis cells (from the Greek ÎµÏÎ¯Î´ÎµÏÎ¼Î¯Î´Î±, meaning over-skin) is a single-layer of cells that covers the leaves, flowers, roots and stems of plants.