In plants, Dermal Tissue is the outer layer of plant cells. These cells typically harden and provide protection to the inner layer of cells, allowing the plant to survive animal movement and changing weather. Dermal tissue forms the Epidermis in plants, and can be softer or harder depending on the plant's function; ferns have a much softer epidermis than trees.
Vascular Tissue is found inside plants, and serves as the mechanism for water to be transferred from the roots to the leaves and other parts of the plant. Because vascular tissue is fragile, it is normally encased in a Dermal layer (see above). Vascular tissue is absorbent, allowing water to be "sucked" up the length of the plant where it is distributed to dehydrated tissues; as more water leaves the vascular system in the higher areas, more water is absorbed through the roots.