The root hairs add a great amount of surface area to the root system of a vascular plant and allow for more diffusion of water into the plant's roots. They are derived from the epidermis of a plant root. They extend off the root in a lateral fashion and are one-cell thick. Because they are thin and hair-like, osmosis can readily occur between the environment and the roots. Once inside, conducting tissue called xylem can transport the water as well as minerals, upward to the stems and leaves. Root hairs are located in the region of maturation on a root.