The mature region is situated above the root-hair region. Here the root becomes thicker and secondary or lateral roots (secondary root, lateral root) are developed. The secondary roots in turn rebranch to form tertiary roots. Each lateral branch has its own root cap, root hairs (root hair), meristmatic region, elongation region (region of elongation) and mature region. The roots in this region are covered by a protective cork layer. In this region the cells undergo differentiation into specialised cells and it also serves to anchor (anchorage) the plant.