A typical root can be classified into the following four regions:
1. The Root Cap:
The cap like structure that covers the apex of the root. One of the functions of this thimble-shaped mass of cells (parenchyma cells) is that covers and protects the growing root tip. In some plants Root Cap is large and obvious and in others it is almost indistinguishable.
2. Meristematic Zone or Zone of cell division:
The growing tip of the root just behind the root cap. Cells in the zone are composed of an apical meristem means the cells of Meristematic Zone are actively dividing and continuously increase in number.
3. Zone of elongation:
This region lies just above the meristematic zone. The zone of elongation merges with the apical meristem and extends about 1 centimeter or less from the tip of the root. The cells of this zone increase in size. This zone helps in the growth in length of the plant root.
4. Zone of cell differentiation:
(The region of cell maturation) This is a zone that lies above the zone of elongation. In this zone most of the cells mature or differentiate into different types. They form the tissues like the epidermis, cortex and vascular bundles. In this region a large numbers of root hairs are also present. The delicate protuberances develop from many of the epidermal cells. These root hairs (the protuberances) are responsible for absorbing water and minerals from the soil and adhere tightly to soil particles, besides greatly increasing the total absorptive surface of the root.