What are the growth regions of roots?

The Meristematic Region or Growing Point

This region occurs immediately behind the root cap. The Meristematic region consists of meristematic tissue and is protected by the root cap. The cells are very activeand divide rapidly to form new cells which differentiate later to form more specialized root tissues. The cells of this region also replace the cells rubbed-off from the root cap and provide additional cells for the next region.

Function

• This is the region where the cells divide and where additional cells are provided for the zone of elongation.

The Region of Elongation

The cells formed in the meristematic region undergo rapid growth in length. This causes the root to elongate and penetrate deeper into the soil in search for water and mineral salts. The meristematic and elongation zones are also referred to as the region of growth.

Function

• In this region the cells undergo rapid enlargement,i.e. the cells undergo rapid growth in length.

The Root-hair Region

The root hair region occurs a short distance above the region of elongation. Here a large number of fine, hair-like outgrowths are formed. The root hairs arise from the epidermal tissue of the root and are called root hairs. The root hairs are short and short-lived and develop on theprimary and secondary roots. A root-hair consists of the following parts: a thin cell wall, a thin lining of cytoplasm which contains thenucleus and a comparatively large vacuole containing cell sap.

Function

• The main function of the root hairs is to increase the area of absorption of the root.

The Mature Region

The mature region is situated above the root hair region. Here the root becomes thicker and secondary or lateral rootsare developed. The secondary roots in turn rebranch to form tertiary roots. Each lateral branch has its own cap, root hairs, meristematic, elongation and mature regions. The roots in this region are covered by a protective cork layer .

Functions

• In this region the cells undergo differentiation into specialized cells,(e.g. xylem and phloem).
• It also serves to anchor the plant.

febbie