(a)Meristematic cells near root tip The cells of this region are called Root Apical Meristems (RAM) and are in active state of division thus their number increases continuously. The cells of this region are thin walled with dense cytoplasm and large nucleus. They have the abilliy to divide and self perpetuate.
(b) The Cells in the Elongation Zone of the Root This region is situated just above the meristematic zone. In the cells of this zone, a large number of small vacuoles develop and later these vacuoles fuse to form one large cental vacuole filled with cell sap. The ells are elongated in this region