Meristematic activity.

A typical root possess the four parts or regions

$(i)$ Root Cap The root is covered at the apex by thimble like structure called root cap. It protects the tender apex of root as it makes its way through soil

$(ii)$ Region of Meristematic Activity Few millimeters above the root cap. The cells of this region are very small, thin walled and dense protoplasm. They divide repeatedly

$(iii)$ Region of Elongation The cells proximal to the meristematic zone undergoes the rapid elongation and enlargement and are responsible for growth of root in length

$(iv)$ Region of Maturation The cells of elongation zone gradually differentiate and mature. This zone lies just proximal to the region of elongation