Describe the internal structure of a monocot (Maize) root.

(D) The internal structure of a monocot root (e.g.,Maize) consists of the following layers:
$(1)$ Epidermis: The outermost layer,also known as epiblema or piliferous layer. It consists of thin-walled,compactly arranged parenchyma cells. Some cells extend to form unicellular root hairs,which absorb water and minerals from the soil.
$(2)$ Cortex: It consists of several layers of thin-walled parenchyma cells with intercellular spaces. The innermost layer of the cortex is the endodermis.
$(i)$ Endodermis: It is the innermost layer of the cortex,composed of barrel-shaped cells. These cells show characteristic thickenings of lignin and suberin on their radial and tangential walls,known as Casparian strips. Some thin-walled cells opposite to the protoxylem are called passage cells,which allow the movement of water.
$(3)$ Stele: The central part of the root,which includes the pericycle,vascular bundles,and pith.
$(i)$ Pericycle: $A$ single layer of thin-walled parenchyma cells located just inside the endodermis. It gives rise to lateral roots.
$(ii)$ Vascular Bundles: Monocot roots are polyarch,meaning they have many xylem and phloem bundles (usually more than $8$). The arrangement is radial,where xylem and phloem are located on different radii. Xylem development is exarch (protoxylem towards the periphery and metaxylem towards the center).
$(iii)$ Pith: The central part of the root is occupied by a large,well-developed pith consisting of parenchyma cells.