The root is the part of the plant that remains inside the ground and anchors the plant while beneath the soil. It is the descending part of the plant. The primary function of the root is to absorb water and minerals from the soil. The water and minerals are conducted to different parts of the plant through the xylem. It is the non-green part of the plant and does not bear nodes, internodes, leaves or buds. Roots can be of mainly two types – taproot and fibrous root. 

Functions of Root

Absorption of water and mineral salts from the soil is carried out by the root.The root conducts the absorbed water and mineral salts from the root hairs to theFood materials are stored in the roots of many plants,

Regions of the root 

There are four main regions present in the root: the region of maturation, the region of elongation, the region of cell division and the root cap. 

The region of maturation

• The major part of the root is occupied by the region of maturation.
• The cells of this region attain maturity and differentiate into tissues.
• It comprises several root hairs that help in the absorption of water and nutrients from the soil.
• The primary function of the region of maturation is to transport water and nutrients upwards in the shoot system. It also causes secondary growth in the roots of dicot plants. It also helps in producing lateral roots.

The region of elongation 

• It lies above the region of meristematic activity and below the region of maturation.
• It comprises the newly formed cells. These cells lose the power of division, so they contribute to elongation.
• Its function is to help in increasing the length of the root; hence it is named the region of elongation. The outer cells of the zone of elongation help in absorbing water and minerals from the soil.

The region of cell division 

• The region of cell division is also known as the region of meristematic cells.
• This layer lies below the region of elongation and above the root cap.
• The cells of this region divide continuously.
• The cells present in the region of cell division have dense protoplasm and thin cell walls.
• It comprises three layers – dermatogen, periblem and plerome. 
• The cells of the dermatogen give rise to the root cap. The cells of the periblem give rise to the cortex, and the cells of the plerome give rise to stele.
• The region of cell division helps in increasing the number of cells in the root.

The root cap

The root cap is also known as calyptra. The root cap acts as the covering of the apical part of the root. The apical meristem produces the root cap. The Latin meaning of the root cap is the head of the root. In some species, it is present in multiple numbers, while in some other species (especially aquatic plants), root caps are absent. Root pockets are present instead of root caps. 

Shape and structure of the root cap

• It is a cap-like structure present on the growing root tip.
• It protects the apex of the root.
• It is a multilayer dome-shaped structure. 
• It is present in the roots of almost all crop plants.
• It represents the region that faces potential damage and friction from the particles present in the soil.

Functions of the root cap

• The main function of the root cap is to enable the growth of the root downward (with gravity). It enables geo perception or gravitropism. 
• It also allows the shoot system of the plant to grow upward (against gravity).
• The root cap helps in protecting the root meristem. 
• The plants in which root packets are present (in aquatic plants) help in maintaining the balance.
• It helps the tender root to penetrate deep into the soil by secreting mucilage. Mucilage acts as a lubricant that helps the root in making its way through the soil.
• It also helps in establishing a communication with the microorganisms present in the soil.

Conclusion

The root is the underground part of the plant that helps in the absorption of water, nutrients and minerals from the soil. Four main regions are present in the root: the region of maturation, the region of elongation, the region of cell division and the root cap. The root cap is also known as calyptra. It acts as the covering of the apical part of the root. The root cap is produced by the apical meristem and is a multilayer cup-shaped structure present in the roots of almost all crop plants. It represents the region that faces potential damage and friction from the particles present in the soil. The main function of the root cap is to enable the downward growth of the root (with gravity).