Question

What is the function of root hair?

Answer 1

A root hair is formed from the trichoblast cell present in the epidermis of plant roots. These are lateral single-cell extensions that are very thin and rarely branched. Root hair cells have a large surface area and they aid in the functioning of the roots.

Complete answer: Roots are the underground part of the plant. They are one of the major parts of a plant. They function to absorb and provide water and minerals from the soil throughout the plant. The roots perform osmosis through which water from soil diffuses towards the plants. The transpirational pull aids in water conduction from the roots.
The roots are cylindrical thin structures that can be branched or singular. The outer layer of roots is made of the epidermis. The epidermis consists of trichoblast. The trichoblasts are root hair forming cells. Root hair cells are longitudinal extensions that arise from the epidermis and extend longitudinally in the soil. The root hairs are rarely branched. These can be seen with naked eyes or sometimes these are microscopic. The root hair cells have a larger surface area which facilitates a faster osmosis rate. The root hair cells are the main absorbing units of a root. They are found in the regions of maturation of root. Also, the root hair cells can penetrate deep in the soil particles they prevent the attack from harmful bacteria from entering the plant. Root hair cells also help in establishing beneficial relations with good microbes. These are generally nitrogen-fixing bacteria that live in association with these cells.

Note: In the leguminous plants that bear root nodules the root hair cells inhibit nitrogen-fixing bacteria in them. This results in a beneficial symbiotic relationship. The fixed nitrogen is converted into ammonium which is taken up by the rest of the plant. Thus, root hair cells are very important in plant development.