Question

What is the name of the extensions of the epidermal cells of a root which help in respiration?

Answer 1

Hint: The epidermal cells are the types of cells that form the epidermis of the plants including the roots. Their main role is the protection of the internal tissues from harmful environmental factors, microbes and also UV light. The cells also help in gaseous exchange. In the roots, the epidermal cells are extended to form a structure that helps in the uptake of minerals and nutrients.

Complete answer:
The epidermis is the outer layer of the plant which acts as a barrier between the plant and the external environment. It is present in almost all the parts of the plant including leaves, flowers, stem and roots. The main function of this layer is protection, preventing water loss, gaseous exchange, secrete several metabolites etc.

Cellular structure: The epidermis is made up of a single type of cell. These cells are numerous and are less specialised. The elongated shaped cells are present in the epidermis of the leaf. The epidermis is made up of several layers of cells which do not have intercellular space. This helps in providing strength to the plants. In the case of roots, the epidermis forms fine projections called root hairs. They increase the surface area for the absorption of maximum nutrients and water. The root hairs help in gaseous exchange or respiration.

So, we can conclude that the root hairs are the extensions of the epidermis in the root.

Note: The epidermis of the plants differentiates to form stomata. They are the fine openings present at the bottom surface of the leaves which are guarded by the guard cells. The guard cells regulate the opening and closing of stomata.