Question

Epiblema is the name of
(a) Epidermis of leaf
(b) Epidermis of stem
(c) Epidermis of dicot root
(d) Epidermis of both dicot and monocot roots.

Answer 1

Hint: This layer provides a barrier to infection from environmental pathogens and regulates the quantity of water released from the body into the atmosphere through transepidermal water loss.

Complete step by step answer:
Epidermis with root hairs is called epiblema or piliferous layer or rhizodermis. It is found in the root hair region of the root. Root hairs are small, tubular, unicellular, epidermal outgrowths. It takes part in the absorption of water and minerals.
- The epidermis has no blood supply and depends on diffusion from the dermal cells for all its metabolic needs.
- The dead- cell layer of the stratum corneum protects from a water loss that allows the vertebrates to dwell on land.
- Keratin, produced in migrating epidermal cells, forms the basis of nails in our fingers, feathers, and beaks of birds and other epidermal derivatives.
- The epidermis is thickest on the friction surfaces and thinnest over the eyelids, on the lower parts of the abdomen, and around the external genitalia.
- The epidermis consists of a living malpighian layer, in contact with the basement membrane (which is attached to the dermis) , and a superficial horny layer of dead cells. The malpighian layer consists of both the stratum basale and the stratum spinosum of the epidermis layer.
So, the correct answer is, ‘(d) Epidermis of both dicot and monocot roots.’

Note: The epidermal cells, which multiply chiefly at the base in contact with the dermis, gradually ascend to the surface, manufacturing keratin as they go and finally die in the upper part, forming a horny layer.