Question

Hard epidermal covering rhamphotheca is often traced in-------- of a bird.

Answer 1

The walls of the epidermal cells of the above-ground parts of plants contain cutting and are covered with a cuticle. The cuticle reduces water loss to the atmosphere. It's sometimes covered with wax in smooth sheets, granules, plates, tubes, or filaments.

Complete answer:
In the birds, there's an outer covering or horny sheath present on their beak which is understood as rhamphotheca. These are often further divided into rhinotheca and gnathotheca. Rhinotheca is the covering present on the upper mandible and gnathotheca is present on the lower mandible.

This covering originates from the Malpighian cells of the epidermis of birds and grows from plates at the bottom of every mandible. So, hard epidermal covering rhamphotheca is often traced in the 'Beak' of a bird.

Heavily cornified epidermis covers the beak, claws, spurs, and therefore the scales on the legs and feet. These structures (except the rear of the leg and underside of the foot) contain beta-keratin like that in reptilian scales. Most birds have sebaceous secretory glands at the bottom of the tail and within the ear canals.

Therefore the correct answer is ‘Beak’.

Note: A bird's beak may be a unique and multi-functional tool. It can help a bird gather or capture food, communicate, groom feathers, defend territories, and attack rivals. the form of a bird's beak may be a clue to its main source of food. The bird's beak sign of the esophagus is employed to ask the tapering of the inferior esophagus in achalasia.