SKIN STRUCTURE AND FUNCTIONS IN MAMMALES:
The body of Rabbit is covered by skin. It shows two layers,
a)Epidermis
b) Dermis.
Associated with skin are hair, claw and glands.
1. Epidermis : It is the upper part of the skin. It is divisible into two parts
a) Stratum comeum This layer is hard scale like, dead keratinized and flat. Keratin prevents the passage of water and solutes. This layer is cast off periodically. Below this layer transparent layer is present It is called stratum lucidum. In this layer - iucidin substance is seen When stratum comeum is removed this lucidum layer will become stratum comeum Below the stratum lucidum another layer is present. It is called stratum granulosum. It contains granular cells. Final layer of epidermis is stratum germinatum. It shows columnar cells. These cells can undergo division.
In the epidermis special pigment cells are present they are called chromatophore cells.
2. Dermis : It is present below the epidermis It is tough and flexible. It is made by connective tissue, unstrapped muscles blood capillaries, nerves and fat cells This part of the skin is in contact with nerve endings.
Glands : In the skin of Rabbit sweat or sudorif glands and sebaceous glands are present.
The sebaceous glands are sac like glands. They are branched. They secrete oily secretion which keeps the hair and skin water proof
The sweat glands are thin and long tubes. They arc coiled the sweat glands are found deep in the dermis. They open on the surface of the skin. These glands will secrete salty, watery solution from blood. It is excretory in function. This gland plays an important role in the regulation of body temperature.
Hair : It is epidermal in origin. It is seen only in mammals. It develops from the stratum germinatum. It has two parts root and shaft the hair is enclosed in a tube like hair follicle. At the base of the follicle dermal papilla is present. It is supplied with blood vessels.
The skin covers the body and protects the body organs
Skin Functions :
1) It covers the body parts,
2) Sweat glands are excretory and regulate the body temperature.
3) Skin works as tactile sense organ.
4) Sebaceous glands are modified into mammary glands which secrete milk for young ones.
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