Here is your brief note on Hairs

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Hairs are epidermal structures, which are found in the mammals. Each hair develops as a thickening of the stratum germination, of the epidermis and is distinguished in to two parts, the basal part, laying in the dermis is called root and the upper part traversing the dermis and projecting from the epidermis is called shaft.

Hair is enclosed into a tube like invagination of the epidermis formed by stratum Malpighi. It is called the hair follicle, situated at the base of each hair follicle is a dermal tissue, which forms a small protuberance, called hair papillae, which is reach in nerves and blood vessel.

The epidermic cells situated above the hair papillae multiply and are responsible for the growth of the hair. The shaft of the hair is covered by a cuticle. With in the cuticle is situated a layer, fibrous or cortex made up of elongated horney epidermal cells, while in the centre lies the medulla or pith consisting of rounded cells.

The hair follicles lie somewhat slantingly in the skin and to one side of each is attached a small rector muscle, which is responsible for raising the hair in cold fear and anger.


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