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Equine Integumentary System - Horse Anatomy (view source)
Revision as of 15:15, 19 November 2012
, 15:15, 19 November 2012→Hair
==Hair==
==Hair==
All hair has a similar structure: an outer cuticle, a cortex containing pigmentation, an inner medulla and a root or bulb from which the hair grows out of the follicle to form the shaft.
Each hair follicle has a sebaceous gland and an arrector pili muscle associated with it.
Hair follicles are divided into three parts:
:The ''infundibulum'' corresponds to the area from the opening of the sebaceous duct to the surface of the skin.
:The ''isthmus'' is the area between the opening of the sebaceous duct and the attachment of the arrector pili muscle.
:The ''inferior segment'' extends from the attachment of the arrector pili muscle to the dermal hair papilla.
The hair follicle originates from a peg of epidermal cells that grows down into the underlying dermis, where it forms a hair cone over a piece of dermis called the '''dermal papilla'''. The papilla provides the blood and nerve supply for the growing hair. From the hair cone, the cells keratinise and form a hair. As the hair grows up through the epidermis to the skin's surface, the cells at the point of the cone die, forming a channel, the hair follicle.
==Skin Glands==
==Skin Glands==
==Mammary Glands==
==Mammary Glands==
==Digit==
==Digit==