Changes

*'''Sebaceous Glands'''

*'''Sebaceous Glands'''

One or more sebaceous glands surround each '''hair follicle''' at a point about 1/3 of its length from the surface.  Each gland is composed of numerous ''acini'' attached to a common '''excretory duct''' through which they discharge their secretions onto the hair shaft and epidermis.  In the skin and eyelids such glands release the cell contents together with secretory products with holocrine secretion.  This secretion involves '''apoptosis''' in which the secretory products and cell debris are released into the gland lumen.  The secretory products vary from species to species and include various fatty acids, diglycerides, cholesterol, diesters, wax esters and giant-ring lactones.

One or more sebaceous glands surround each '''hair follicle''' at a point about 1/3 of its length from the surface.  Each gland is composed of numerous ''acini'' attached to a common '''excretory duct''' through which they discharge their secretions onto the hair shaft and epidermis.  In the skin and eyelids such glands release the cell contents together with secretory products with holocrine secretion.  This secretion involves [[General Pathology - Necrosis#Apoptosis|apoptosis]] in which the secretory products and cell debris are released into the gland lumen.  The secretory products vary from species to species and include various fatty acids, diglycerides, cholesterol, diesters, wax esters and giant-ring lactones.

The function of sebum is that of an emolient of the hair and skin, preventing excessive dryness.  It may combine with '''sweat''' to form an emulsion within the stratum corneum and a form of cement around the hair pores preventing bacterial invasion of the epidermis.

The function of sebum is that of an emolient of the hair and skin, preventing excessive dryness.  It may combine with '''sweat''' to form an emulsion within the stratum corneum and a form of cement around the hair pores preventing bacterial invasion of the epidermis.