Epidermal structure

Sangster AG, Hodson MJ, Parry DW, Rees JA. A developmental study of silicifi-cation in the trichomes and associated epidermal structures of the grass Phalaris canariensis L. Ann Bot 1983 52 171-197. 

In all mammals, hair develops as an epidermal structure from papillae deep in the skin and acquires characteristic patterns on the scalp, eyebrows, eyelashes, and elsewhere on the body. In humans, hair growth is continuous throughout fife (declining with advancing age), occurs in cyclic patterns, and... 

The outermost layer of the skin is the epidermis. The cells in this layer may be hard or comified. Some animals have specialized epidermal cells in the form of scales, feathers, and hair. Other epidermal growths include hooves, nails, claws, horns (not anders), and beaks. Epidermal cells of all kinds are molted or shed and renewed by the growth of new cells from below. Epidermal structures such as hair and feathers may be rooted in the underlying dermis and fatty layers (see Figure 6.3). 

Tezuka, T., Freedberg, I. M., Epidermal Structural Proteins. I. Isolation... 

Sebaceous gland Epidermal structure, associated with hair follicles, that secretes an oily substance called sebum. 

Sweat gland Epidermal structure that empties a watery secretion through pores in the skin. 

Hair is complex multicomponent fibre with both hydrophilic and hydrophobic properties. It consists of 65-95% by weight of protein and up to 32% water, lipids, pigments and trace elements. The proteins are made of structured hard a-keratin embedded in an amorphous, proteinaceous matrix. Human hair is a modified epidermal structure, originating from small sacs called follicles that are located at the... 

Zinc Content of Human Epidermal Structures (Eggleton ) (Parts per million of fat-free dry matter)... 

Sulplmr.—S, a.n. 16 a.w. 32 06. In plants, sulphur is universal and fairly uniformly distributed as proteins, organic sulphides, and inorganic sulphates. Values range from about O Ol to 0 2 per cent, of fresh material. In higher animals, the sulphur value depends largely on the amount of scleroprotein present. Thus, mammalian muscle has about 0 2 per cent, total sulphur skin, h, feathers, and other epidermal structures may have tip to ten times as much. The sulphur content of foods has been surveyed by Masters and McCance (1939). 

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