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Abstract
Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and fine vellus hair. Most common interest in hair is focused on hair growth, hair types, and hair care, but hair is also an important biomaterial primarily composed of protein, notably alpha-keratin. Attitudes towards different forms of hair, such as hairstyles and hair removal, vary widely across different cultures and historical periods, but it is often used to indicate a person's personal beliefs or social position, such as their age, sex, or religion. Human hair is a material considered useless in most societies and therefore is found in the municipal waste streams in almost all cities and towns of the world.
Key Words: Human Hair, Amino acids and Fertilizer
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Introduction:
1.1Discription: The word "hair" usually refers to two distinct structures:
1. The part beneath the skin, called the hair follicle, or, when pulled from the skin, the bulb. This organ is located in the dermis and maintains stem cells, which not only regrow the hair after it falls out, but also are recruited to regrow skin after a wound.
2. The shaft, which is the hard filamentous part that extends above the skin surface. A cross section of the hair shaft may be divided roughly into three zones.
The hair's structure can be divided into three distinct parts:
3. Medulla: innermost layer of the hair shaft composed of an amorphous, soft, oily substance.
4. Cuticle: thin protective outer layer that contains the nourishing portion essential to hair growth. It is highly keratinized, composed of cells shaped like scales that are layered one over the other, measuring about 60 micrometers long and about 6 micrometers wide.
5 Cortex: main component of the hair, containing long keratin chains that add elasticity, suppleness and resistance to the hair. The cells of the cortex are joined together by an intercellular cement rich in lipids and proteins. Each cell is composed of bundles that lie in the direction of the hair length: these are macro-fibrils which are made up of micro-fibrils, which in turn...