TLDR Hair grows from living roots, is made of dead keratin, and goes through growth, rest, and shedding stages.
The chapter described the structure and growth cycle of hair, noting that individual hairs have living roots in the scalp and undergo various stages of growth, rest, and shedding. The hair shaft, which is the visible part, is dead and composed of keratin, a strong and flexible protein. Hair is elastic, porous, and capable of absorbing moisture, with uncut hair having a pointed end.
55 citations
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January 2013 in “International Journal of Cosmetic Science” African hair's keratin structure is influenced by its higher lipid content.
52 citations
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April 2012 in “Journal of Investigative Dermatology” KRTAP2 genes are crucial for hair structure and may impact hair disorders and treatments.
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August 2006 in “Biopolymers” Researchers extracted tiny keratin filaments from human hair by unzipping its outer layer.
71 citations
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August 2005 in “The journal of investigative dermatology. Symposium proceedings/The Journal of investigative dermatology symposium proceedings” Hair keratin-associated proteins are essential for strong hair, with over 80 genes showing specific patterns and variations among people.
34 citations
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August 2003 in “Clinical and Experimental Dermatology” Pregnant women's hair gets thicker.
