Hair
hideHair is a protein filament that grows through the epidermis from follicles deep within the dermis. The fine, soft hair found on many nonhuman mammals is typically called fur; wool is the characteristically curly hair found on sheep and goats. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class. Although other non-mammals, especially insects, show filamentous outgrowths, these are not considered "hair" in the scientific sense. So-called "hairs" (trichomes) are also found on plants. The projections on arthropods such as insects and spiders are actually insect bristles, composed of a polysaccharide called chitin. There are varieties of cats, dogs, and mice bred to have little or no visible fur. In some species, hair is absent at certain stages of life. The main component of hair fiber is keratin.
The hair can be divided into three parts length-wise, (1) the bulb, a swelling at the base which originates from the dermis, (2) the root, which is the hair lying beneath the skin surface, and (3) the shaft, which is the hair above the skin surface. In cross-section, there are also three parts, (1) the medulla, an area in the core which contains loose cells and airspaces (2) the cortex, which contains densely packed keratin and (3) the cuticle, which is a single layer of cells arranged like roof shingles.
For more information about Hair, read the full article at
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News tagged with hair
Single gene may cause curly hair
Nov 10, 2009 |
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(PhysOrg.com) -- Scientists in Australia have identified a single gene that strongly influences whether you have curly or straight hair.
Ion channel turns ear on its head
Medicine & Health / Neuroscience
Apr 23, 2009 |
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Scientists thought they had a good model to explain how the inner ear translates vibrations in the air into sounds heard by the brain. Now, based on new research from the Stanford University School of Medicine, it looks like ...
Power steering for your hearing: Ears have tiny 'flexoelectric' motors to amplify sound
Apr 22, 2009 |
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Utah and Texas researchers have learned how quiet sounds are magnified by bundles of tiny, hair-like tubes atop "hair cells" in the ear: when the tubes dance back and forth, they act as "flexoelectric motors" ...
Diet secrets of 'the Royals' -- Elephant tail hair isotopes show cattle out-munch pachyderms
Apr 13, 2009 |
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Two weeks after the rains begin, an elephant family named "the Royals" usually switches to a grass diet to bulk up for pregnancy and birth. But when they wandered off their African reserve one rainy season, ...
Researchers Develop Flow Sensors Based on Blind Fish Hair Structures
Mar 24, 2009 |
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(PhysOrg.com) -- A blind fish that has evolved a unique technique for sensing motion may inspire a new generation of sensors that perform better than current active sonar.
No longer a gray area: Our hair bleaches itself as we grow older
Biology /
Feb 23, 2009 |
4.6 / 5 (25) |
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Wash away your gray? Maybe. A team of European scientists have finally solved a mystery that has perplexed humans throughout the ages: why we turn gray. Despite the notion that gray hair is a sign of wisdom, these researchers ...
Hair of Tasmanian Tiger Yields Genes of Extinct Species
Biology /
Jan 12, 2009 |
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All the genes that the exotic Tasmanian Tiger inherited only from its mother will be revealed by an international team of scientists in a research paper to be published on 13 January 2009 in the online edition ...
Studying hair of ancient Peruvians answers questions about stress
Other Sciences / Archaeology & Fossils
Dec 09, 2009 |
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(PhysOrg.com) -- Recent studies show that one in three Canadians suffer from stress and the number is on the rise. But stress isn't a new problem.
Now hear this: Mouse study sheds light on hearing loss in older adults
Nov 09, 2009 |
5 / 5 (1) |
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(PhysOrg.com) -- Becoming "hard of hearing" is a standard but unfortunate part of aging: A syndrome called age-related hearing loss affects about 40 percent of people over 65 in the United States, and will afflict an estimated ...
Color differences within and between species have common genetic origin
Oct 22, 2009 |
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(PhysOrg.com) -- Spend a little time people-watching at the beach and you're bound to notice differences in the amount, thickness and color of people's body hair. Then head to the zoo and compare people to chimps, our closest ...
Now hear this: Scientists show how tiny cells deliver big sound
Oct 22, 2009 |
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Deep in the ear, 95 percent of the cells that shuttle sound to the brain are big, boisterous neurons that, to date, have explained most of what scientists know about how hearing works. Whether a rare, whisper-small second ...
Fish Sense Other Fish Via Ripples
Oct 15, 2009 |
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Although humans experience their world through vision, touch and the other senses, many creatures gather information about their surroundings through unique sensory mechanisms that humans don’t have.
Analysis of Copernicus putative remains support identity
Jul 07, 2009 |
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Swedish and polish researchers now publish results from the analysis of the putative remains of Copernicus. A DNA-analysis of shed of hairs found in a book from Museum Gustavianum, Uppsala University, was ...
Link between light touch and Merkel cells solves 100-year mystery
Jun 18, 2009 |
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Light touch - the sense that lets musicians find the right notes on a keyboard, a seamstress revel in the feel of cool silk, the artisan feel a curve in material and the blind read Braille - truly depends on the activity ...
Stress makes your hair go gray
Jun 11, 2009 |
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Those pesky graying hairs that tend to crop up with age really are signs of stress, reveals a new report in the June 12 issue of Cell.
