News tagged with hair

Related topics: stem cells

Mapping the skin in time and space

The skin is the largest organ in mammals and it serves to protect the body from outside influences, such as physical damage, radiation, fluid loss or extreme temperatures. To fulfill this function, a plethora of cell types ...

Oct 04, 2016
popularity0 comments 0

Daily baths not a must for kids

(HealthDay)—Here's welcome news for parents tired of forcing their kids to take a daily bath: Children may not need to bathe every day after all.

Sep 22, 2016
popularity8 comments 0

Detecting hearing loss, vertigo via blood tests

There are more than 30 blood tests in clinical practice today to confirm disease. For heart attacks, cardiologists test the blood for cardiac enzymes; for osteoporosis, proteins in the blood can signal thinning bones.

Aug 18, 2016
popularity7 comments 0


Hair 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.

This text uses material from Wikipedia, licensed under CC BY-SA

Subscribe to rss feed