About Hair
Hair grows from the skin as the rods horns and spread almost all over the body and head. The point is to protect against changes in the weather, tetapikini particularly useful as an ornamental. Meskipunwujud hair in a variety of different places, but basically the same arrangement of all types of hair. The only difference lies in the way the growth of the thickness and depth of intellect.
Various kinds of hair:
- Long hair: in the head, beard, armpits, genitals, upper lip.- Hair is stiff: eyebrows, eyelashes, nostrils.- Fur roma (lanugo, vellus hair): fine hair on the face and body; not bersumsum and not pigmented.
Development and the hair cycle
Hair began to take shape before the third month of fetal development (fetus) as a protrusion-protrusion basale corneum into the epidermis. Thus was formed the beginning of the content of the hair. The lower end of the shoot was going to include a lump, which occurs on connective tissue, blood vessels and nerve fibers. Clumps of hair is known as papillae. Because this part melabar and called the hair bulb. The cells of the hair bulb gets nourishment from hair papillae and will hold a mitotic division, multiply and pushed towards the surface of the skin to form the beginning of the hair (lanugo) that grows at an angle into an arid skin will then penetrate. The first hairs (lanugo, vellus hair) will fall towards the unity or the second year, followed by growth of hair remains. Determine the direction of hair growth in hair fall.
Hair grows through the cycle that includes three phases of growth:
1. The period of anagen: hair grows because of the proliferation of cells in mitosis hair bulbs, the length of over 1,000 days.2. The katagen: membranes and connective tissue around the bladder hair in the hair bulb thickened, papil mengeriput hair, so the hair bulbs are no longer obtain food. Because so the hair does not grow again, the deepest part of the hair rounded as a bludgeon. Emikian hair called "clubbed hair". clubbed hair does not immediately fall, because the hair is still set in the womb by a rounded edges are widened. Gradually, the hair thus pushed up and eventually fall out. The length of this period of approximately 14-21 days.3. The period of telogen: Hair papil wrinkled during katagen will grow back. Bulbs newly formed hair around the hair papillae and the new hair grows under '' clubbed hair '', which is then pushed out. This long period is approximately 100 days.
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