Hair into the hair shaft and hair root of two parts.
hair shaft is exposed outside the skin part, that the visible part of hair from the keratinized cells. Organizations can be divided into epidermis,
authentic coach handbags, cortex and hair pulp layers. Containing melanin from the hair shaft composed of elongated cells, the cytoplasm containing melanin granules, melanin to hair color rendering. The number and melanin content of hair color related.
hair root is the part buried in the skin, is the root of the hair. Hair root length in the skin can not see, and is surrounded by hair follicles. Hair follicle is composed of epithelial tissue and connective tissue sheath capsule was formed by the epidermal growth down the cystic structure, the outside coated with a layer of skin evolved from the fibrous sheath. The end of the hair root and hair follicle enlargement, said the hair bulb. Active hair bulb cell division, is the hair growing point. Hair bulb at the bottom of depression, which broke into the connective tissue to form a dermal papilla. Dermal papilla contains capillaries and nerve endings, can nutrition hair bulb, and sensory function. If the atrophy or destruction of dermal papilla, hair stop growing and fall off gradually by
. There are a bunch of hair follicles on one side of the oblique muscle,
coach leather handbag, known as the standing hair muscle. Legislative hair follicle muscles in the lower end with the other end in the shallow dermis, muscle contraction when standing hair, the hair can be erected. Some small blood vessels distributed through the dermis to the hair bulb, the supply of its role as part of the hair bulb of hair growth and nutrition.
different with age, will change the nature of hair, same hair follicles to grow hair is not the same. During puberty, axillary and pubic area president of the bristles of the pubic hair, armpit hair instead of vellus hair; to old age, scalp hair follicles tend to return to vellus hair to men's most famous, the same situation found in the armpits and pubic Ministry to women than the.
hair growth rate is inconsistent, mainly related to the following factors:
(1) part of the fastest hair growth, daily growth of 0.27 ~ 0.4mm, armpit hair grow every day 0.21 ~ 0.38mm,
cheap replica coach bags, click here calculation, the hair length of about 1cm a month or so, another day of chin hair grow 0.21 ~ 0.38mm, other parts of about 0.2 mm.
(2) the growth rate of ######: Hair Women
(3) the hair at the age of 15 to 30 years old, the most vigorous growth, slow hair growth elderly, gender differences disappear.
(4) growing faster than the winter season, summer.
(5) day and night than during the day and night growing fast.
(6) with the body parallel relationship between health status.
(7) and proportional to the thickness of the hair follicle and hair growth compared to a year under normal circumstances, hair loss of about 70g, while the daily shedding of hair is generally not more than 100.
hair growth and replacement have certain laws, not continuous, but cyclical. Generally be divided into three stages, namely growth phase, telogen, and off period.
addition of ###### hormones also affect the speed of hair growth. The most vigorous ###### hormone secretion during pregnancy, increasing the life of the hair; and post-production, ###### hormone restore the original number of hair growth to resume normal speed, then the hair will be a substantial fall.
features a lot of hair, it helps regulate body temperature, but also the tactile organ, when we touch the body surface, the roots of the hair will have a slight movement; This action will immediately around the hair shaft small branches of the nerve around the intercepted material, and then transmitted to the brain via sensory nerves to go. Each hair is attached to one or several secreted by the tube arranged in the sebaceous glands composed of acini.
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