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Showing posts from May 23, 2011

Accessory Organs Of The Skin - - Lesson 245

In this post we would learn about ‘accessory organs of the skin’. Then in our mind one question may arise? What are the accessory organs of the skin? 1. Hair: A fiber of hair is composed or consisted of a tightly fused meshwork of horny cells filled with the hard protein also called keratin. The growth of hair is similar to the growth of the epidermal layer of the skin. Deep-lying cells in the hair root which produce horny cells that move upwards or to the top through the hair follicles (shafts or sacs that hold the hair fibers). At the root of the hair follicle, melanocytes are located and they support the melanin pigment for the horny cells of the hair fiber. Whenever the melanocytes stop producing melanin, hair turns gray. Out of the five million hairs on the body, about 100,000 are on the head. They grow about a half inch (1.3cm) a month, and cutting the hair has no effect on its rate of growth. 2. Nails: Nails are hard, the plates called keratin plates covering the dorsal