Hair Essay, Research Paper
Hair grows all over the human body. Hair is produced by hair follicles. Hair follicles are indentations of the epidermis or the outer skin layer. The epidermis contains many important things that have to do with hair. It contains the hair root and the muscle attached to it. It also contains the sebaceous or oil, glands.
Hair is made up of dead skin cells. The dead skin cells gather in the epidermis. The dead skin cells are filled with protein, most of which is known as keratins. Because of this keratins are the most valuable protein to hair.
The dead skin cells contained with keratin protein then are woven together like a rope, which forms the hair fiber. When hair fiber is woven different ways it forms different hair like curly and straight hair. This is all happening in the epidermis. The hair fiber is what you can see on the outside of your body. Hair fiber is woven together many different ways. This makes every ones hair different. The hair fiber in fact has three different layers to it. The first outer most layer is know as the outer cuticle. The outer cuticle has a fish scale like structure. The next layer down is known as the cortex. The cortex contains the bulk of the fiber. The last and innermost layer of hair fiber is known as the medulla. The medulla in fact allows the hair fiber to stretch and move. If the hair fiber is unhealthy or damaged the medulla will not allow the hair fiber to stretch as much as it is suppose to.
Hair color is determined by melanocytes. Melanocytes are cells that produce pigment that gives the hair color. Every ones pigment is different; therefore, no two hairs are exactly the same color. Over time the pigment cells that produce the hair color stop producing pigment. This usually happens to adults between the ages of 30 to 50 years of age. When the pigment is not being produced anymore the hair turns to a gray like color. Once the pigment has stopped it will never start again.
It may seem as though you hair is growing all of the time, but in fact it is not. Hair goes through two different phases. The phases are the active phase and the rest phase. The active phase is when the hair is actually growing. This is known as the anagen phase. The anagen phase lasts approximately two to six years. At any given time approximately 90 percent of the scalp hair is in this stage. During this time the hair is growing at a steady rate. A hair in the anagen or active phase grows approximately 6 inches o a white female. Other cultures have different growing rates.
The other phase that hair goes though is known as the telogen phase. During the telogen phase the hair is almost like resting, it doesn?t grow. After the phase is over the hair falls out. In the hairs place a new hair will start to grow and start the two phases all over again. At any given time during this phase approximately 10 percent of hairs are going though the telogen phase.
As a result, it?s considered normal to lose from twenty to one hundred hair every single day. The only thing that is considered abnormal is when there is a change in your regular pattern of hair loss. Also the pattern can change due to genetic factors, extreme dieting, and extreme stress. Mostly thought patterns change though medications.