Hair Terminology
Human hair is growing in definite cycles. Below you can find out some information concerning three phases of hair growth.
Anagen is the phase of hair growth which is from 2 to 8 years long. During this period the cells in hair papillas divide themselves continually and this way they build the stalk of a hair. A stalk becomes hardened with keratine while gradual growing out of the cells into the skin pores. At the same time the cell is growing into deeper layers of skin to get nutrition.
Catagen is the next phase which is relatively short because it lasts for only 2 to 4 weeks and it the phase of a hair renewal. The hair follicle stops growing thus becomes degenerated but it does not fall out right away. It shrinks to around one sixth of its normal width. Its bottom part becomes destroyed and a hair papilla gets separated from its follicle. A hair bulb is separated from the blood nutrition and, as a result, the whole stalk becomes pulled outside when a hair follicle gets disintegrated.
Telogen is the last phase of a rest which lasts from 2 to 4 months. During this period a hair still is not growing, although it is detached to a follicle while its papilla is at rest. If the whole process (cycle) of hair growth is taking a normal course then app. 10 to 15% of hairs remain at this stage.
After the Telogen phase the whole cycle is completed and the Anagen phase begins. The new stalk of a hair is being formed and the old one id being pulled out and falls out.
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