MadSci Network: General Biology |
Good question. The thing is, the cells inside the hair itself don't grow; as you pointed out, they're dead. Hair grows from below; it's pushed out of little hair-generating pits in the skin called follicles. Here's a picture: http://upload.wikimedia.org/wikipedia/commons/4/49/HairFollicle.png What divides are the cells in the follicles - and they do it very quickly. If you look closely at the hairs on your arm, you may be able to see the outer part of the follicles, which can be slightly discolored or pitted. Thanks for asking!
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