Hair is a biopolymer mostly made from keratin, which grows from the skin. Hair is exclusively found in mammals.

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3answers
2k views

Why does hair grow after trimming but remains at a constant length after a while?

Some hair especially body hair regrows after trimming but stops growing after a while. What is the mechanism behind control of hair growth and how is the length limit determined?
6
votes
1answer
554 views

Why did humans lose their fur?

The little amount of body hair humans have don't seem to be of much use for keeping warm. Our Simian cousins on the other hand sport thick furs. At which point during the species evolution and why ...
3
votes
1answer
460 views

What hair color will result in someone inheriting both blond and ginger genes?

Both the genes for blond hair and ginger hair are recessive, so they need both parents to give the same gene for it to take affect. What happens when a person has 1 copy of a recessive gene and ...
2
votes
2answers
639 views

Iron deficiency anemia symptoms explanation

In my classes and on the internet, brittle nails and dry hair (or hair loss) are described as symptoms of iron deficiency anemia, but none explains the cause of such symptoms. Does anyone have any ...