Question

Why hairs and nails grow?

Answer 1

Keratin is a protein made by cells in your skin that make up your hair and nails. As keratin cells naturally push upward through the skin, they die and then harden, turning into your hair or nails. ... Hair grows an average of 3 inches a year, whereas nailsusually grow about 1 1/2 inches a year

Answer 2

In order to protect us from dust to our sensetive organic.