Book 2, Question 93
Why Do Hair and Nails Keep Growing?
Hair and nails keep growing because cells at their roots keep making new cells, and nails are made of keratin, the same tough protein as hair.
Your hair and nails never stop growing, so we need haircuts and nail trims. Tiny factories at the root keep adding new cells. Factories at the root!
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Quick answers
When do nails form?
You had fingernails and toenails before you were even born.
Sources: KidsHealth (Nemours), KidsHealth (Nemours)
From the book
Page from A Million Whys Book 2
More fun facts
- Nails are made of keratin, the same tough protein in hair and the top layer of skin.
- You had fingernails and toenails before you were even born.
- The hard surface of your nails protects the tips of your fingers and toes.
- Hair, skin, and nails together form the body's outer layer, called the integumentary system.
- Hair on your head protects you from the sun and helps keep you warm.
- Hair in your nose and ears helps keep out dust and other tiny bits.
Sources: KidsHealth (Nemours), KidsHealth (Nemours)
Questions kids ask
What are nails made of?
Keratin, the same tough protein that makes up your hair and the top layer of your skin.