Anatomy of a Fingernail
The fingernail is the human equivalent of a bird claw — a hard, pointy, frequently sharp piece of anatomy made up of protein and keratin. Unlike a bird claw, however, the fingernail’s actual usefulness is in doubt.
Some interesting facts about fingernails:
- Nails grow on average 1 inch every 3 months (toenails grow slower)
- You can read a fingernail like a tree’s rings — to show history of recent health problems. Using fingernail health as a general medical diagnostic tool has been done since ancient times.
- Fingernails are made of the same material as human hair
- A major illness will often cause a deep groove (ake Beau’s lines) to form along a fingernail or toenail. The true cause of this symptom is unknown. Deep sea diving can also cause this groove to form for unknown reasons.
The juicy parts of the fingernail include