Nail - Skin Derivative

Nails are derivatives of the skin. They consist of cells rich in keratin, that is, keratinized cells. The exposed part of the nail is the nail body. It is transparent, so the blood capillaries give it its characteristic pink color.

The nail grows from the crater - a white crescent on the bottom - to the free edge, or the edge that protrudes above the pad of the finger. The inner part of the nail is formed by the nail bed. Under the hole there is a place where the nail grows, consisting of various blood vessels and nerve endings. This is where nail growth begins: on the hands, a new nail grows to replace the one that fell off in three months.

A single handprint contains up to 250 billion particles of hand sweat, which allows dogs to follow a person's scent using their sense of smell.