Karen is very nervous at her first job interview. Her hands are sweating so much that she thinks her fingernails are sweating. In reality, from which part of the nail unit is the sweat most likely arising?

• A. Nail bed
• B. Nail folds
• C. Nail plate
• D. Nail matrix

Answer: (B)

Sweat on the hands comes from sweat glands in the skin surrounding the nails. The nail folds are the skin flaps around the nail plate, and they are where sweat ducts open to the surface. The nail plate, nail bed, and nail matrix are mostly keratinized or internal structures and don’t release surface sweat. So when nerves trigger perspiration, the moisture would reveal itself at the nail folds—the skin edges around the nail plate.