Which of the following terms is considered an appendage of the skin?

• A. Nail
• B. Hair
• C. Sweat gland
• D. Muscle

Answer: (A)

Skin appendages are structures that originate from the epidermis and extend outward from the skin to perform specific roles. The nail is the clear example here: it’s a hard keratin plate that sits on the fingertip, produced by the nail matrix beneath the cuticle, and it grows from the skin. Because it derives from epidermal tissue and remains attached to the skin’s surface, it’s considered an appendage of the skin. The muscle isn’t part of the skin’s outward extensions, while hair and glands are also skin-related structures, but in this context the nail is the classic, readily identified skin appendage used in nail technology.