Illinois Nail Technician Practice Exam

What type of protein is found in the epidermis, hair, and nails?

1. Collagen

2. Keratin

3. Elastin

4. Actin

The correct answer is: Keratin

Keratin is the type of protein found in the epidermis, hair, and nails. It serves as a protective material and is crucial for maintaining the structural integrity of these tissues. In the epidermis, keratin contributes to the barrier function, helping to protect against environmental damage and prevent water loss. In hair and nails, keratin provides strength and durability, allowing them to withstand physical stress and maintain their shape. This protein is unique in its fibrous nature, which allows for the rigidity and resilience required in these features of the integumentary system. Collagen, while important for skin structure and elasticity, is primarily found in the dermis, not the outer epidermis, hair, or nails. Elastin also plays a role in skin elasticity but is not a component of hair or nails. Actin is a protein involved in muscle contraction and cellular movement, and it does not contribute to the structure of the epidermis, hair, or nails.