Wound, Ostomy and Continence Nurses Society (WOCN) Practice Exam

What is the top layer of skin called?

1. Dermis

2. Subcutaneous tissue

3. Stratum corneum

4. Basement membrane zone

The correct answer is: Stratum corneum

The top layer of the skin is referred to as the stratum corneum. This layer is a crucial part of the epidermis, which is the outermost layer of skin. The stratum corneum is composed of dead skin cells that have undergone a process called keratinization, where they are filled with keratin, a protective protein. This layer serves multiple important functions: it acts as a barrier to prevent the loss of moisture from the body, protects underlying tissues from environmental damage, and helps to reduce the risk of infection by providing a tough outer covering. It plays a vital role in the overall health and integrity of the skin. Other layers mentioned, such as the dermis, subcutaneous tissue, and basement membrane zone, serve different functions and are located beneath or supported by the epidermis. For instance, the dermis contains blood vessels, nerves, and connective tissue, and the subcutaneous tissue acts as an insulating layer that helps to regulate body temperature. The basement membrane zone provides a structural foundation for the epidermis but is not considered the top layer of the skin.