American Academy of Professional Coders (AAPC) Practice Exam

The number of stratum layers in the epidermis varies based on what factor?

1. Exposure to sunlight

2. Location of the epidermis

3. Skin color

4. Age of the individual

The correct answer is: Location of the epidermis

The number of stratum layers in the epidermis varies based on the location of the epidermis in the body. Different regions of the skin serve different functions and are subject to varying degrees of wear and exposure, which influences the structure of the epidermis. For instance, areas that experience more friction, such as the palms of the hands and soles of the feet, have a thicker epidermis with more layers, specifically in the stratum corneum, to provide additional protection. Conversely, areas with less exposure and less friction may have a thinner epidermis with fewer layers. This variability in the epidermal structure ensures that the skin can adequately protect underlying tissues while accommodating the specific needs of different body areas.