Utah Master Esthetician Practice Exam

What is the clear layer of the epidermis known as?

1. Stratum disjunction

2. Stratum granulosum

3. Stratum lucidum

4. Stratum reticulatum

The correct answer is: Stratum lucidum

The clear layer of the epidermis is known as the stratum lucidum. This layer is typically found only in the thicker skin areas of the body, such as the palms of the hands and the soles of the feet. It consists of several layers of dead keratinocytes that are densely packed with eleidin, a clear protein that ultimately transforms into keratin. This clear appearance helps to provide an additional barrier and enhances the protective function of the skin in areas subjected to friction and wear. The other layers mentioned do not fit this description. For instance, stratum granulosum refers to a layer where keratinocytes begin to lose their nuclei and undergo keratinization, while the stratum disjunction is not a recognized term in the context of skin layers. The stratum reticulatum is also not an epidermal layer but is rather part of the dermis. Understanding the specific functions and characteristics of these layers helps in appreciating their role in skin health and aesthetics.