Massachusetts State Board Esthetics Practice Exam

How many layers comprise the epidermis?

1. 2

2. 3

3. 5

4. 7

The correct answer is: 5

The epidermis is the outermost layer of skin and consists of five distinct layers, each with a specific function and characteristics. These are: 1. **Stratum Corneum**: The outermost layer, composed of dead keratinized cells. This layer provides a protective barrier and is continuously shed and replaced. 2. **Stratum Lucidum**: Found only in thicker skin areas (such as palms and soles), this translucent layer helps reduce friction and shear forces. 3. **Stratum Granulosum**: Here, keratinocytes begin to lose their nuclei and undergo a process of keratinization, producing keratohyalin granules that aid in the waterproofing of the skin. 4. **Stratum Spinosum**: This layer provides strength and flexibility to the skin, and is where the cells begin to change shape and become more irregular. 5. **Stratum Basale**: The deepest layer of the epidermis, this is where new skin cells are generated through mitosis, and it contains melanocytes, which produce melanin for skin pigmentation. Understanding the structure and function of these five layers is crucial for estheticians, as it informs various treatments and skincare recommendations. This knowledge is essential