Louisiana Esthetics State Board Practice Test

What is the basal cell layer also known as?

1. Stratum corneum

2. Stratum lucidum

3. Stratum germinativum

4. Stratum granulosum

The correct answer is: Stratum germinativum

The basal cell layer is known as the stratum germinativum because this layer is primarily responsible for the generation of new skin cells. It is the deepest layer of the epidermis, positioned just above the dermis, and plays a crucial role in skin regeneration and repair. In this layer, keratinocytes (the primary type of skin cell) undergo mitosis, producing new cells that migrate up through the epidermis to replace older cells that are shed from the skin's surface. This process is essential for maintaining the health and integrity of the skin. In contrast, other layers mentioned serve different functions. The stratum corneum, for example, consists of dead keratinized cells that provide a barrier to protect underlying tissues. The stratum lucidum, found only in certain areas of thick skin, offers additional protection. Finally, the stratum granulosum is where cells begin to lose their viability and prepare to become part of the outermost layer. Thus, the term stratum germinativum effectively captures the function and significance of the basal cell layer in skin biology.