Advanced Dental Admission Test (ADAT)

Which layer of the epidermis is responsible for the initial generation of new skin cells?

1. Stratum spinosum

2. Stratum granulosum

3. Stratum basale

4. Stratum corneum

The correct answer is: Stratum basale

The stratum basale is indeed the layer of the epidermis responsible for the initial generation of new skin cells. This lowest layer of the epidermis consists of a single row of columnar or cuboidal basal cells that are continually undergoing mitosis, producing new keratinocytes that eventually migrate up through the layers of the epidermis. This process is crucial for skin regeneration and repair, ensuring that as old and dead skin cells are shed from the surface, new cells are produced to replace them. The other layers play different roles in skin structure and function. The stratum spinosum, for example, provides strength and flexibility to the skin but is not primarily involved in generating new cells. The stratum granulosum is where keratinocytes begin to flatten and undergo keratinization, a process preparing them for eventual shedding from the skin's surface. Lastly, the stratum corneum consists of dead keratinized cells; while it serves as a protective barrier, it does not contribute to the generation of new skin cells.