What type of cells are found in the stratum basale?

The stratum basale, also known as the basal layer, is the deepest layer of the epidermis and is primarily composed of stem cells and melanocytes. The presence of stem cells in this layer is crucial, as they are responsible for the continuous regeneration of the skin by dividing and producing new keratinocytes, which will eventually move up through the layers of the epidermis. Melanocytes, which are also located within this layer, play an essential role in the production of melanin, the pigment that gives skin its color and provides some protection against UV radiation.

While other cell types mentioned in the choices play roles in the skin's structure and function, they are not primarily found in the stratum basale. Squamous cells, for instance, are more characteristic of the outer layers of the epidermis where keratinization occurs. Keratin-producing cells, primarily keratinocytes, begin their journey from the stratum basale but are most prominently found as they move up through the layers. Immune cells, such as Langerhans cells, are present in the epidermis but are typically located in the stratum spinosum rather than in the stratum basale. Hence, the distinctive presence of stem cells and melanocytes in