Which layer of the epidermis is responsible for cell division?

The layer of the epidermis responsible for cell division is the stratum basale. This is the deepest layer of the epidermis, where keratinocytes, the primary cell type in the epidermis, are generated. In this layer, new cells undergo mitosis, which is the process of cell division. As these new cells are produced, they push older cells upwards through the epidermal layers, leading to the eventual formation of the outer protective layer of the skin.

In addition to keratinocyte production, the stratum basale also contains melanocytes, which produce the pigment melanin, and Merkel cells, which are involved in sensory perception. This layer is crucial for maintaining the skin's ability to repair itself and for adapting to various environmental conditions. The other layers mentioned do not significantly contribute to cell division; rather, they consist of more mature cells that have already migrated away from the stratum basale.