Lagen van de Epidermis

The epidermis, the topmost layer of the skin, is made up of four to five distinct layers of cells.

The stratum basale is the deepest layer attached to the underlying dermis. It is primarily made up of keratinocytes and a small number of melanocytes, tactile epithelial cells, and stem cells.

As the stem cells divide, the newly formed keratinocytes are pushed up into the stratum  spinosum, which has multiple layers of keratinocytes attached together by desmosomes.

Superior to spinosum, the stratum granulosum has 3 to 5 layers of keratinocytes, which undergo keratinization, making the cells thinner and flatter.

Moreover, the keratohyalin granules promote cell dehydration and increase cross-linking of keratin fibers. Eventually, cells lose organelles and die.

The Stratum lucidum is a thin translucent layer of keratin-rich dead keratinocytes found only in the thick skin of the palm and the sole.

The stratum corneum is the outermost layer of the epidermis, largely consisting of anucleated dead cells called corneocytes. This layer protects the skin from abrasions and is water-resistant.