What is the clear layer of the epidermis called?

The clear layer of the epidermis is known as the stratum lucidum. This layer is typically found only in thick skin areas, such as the palms of the hands and the soles of the feet. It serves an important role in providing an additional barrier and contributing to the skin's protective function. The stratum lucidum consists of flattened, dead keratinocytes that contain a protein called eleidin, which is a precursor to keratin, giving this layer a clear appearance. Its presence helps to reduce friction and shear forces in areas that experience a lot of mechanical stress, thus contributing to overall skin health and integrity.

In contrast, the stratum basale is the deepest layer of the epidermis where new skin cells are generated, and the stratum corneum is the outermost layer that consists of dead cells that have fully keratinized. The stratum granulosum lies between these layers, where keratinization begins and cells start to lose their nucleus and cytoplasmic organelles. Each of these layers plays a distinct role in the structure and function of the skin, but the stratum lucidum specifically is characterized by its clarity and unique composition.