What type of skin cell is found in the Stratum Corneum and serves as a barrier to moisture loss?

The Stratum Corneum is the outermost layer of the epidermis and primarily consists of keratinocytes. These cells undergo a process called keratinization, where they produce keratin, a protective protein that toughens the skin and provides a significant barrier against moisture loss and environmental damage. As keratinocytes move toward the surface, they become flattened, lose their nuclei, and accumulate more keratin, forming the resilient structure of the Stratum Corneum.

While squamous cells refer to flat cells that can be found in various parts of the body, the specific function of forming a barrier in the Stratum Corneum is attributed to keratinocytes and their keratin production. Therefore, the correct choice emphasizes the critical role of keratinocytes in maintaining skin hydration and offering protection against trans-epidermal water loss.