Which term describes the outermost layer of the skin?

The outermost layer of the skin is known as the epidermis. It serves as a protective barrier against environmental damage, pathogens, and moisture loss. This layer is primarily composed of keratinocytes, which produce keratin, a protein that helps waterproof the skin and maintain its integrity.

The epidermis itself contains various sub-layers, with the stratum corneum being the topmost layer of the epidermis, consisting of dead skin cells that are continuously shed and replaced. While "stratum corneum" relates to a specific part of the epidermis, the term "epidermis" encompasses the entire outer layer of skin, making it the correct term for the question about the outermost layer.

The dermis and subcutaneous layers reside beneath the epidermis, with the dermis providing structural support through connective tissue and housing blood vessels and hair follicles, while the subcutaneous layer primarily consists of fat and connective tissue, serving as insulation and cushioning for the skin and underlying structures.