What is the outermost layer of the skin called?

The outermost layer of the skin is known as the epidermis. This layer serves as the body's first line of defense against environmental factors such as bacteria, UV radiation, and pollutants. It is composed of several sub-layers, with the most superficial being the stratum corneum, which is made up of dead skin cells that continuously shed and renew. The epidermis plays a critical role in maintaining skin hydration, regulating temperature, and providing barrier functions.

The dermis, located beneath the epidermis, contains connective tissue, hair follicles, and glands but is not the outermost layer. The hypodermis, also not the outer layer, is a deeper layer of fat and connective tissue that anchors the skin to underlying structures like muscles and bones. Therefore, selecting the epidermis as the outermost layer reflects an understanding of skin anatomy and its protective functions.