Which layer is the outermost layer of the skin?

• A. Dermis
• B. Hypodermis
• C. Subcutaneous layer
• D. Epidermis

Answer: (D)

The outermost layer of the skin is the epidermis. It forms the protective boundary you see on the surface, acting as a barrier against pathogens, physical damage, and UV radiation, while also helping to minimize water loss. The epidermis is avascular and is constantly renewed from the deeper basal layer, with the outermost part made up of dead, keratinized cells that provide a tough, waterproof surface.

Beneath the epidermis lies the dermis, which gives skin its strength and flexibility and contains blood vessels, nerves, hair follicles, and glands. Deeper still is the hypodermis (subcutaneous layer), composed mainly of fat and connective tissue that cushions and insulates the body.