What describes the innermost layer of the skin?

The innermost layer of the skin is the hypodermis, also known as subcutaneous tissue. This layer is primarily made up of loose connective tissue and fat cells, which serve various functions. One of its main roles is to insulate the body and provide energy storage. Additionally, the hypodermis acts as a cushion, protecting underlying muscles and bones from external trauma. It also helps anchor the skin to underlying structures while allowing some degree of movement.

The other layers mentioned play different roles. The dermis, located just beneath the epidermis, contains fibrous connective tissue and is responsible for strength and elasticity of the skin, as well as housing blood vessels, hair follicles, and glands. The epidermis is the outermost layer, primarily made up of keratinized cells that provide a protective barrier. Subcutaneous fascia typically refers to the connective tissue just beneath the skin, but it is synonymous with the hypodermis in this context. Thus, understanding the structure and function of these layers helps clarify why the hypodermis is indeed identified as the innermost layer of the skin.