Arizona Esthetics State Board Practice Exam

The subcutaneous layer, which lies beneath the dermis, is commonly referred to as the hypodermis. This layer primarily consists of loose connective tissue and fat that helps insulate the body and absorb shock. It also serves as a reservoir for energy and helps anchor the skin to underlying structures, such as muscles and bones.

The term "subdermis" does not hold a standard usage in anatomical references; hence, it may not be widely recognized as an alternative name for the subcutaneous layer. The dermis and the superficial layer are other distinct layers of the skin, with specific functions and tissue compositions that do not equate to the subcutaneous layer's role and structure. Thus, "hypodermis" is the most appropriate and scientifically accepted term synonymous with the subcutaneous layer.