Which of the following is NOT a function of the skin?

The skin plays a vital role in several essential functions of the body, including temperature regulation, immunity, and protection. However, digestion is not one of the skin's functions. The skin primarily serves as a protective barrier, regulating body temperature through sweat glands and blood vessels, and providing immune defense through various cells that respond to pathogens.

Understanding the distinct functions of the skin helps clarify why digestion is not included. Digestion occurs in the gastrointestinal tract, where food is broken down and nutrients are absorbed. The integumentary system, which includes the skin, does not participate in this process. This distinction is crucial for grasping the unique roles that different body systems play.