What skin function relates to protection against environmental hazards?

The function of protection refers to the skin's primary role as a barrier against environmental hazards. This includes shielding the body from physical injuries, pathogens, and harmful substances such as chemicals and UV radiation. The skin's structure, particularly its outermost layer known as the stratum corneum, is designed to prevent the entry of microorganisms and to reduce water loss, thereby maintaining homeostasis. This protective characteristic is essential for overall health and well-being, as it helps to prevent infections and other complications that could arise from external threats.

In contrast, absorption relates to how the skin can take in certain substances, secretion refers to the process of producing and releasing substances such as sweat and oils, and excretion involves the removal of waste products. While these functions play important roles in skin physiology, they do not directly address the skin's primary role as a protective barrier.