What is the function of the stratum corneum in skin?

The stratum corneum is the outermost layer of the epidermis and plays a crucial role in protecting the skin from environmental damage. Its primary function is to act as a barrier, preventing pathogens, chemicals, and physical irritants from penetrating deeper layers of the skin. This layer consists of dead skin cells that are tightly packed together and sealed with lipids, which helps to retain moisture within the skin while preventing external contaminants from entering.

Additionally, the stratum corneum helps to minimize water loss through transepidermal water loss (TEWL), which is vital for maintaining skin hydration. This protective feature is essential not only for the health of the skin but also for the overall health of the body since the skin acts as the first line of defense against various environmental threats.

The other options touch on different functions of the skin or its components but do not accurately describe the primary role of the stratum corneum. For example, while the skin does produce oil, this function is more attributable to sebaceous glands, and absorption is more related to the layers beneath the stratum corneum, where active metabolic processes occur. Healing is also a function associated with deeper layers and physiological responses rather than the outermost protective layer.