What is the primary function of keratinocytes in the skin?

The primary function of keratinocytes in the skin is to produce keratin, a type of protein that is essential for creating a protective barrier on the surface of the skin. Keratin is crucial for skin integrity and resilience, as it helps to shield underlying tissues from damage, pathogens, and dehydration. This protective role is vital for maintaining overall skin health and function.

Keratinocytes comprise the majority of cells in the epidermis, the outermost layer of the skin. As these cells mature, they move from the basal layer to the surface, undergoing a process known as keratinization, where they become filled with keratin and eventually die off, forming a tough protective layer.

The other options, while they touch on important skin functions, do not represent the primary role of keratinocytes. For instance, collagen production is primarily the job of fibroblasts in the dermis and is important for skin elasticity, but it is not related to keratinocytes. The absorption of nutrients is more associated with other cell types and systems in the skin, and body temperature regulation is managed by different mechanisms, including sweat glands and blood vessels, rather than keratinocytes themselves. Thus, the production of keratin stands out as the main function of keratin