Which component is primarily responsible for the skin's protection against UV radiation?

Melanin is the pigment primarily responsible for protecting the skin against ultraviolet (UV) radiation. It is produced by melanocytes, which are located in the epidermis. When the skin is exposed to UV rays, the production of melanin increases as a natural defense mechanism. Melanin absorbs UV radiation and dissipates it as heat, thus protecting the skin cells from damage that can lead to conditions such as sunburn, premature aging, and skin cancer.

In contrast, fibroblasts play a significant role in producing collagen and elastin, contributing to the skin's structural integrity but not directly to UV protection. The hydrolipidic film is a barrier that helps to keep the skin moisturized and protected against environmental factors, but it does not offer specific protection from UV rays. Epidermal growth factor is involved in cell growth and repair but again does not relate to the skin's protective measures against UV radiation.