It secretes a pigment called melanin.
Melinin
vitamin D
Vitamin D production begins when a precursor molecule is exposed to ultraviolet light in the skin.
"What is the role of ACTH and melanin when the skin is exposed to ultraviolet light?"
Skin
When skin is exposed to ultraviolet (UV) light -- the type of light in sunlight -- several things happen. On the positive side, skin exposed to UV light makes vitamin D, an important nutrient. However, UV light also can cause an inflammatory -Dr Mehmet Oz
UV light is energetic and causes DNA damage to exposed skin. This DNA damage can result in cancers forming.
Skin cells do not produce a hat - no matter what kind of radiation falls on them.
You may experience sunburned skin if you allow your skin to be exposed to the ultraviolet waves that penetrate the clouds on a cloudy day. Ultraviolet waves are at the opposite end of the visible light spectrum from infrared waves. Ultraviolet (UV) waves are longer than X-rays.
Ultraviolet, or UV rays.
Ultraviolet radiation can be a cause of skin cancers.
If it is a human then the skin protects the entering of strong ultraviolet rays. In animals its the same. In plants the other covering of the cuticle protects to plant from being exposed to these rays.
The most common one is skin cancer but the most publicised one is skin cancer, rare but possible if exposed to even low levels of UV light
Ultraviolet light, corticosteroids, or skin grafts