Sunburn produces cell damage in the skin Why is ultraviolet radiation capable of producing this damage while visible radiation even if more intense is not?

Answer 1

By the wording of your question, I'm assuming you know some basic physics, but for those who don't, I'll do a quick summary.

Electromagnetic radiation, of which both visible light and UV radiation are a part, consists of photons (light particle-waves) of varying wavelengths. The wavelength of the radiation determines the energy it carries, they are inversely proportional. Thus, shorter wavelengths have a higher energy, and longer wavelengths have a lower energy.

The DNA inside skin cells can essentially be viewed as long, helical chain of molecules that are bonded together in specific ways. These bonds have specific energies associated with them, and if radiation with the right amount of energy (and hence the right wavelength) hits it, this bond can be broken. Usually, the cell is able to repair this damage. This is a complicated process which can easily be looked up, but I won't go into it here. Sometimes, however, mistakes occur during this repair, and these mistakes are replicated when the DNA is reproduced for further skin cell production.

Now that the background is established, back to the question. UV radiation, having a shorter wavelength than that of visible light, is energetic enough to break bonds in DNA, and thus to damage skin cells.

Answer 2

By the wording of your question, I'm assuming you know some basic physics, but for those who don't, I'll do a quick summary.

Electromagnetic radiation, of which both visible light and UV radiation are a part, consists of photons (light particle-waves) of varying wavelengths. The wavelength of the radiation determines the energy it carries, they are inversely proportional. Thus, shorter wavelengths have a higher energy, and longer wavelengths have a lower energy.

The DNA inside skin cells can essentially be viewed as long, helical chain of molecules that are bonded together in specific ways. These bonds have specific energies associated with them, and if radiation with the right amount of energy (and hence the right wavelength) hits it, this bond can be broken. Usually, the cell is able to repair this damage. This is a complicated process which can easily be looked up, but I won't go into it here. Sometimes, however, mistakes occur during this repair, and these mistakes are replicated when the DNA is reproduced for further skin cell production.

Now that the background is established, back to the question. UV radiation, having a shorter wavelength than that of visible light, is energetic enough to break bonds in DNA, and thus to damage skin cells.