| MadSci Network: General Biology |
Initially, there’s two ways to understand the question. You’ve mentioned
the darkening of skin when exposed to ultra-violet rays. It happens
because light rays in ultra-violet range are more energetic than the other
colors of visible light spectrum. The skin, when exposed to these rays,
produces melanin, a substance that acts like a solar filter, protecting
the skin from burning. Other frequency rays (the frequency determines
the color of light) don’t make the skin release melanin as the ultra-
violet does... BUT, by the Physics point of view, every atom (and so your
skin cells) reacts to the light, which is made of photons. These photons
interact with the electrons of the atoms in your cells, producing
vibration on these atoms. It’s the molecular description of heat. If the
light rays excite your atoms enough, your local nerves, and then your
brain, will react and feel this heat. That’s a kind of “neurobiological”
detection.
Hope this is useful
D..!
Any doubts to escrutinador@hotmail.com
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