When you are exposed to sunlight for a long time, your skin, which otherwise appears normal, gets heavily tanned. what could be the reason?

Our skin gets tanned by getting exposed to sunlight due to the production of melanin as a protective measure.

Explanation:

Electromagnetic waves like infrared waves and UV rays are present in sunlight.  While infrared rays maintain the earth’s atmospheric heat UV rays doesn’t prove to be helpful. UV rays that penetrate the skin damages the DNA and RNA .  

The body has developed a fighting mechanism to tackle this problem. That method is the production of melanin, which is the colouring pigment in human skin. The melanin reduces the penetration of UV rays into the skin.  

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