what effect does sun have on skin ?

answers1: A few days of intense exposure to sun led to accelerated
aging of the skin. From this aspect, the fair skin is at disadvantage.
Darker the skin, more resistive it is to the harsh effects of the sun.
But the dark skins are not immune to it. Melanin, a pigment found in
the skin, protects the skin against the sunrays. And dark skin
contains more of this pigment. <br>
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Sunrays dehydrate the skin and make it dry rough and wrinkled, due to
this; pigmented spots and patches appear on the skin. This results in
the expansion of the blood vessels and hence the skin looks flushed
and red after sun-exposure and as a result, skin gradually tans. The
supporting fibres of the skin also get damaged and all this leds to
premature ageing.
answers2: Radiation from cosmic rays can damage cell structure and
cause cancers.