Question

What risks does ultraviolet and infrared pose to humans?

Answer 1

UV - Initiate benign and malign skin cancer. Damage the immunologic system. Provoque damages to eyes, including cataracts, the cornea can absorb this radiation quite easily. They make sunburn a lot more severe and skin old.
IR - The transparent part of the eyes, being of aqueous composition, absorb the IR, with the existing risk of the cornea get hot excessively. The crystalline can also be damaged, as well as the retina.

Answer 2

gud ans by @liliaKarina adding a little to this
uv light causes formation of pyrimidine dimmers in DNA that is y causes cancer if not repaired.

Answer 3

http://www.web-books.com/MoBio/Free/Ch7F5.htm
Here theres is a good picture of the Mutation by UV light

Answer 4

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