Biology 20 HELP PLEASE!!! I have two questions regarding how UVR effects animals? HELP!!?

Question

Okay so i have two questions (although similar) but two separate answers would be preffered.

1. What direct effects does increasing UVR have on animals?

2. What indirect effects does increasing UVR have on animals?

Answer 1

Direct and indirect

UVA, UVB and UVC can all damage collagen fibers and thereby accelerate aging of the skin. Both UVA and UVB destroy vitamin A in skin which may cause further damage. In the past UVA was considered less harmful, but today it is known, that it can contribute to skin cancer via the indirect DNA damage (free radicals and reactive oxygen species). It penetrates deeply but it does not cause sunburn. UVA does not damage DNA directly like UVB and UVC, but it can generate highly reactive chemical intermediates, such as hydroxyl and oxygen radicals, which in turn can damage DNA. Because it does not cause reddening of the skin (erythema) it cannot be measured in the SPF testing. There is no good clinical measurement of the blocking of UVA radiation, but it is important that sunscreen block both UVA and UVB. Some scientists blame the absence of UVA filters in sunscreens for the higher melanoma-risk that was found for sunscreen users.

Eyes :

Protective eyewear is beneficial to those who are working with or those who might be exposed to ultraviolet radiation, particularly short wave UV. Given that light may reach the eye from the sides, full coverage eye protection is usually warranted if there is an increased risk of exposure, as in high altitude mountaineering. Mountaineers are exposed to higher than ordinary levels of UV radiation, both because there is less atmospheric filtering and because of reflection from snow and ice.

Ordinary, untreated eyeglasses give some protection. Most plastic lenses give more protection than glass lenses, because, as noted above, glass is transparent to UVA and the common acrylic plastic used for lenses is less so. Some plastic lens materials, such as polycarbonate, inherently block most UV. There are protective treatments available for eyeglass lenses that need it which will give better protection. But even a treatment that completely blocks UV will not protect the eye from light that arrives around the lens.

Source(s):

http://en.wikipedia.org/wiki/Ultra_viole...