Copy of PM from Linkinpark08 below:
LinkinParkRulez08 Online
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Default UVB Lights - Today, 10:37 AM
http://en.wikipedia.org/wiki/Photosy...hemical_energy
It is part of Photosynthesis. It doesnt say UVB but it says light and UVA and UVB are usually the ones that are not absorbed that much.
Hope this helps with your research
1.0 Vield, 3.4 Bearded Dragons, 1.0 Chinese Water Dragons, 1.0 Mali Uromastyx
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Linkin..thanks for the PM...its copied at the top of this post.
So, now, your Wikipedia link suggests that UVB is not a major contributor to plant photosynthesis???? Is that a contradiction of the info you quoted from your academic text.
BTW, please quote that texts name and author.. Id still like to aquire it ....
Natural sources of UV
The Sun emits ultraviolet radiation in the UVA, UVB, and UVC bands, but because of absorption in the atmosphere's ozone layer, 99% of the ultraviolet radiation that reaches the Earth's surface is UVA. (Some of the UVB and UVC radiation is responsible for the generation of the ozone layer.)
Ordinary glass is partially transparent to UVA but is opaque to shorter wavelengths while Silica or quartz glass, depending on quality, can be transparent even to vacuum UV wavelengths. Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm.[2][3][4]
The onset of vacuum UV, 200 nm, is defined by the fact that ordinary air is opaque below this wavelength. This opacity is due to the strong absorption of light of these wavelengths by oxygen in the air. Pure nitrogen (less than about 10 ppm oxygen) is transparent to wavelengths in the range of about 150–200 nm. This has wide practical significance now that semiconductor manufacturing processes are using wavelengths shorter than 200 nm. By working in oxygen-free gas, the equipment does not have to be built to withstand the pressure differences required to work in a vacuum. Some other scientific instruments, such as circular dichroism spectrometers, are also commonly nitrogen purged and operate in this spectral region.
Extreme UV is characterized by a transition in the physics of interaction with matter: wavelengths longer than about 30 nm interact mainly with the chemical valence electrons of matter, while wavelengths shorter than that interact mainly with inner shell electrons and nuclei. The long end of the EUV/XUV spectrum is set by a prominent He+ spectral line at 30.4nm. XUV is strongly absorbed by most known materials, but it is possible to synthesize multilayer optics that reflect up to about 50% of XUV radiation at normal incidence. This technology has been used to make telescopes for solar imaging; it was pioneered by the NIXT and MSSTA sounding rockets in the 1990s; (current examples are SOHO/EIT and TRACE) and for nanolithography (printing of traces and devices on microchips).
A positive effect of UVB exposure is that it induces the production of vitamin D in the skin. It has been estimated that tens of thousands of premature deaths occur in the United States annually from a range of cancers due to vitamin D deficiency.[5] Another effect of vitamin D deficiency is osteomalacia (the adult equivalent of rickets), which can result in bone pain, difficulty in weight bearing and sometimes fractures. Other studies show most people get adequate Vitamin D through food and incidental exposure.[6]
Many countries have fortified certain foods with Vitamin D to prevent deficiency. Eating fortified foods or taking a dietary supplement pill is usually preferred to UVB exposure, due to the increased risk of skin cancer from UV radiation.[6]
Ultraviolet radiation has other medical applications, in the treatment of skin conditions such as psoriasis and vitiligo. UVA radiation can be used in conjunction with psoralens (PUVA treatment). UVB radiation is rarely used in conjunction with psoralens. In cases of psoriasis and vitiligo, UV light with wavelength of 311 nm is most effective
It is also used for calcium and vitamin D3 absorbtion, above explains some of it. UVA is used in plants.... I might have mixed them up but I'm pretty sure that UVA is for plants and UVB is for Animals. Also, UVB has some parts in Plants
