Dictionary » U » Ultraviolet

Ultraviolet

Ultraviolet

(Science: physics) continuous spectrum beyond the violet end of the visible spectrum (wavelength less than 400nm) and above the x-ray wavelengths (greater than 5 nm).

glass absorbs uv, so optical systems at these wavelengths have to be of quartz. Nucleic acids absorb uv most strongly at around 260nm and this is the wavelength most likely to cause mutational damage (by the formation of thymine dimers).

It is the uv component of sunlight that causes actinic keratoses to form in skin, but that is also required for vitamin d synthesis.


Please contribute to this project, if you have more information about this term feel free to edit this page



Results from our forum


receiving electromagnetism

I know that, in addition to our eyes, which can process visible light, there are some bird eyes that can process the smaller, ultraviolet waves (because of an extra pigment molecule, I think). In contrast, it seems unlikely that cells, which are small, could ever process radiowaves, which ...

See entire post
by wildfunguy
Sat Sep 29, 2012 10:46 pm
 
Forum: Cell Biology
Topic: receiving electromagnetism
Replies: 4
Views: 3546

Evolution and environment question--breathing, etc

With less ultraviolet light maybe it could be advantageous to lose pigments in our skin cells. That is something that can be genetically engineered.

See entire post
by OdinsRaven
Tue May 29, 2012 3:49 am
 
Forum: Evolution
Topic: Evolution and environment question--breathing, etc
Replies: 3
Views: 3552

Evolution and environment question--breathing, etc

... time in an environment which is slightly different from ours, here and there--perhaps a bit more nitrogen in the atmosphere, perhaps a bit less ultraviolet light to contend with. After that thousand years, they return to Earth looking and functioning with a notable difference in culture and ...

See entire post
by scifiwriter
Mon May 28, 2012 9:07 pm
 
Forum: Evolution
Topic: Evolution and environment question--breathing, etc
Replies: 3
Views: 3552

Theories - Origin of Life

... than it is now. This layer of ice, possibly hundreds of feet thick, might have protected fragile organic compounds in the water below from ultraviolet light and destruction from cosmic impacts. The cold might have also helped these molecules to survive longer, allowing key reactions to ...

See entire post
by einfopedia
Wed Mar 28, 2012 7:34 am
 
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 560
Views: 907061

Green mammals

... their main predators, birds and other insects, can see green. Most insects are sensitive to all colours except red and infrared, and can even see ultraviolet. A number of studies were cited by A. D. Imms FRS in his book 'Insect Natural History', however I haven't personally looked into these. ...

See entire post
by Squirrell
Tue Feb 21, 2012 9:39 pm
 
Forum: Zoology Discussion
Topic: Green mammals
Replies: 11
Views: 14758
View all matching forum results

This page was last modified 03:19, 30 September 2006. This page has been accessed 3,531 times. 
What links here | Related changes | Permanent link