UV Light Flashcards
1
Q
UV Light
A
short wavelength (4-400 nm)
2
Q
Visible light wavelengths
A
400-750 nm
3
Q
3 types of UV light
A
UVA longest
UVB
UVC shortest
4
Q
UVA
A
315-400 nm
5
Q
UVB
A
280-315 nm
6
Q
UVC
A
100-280 nm
7
Q
Most damaging wavelength of UV light
A
260 (UVC)
DNA maximally absorbs this wavelength
8
Q
Killing properties of UV light depend on
A
- wavelength
- time of exposure
- presence of materials to block the UV light
9
Q
Bacteria used in UV lab
A
Bacillus subtilis (endospore former) E. coli (non-spore former) Staph epi (non-spore former)
10
Q
Why are spores resistant to UV light
A
They are non-dividing cells so their DNA is never exposed
11
Q
Light Reactivation
A
Bacteria killed by UV can be reactivated when exposed to visible light
