Wave lengths? HELP!!

Hallo to all
Sorry about the thread title not sure if it suits my question.
From what I've learned(not that much...YET) I understand the following:
Plants need certain wavelengths of light for photosynthesis purposes.

What i want to know is if i look at a graph representing the wavelength of a light source and it peaks in the blue and red spectrum, does that mean that the light only "Emmit's" the blue and red spectrum or is the blue and red spectrum's just more dominant(if that makes sense)?

Also want to know if i have 2x light sources one with a peak only in the red spectrum and the other one with a peak only in the blue spectrum, if i then "combine" the 2 lights would i have light with both spectrum's?

And finally if i have light source with a peak in the red spectrum only and i use it in my tank will the plants grow? I know that it would probably give my tank an awful colour but I'm asking this purely to better my understanding of how this works.

Please consider the questions as if the total luminance is correct for tank size:idea:
Any help or corrections will be much appreciated

 

Hi
there has been allot about lighting discussed on the forums and because i am lazy and am very busy i found that these links are very informative. These should answer all your questions .
http://www.tropicalaquarium.co.za/showthread.php?t=2648&highlight=lighting
http://www.tropicalaquarium.co.za/showthread.php?t=1853&highlight=lighting
http://www.tropicalaquarium.co.za/showthread.php?t=1853&highlight=lighting
http://www.americanaquariumproducts.com/Aquarium_Lighting.html
http://www.aquabotanic.com/lightcompare.htm

others will probably start helping soon but here is a bit of reading so long
Thanks
Antony

 

http://www.tropicalaquarium.co.za/showthread.php?t=3995
No Nonsense understandeable ,Hope this will help.
a bit too long to post here again.

Regards