Action Spectrum - Red vs blue?

Plants!

Moderators: honeev, Leonid, amiradm, BioTeam

User avatar
Dr.Stein
King Cobra
King Cobra
Posts: 3501
Joined: Thu Jul 07, 2005 7:58 am
Location: 55284 Yogyakarta, Indonesia
Contact:

Re: Action Spectrum - Red vs blue?

Post by Dr.Stein » Fri Mar 16, 2007 2:36 am

Micky T wrote:Chlorophyll absorbs light at either red or blue wavelengths, but there is a definite difference between the two 'peaks' in increased rate of photosynthesis.

Does anyone know why this is? any information would be extremely handy as I cannot seem to find any useful information :(

They are chlorophyll A and chlorophyll B :)
Image

User avatar
Micky T
Death Adder
Death Adder
Posts: 66
Joined: Thu Jan 19, 2006 12:20 pm
Location: England

Post by Micky T » Fri Mar 16, 2007 8:20 am

no, i meant the two peaks within chlorophyll, like chlorophyll a had a blue peak and a red peak, as does chlorophyll b. Chlorophyll b will absorb blue more effeciently than red, whereas chlorophyll a will be just as effecient. I was wondering if there was a reason why a particular plant should absorb more blue light than red, and my previous post is the answer i've come up with - it's probably not right. :oops:
Madness takes its toll. Please have exact change.

User avatar
MrMistery
Inland Taipan
Inland Taipan
Posts: 6832
Joined: Thu Mar 03, 2005 10:18 pm
Location: Romania(small and unimportant country)
Contact:

Post by MrMistery » Sat Mar 17, 2007 3:57 pm

Ok, so
1. We don't know for sure what causes the specific action spectrum of the chlorophyll molecule. Hypothesises are that the specific shape of the molecule, the surrounding molecules and the proteins in the complexes contribute. Don't forget, P680 and P700 are both chl a, but have different absorbtion spectra.
2. The exact composition of pigments varies not only by species, but also by surrounding conditions. In shade, more chl b accumulates to help absorb more light. In intense light, more carotenes accumulate to help protect the plant. It is a very dimanic phenomenon...
Hope this is at least of some help.
Cheers.
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

User avatar
Dr.Stein
King Cobra
King Cobra
Posts: 3501
Joined: Thu Jul 07, 2005 7:58 am
Location: 55284 Yogyakarta, Indonesia
Contact:

Post by Dr.Stein » Sun Mar 18, 2007 2:01 am

I think it is preferences, I mean such chlorophyll works in a certain wavelenght, which red or blue are there... Pfff how to tell, my English sucks at the moment :(
Image

Post Reply

Who is online

Users browsing this forum: No registered users and 4 guests