There is a whole range of different pigments used in photosynthesis -
CHLOROPHYLLS
chlorophyll a - present in all higher plants and algae
chlorophyll b - present in all higher plants and green algae
chlorophyll c - diatoms and brown algae
chlorophyll d - red algae
(chlorophyll a is present in all photosynthetic organisms that evolve O2.)
Chlorophyll molecules contain a porphyrin 'head' and a phytol 'tail'. The polar (water-soluble) head is made up of a tetrapyrrole ring and a magnesium ion complexed with the nitrogen atoms of the ring. The phytol tail extends into the lipid layer of the thylakoid membrane.
CAROTENOIDS (carotenes and xanthophylls)
Carotenes:
"-carotene - higher plants and most algae
$-carotene - most plants & some algae
xanthophylls:
luteol, fucoxanthol and violaxanthol
Carotenoids contain a conjugated double bond system of the polyene type (C-C=C-C=C). Energy absorbed by carotenoids may be transferred to chlorophyll a for photosynthesis.
PHYCOBILINS (found mostly in red and blue-green algae):
phycoerythrin
phycocyanin
allophycocyanin )
Green plants have five closely-related photosynthetic pigments (in order of increasing polarity):
Carotene - an orange pigment
Xanthophyll - a yellow pigment
Chlorophyll a - a blue-green pigment
Chlorophyll b - a yellow-green pigment
Phaeophytin a - a gray-brown pigment
Phaeophytin b - a yellow-brown pigment
Chlorophyll a is the most common of the six, present in every plant that performs photosynthesis. The reason that there are so many pigments is that each absorbs light more efficiently in a different part of the spectrum. Chlorophyll a absorbs well at a wavelength of about 400-450 nm and at 650-700 nm; chlorophyll b at 450-500 nm and at 600-650 nm. Xanthophyll absorbs well at 400-530 nm. However, none of the pigments absorbs well in the green-yellow region, which is responsible for the abundant green we see in nature.
These links should give you the necessary info -
http://scitec.uwichill.edu.bb/bcs/courses/Biology/BL05B/2_autotrophic%20nutrition.htmhttp://www2.mcdaniel.edu/Biology/botf99/photo/p3igments.html GIVES SPECTRA AND STRUCTURE
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