Photosynthetic pigments found in members of the Rhodophyta
include chlorophyll-a, phycobilins such as phycoerythrin and phycocyanin,
and carotenoids. Chlorophyll-a is the primary photosynthetic pigment found
in all photosynthetic organisms, and the other pigments serve as accessory
pigments to capture energy from light at wavelengths not absorbed by chlorophyll
The main storage product of Gelidium, like other members of the
Rhodophyta, is floridean starge found in particles in the cytoplasm rather than
in the chloroplasts.
The important polysaccharides used in producing agar come from the cell wall
of Gelidium. Agar contains many different polysaccharides that
have the same backbone structure but include substitutions in their charged groups.
These polysaccharides contain D- and L-galactose units in alteration and are
best characterized physically due to their ability to form gels and viscous solutions
under appropriate conditions. Algal polysaccharides, including those from both
brown and red algae, are termed phycocolloids.
Morphology | Life History | Taxonomy | Chemistry | Distribution | Sources
© 1999 Sharon C. Komarow.
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