Red seaweed belongs to the phylum Rhodophyta, which takes its name from the greek rhodo (pink) and phyta (plant), an ancient, abundant, marketable organism with a unique way of reproduction. The red color of red seaweed is caused by phycoerythrin and phycocyanin, which mask other pigments, chlorophyll a (but not chlorophyll b), beta-carotene, and many unique luteins. The main reserves are usually rhubarb starch and emodin, there is no real starch like higher plants and green seaweed.
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