Freshwater Green Algae make up the division Chlorophyta, which includes about 7,500 species of eukayotic, unicellular organisms. Some of the unifying characteristics of this division include similar photosynthetic pigments that make up the chloroplast, which include Chlorophylls a and b, and a -, b -, and g -carotenes; and some xanthophylls and primary carotenoids.