The arrangement of photosynthetic membranes are similar. Red algae stores their food as floridean starch. No red algae has flagella, even in sperm cells. Most red algae are marine, with a few freshwater and terrestrial forms. The ancestors of all plants were undoubtedly members of phylum Chlorophyta.
Green algae show great diversity of form and live in a variety of habitats.
There is no tissue differentiation. The chloroplasts of algae contain chlorophylls a and b as well as beta carotene. They store their food as starch. The reproductive cycle demonstrates an alternation of generations. Spirogyra a typical green algae.