This biological division contains the algal species Euglena and over 1,000 species of related algae; they are all unicellular (single-celled) and are mainly found in freshwater environments. They are all photosynthetic (though some are secondary heterotrophs) and they all contain chlorophyllsa and b. A unique feature of this division is that they store the energy they produce from photosynthesis as paramylum, an unusual carbohydrate. Members of this division have a contractile vacuole and a single flagellum.
Euglena is a genus of flagellate freshwater protozoans. It contains chlorophyll and is therefore photosynthetic, but it can also be mobile and gather its own food when sunlight is absent. Because it has the characteristics of both plants and animals, it is thought to be related to/similar to the ancestral organism which gave rise to both plants and animals.
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