English: The anatomy of the protist Euglena Euglena are unicellular, flagellate protists of the genus Euglena and kingdom Eukarya. Able to photosynthesize with their chloroplasts and also capable of accessing food from outside sources, they are both autotrophic and heterotrophic. Euglena have both plantlike and animalistic qualities: they contain chloroplasts, but have a pellicle, an envelope made up of many microtubules allowing for fluid, smooth movement in their environment. Although they are eukaryotic organisms, they reproduce asexually through binary fission. Some components of the anatomy of euglena are very unique: Euglena have two flagella, even though only one is visible outside the cell: the second flagellum does not protrude out of the reservoir. The red eyespot of a euglena filters light for the photoreceptor so that only certain wavelengths of light are able to reach the photoreceptor, allowing the euglena to “steer” itself by moving toward light in different intensities in different areas of its photoreceptor. Key: 1. Microtubules that make up the pellicle (see 9.) 2. Contractile Vacuole 3. Stigma / Eyespot 4. Flagella 5. Reservoir 6. Photoreceptor / Paraflagellar Body 7. Basal Bodies 8. Chloroplast 9. Pellicle 10. Nucleus 11. Nucleolus