An example of an autotrophic protist is the euglena. It has a single cell and makes its own food through the process of photosynthesis, just like plants, according to Fairfax County Public Schools. The euglena eats green algae, incorporating the algae's chloroplasts to make food for the euglena.
Euglenas live in bodies of water. The chloroplasts inside a euglena make it look green. When it cannot find the light to make its own food, the euglena can also consume other organisms; therefore, the euglena is an organism that is both autotrophic and heterotrophic.
The euglena has a special protective layer called a pellicle. One end of the euglena contains the flagellum by which the organism moves through water. The euglena can sense light with its eyespot.