Proteus amoeba, slipper ciliate and green euglena are not parasites. They do not depend on the life of other organisms. Some types of amoeba can enter the human or animal body and cause certain diseases, depending on the type of amoeba. But they do not parasitize in the body. Euglena green, in principle, will not be able to survive being inside the body of a person or an animal. She needs sunlight for photosynthesis. Parasites include nematodes, giardia, and other organisms not included in this list.
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