Eukaryotes are organisms whose cells have a nucleus and other membrane-bound organelles.

While some eukaryotes are multicellular (like plants, animals, and fungi), many are single-celled organisms called protists. These protists include:

* Amoeba: These organisms move and feed using pseudopods (temporary extensions of the cell).

* Paramecium: These organisms have cilia (tiny hair-like structures) for movement.

* Euglena: These organisms have both plant-like chloroplasts for photosynthesis and animal-like flagella for movement.

So, although eukaryotes are known for their complex cellular structure, many of them live as single-celled organisms.