Here's why:

* Protozoa are single-celled eukaryotic organisms. This means they have a nucleus and other organelles within their single cell.

* Animal refers to multicellular organisms belonging to the kingdom Animalia. However, protozoa are considered animal-like because they are heterotrophic (meaning they consume other organisms for food) and often move around.

Examples of protozoa include:

* Amoeba: Moves using pseudopodia (temporary extensions of the cell).

* Paramecium: Covered in cilia (hair-like structures) for movement.

* Euglena: Has both plant-like (chloroplasts for photosynthesis) and animal-like (flagella for movement) characteristics.

Let me know if you'd like to learn more about any specific protozoa!