Amoebas can live in freshwater, marine, and terrestrial habitats. Pseudopods, false feet, are one characteristic that distinguishes amoebas from other protozoans. Amoebas also lack a cell wall and flagella. They engulf food particles forming food vacuoles. Like the amoebas, they also have pseudopods.
Zoomastigotes are protozoans that are unicellular, heterotrophic, and have at least one flagellum.
They are the most primitive of all protozoans and may be the early ancestors to the animal kingdom. Trypanosoma are one type of zoomastigina that cause African sleeping sickness and Chagas' disease. Ciliates are unicellular and have rows of cilia for movement. The more than 8000 species of ciliates may contain micro or macronuclei. Paramecium, one type of ciliate, is free-living and found in freshwater.