An example of a single-celled organism is an amoeba. An amoeba is a protozoan that can temporarily form pseudopods to move about.
The word "amoeba" is derived from the Greek word "ameibein," which means to change. Its first known use was in 1855.
Protozoans are single-celled eukaryotes — organisms that have mobility like animals but are classified in the kingdom Protista. The amoeba is one of the simplest organisms in nature, yet it has cellular structure and DNA.
Some amoebas live on the bottom of freshwater ponds and streams. Others are found in the human digestive system.
Amoebas are used in cell research on the functions and interactions of cytoplasms and nuclei.