| − | Any of a large group of single-celled, usually microscopic, eukaryotic organisms, such as amoebas, ciliates, flagellates, and sporozoans. Many protozoans are members of the kingdom [[protista]]. | + | Any of a large group of single-celled, sexually reproducing, usually microscopic, eukaryotic organisms, such as amoebas, ciliates, flagellates, and sporozoans. Many protozoans are members of the kingdom [[protista]]. |