Knowra Protozoa Protozoa Protozoa are a traditional grouping of mostly single-celled eukaryotes, including amoebas, ciliates, and flagellates, that are not classified as animals, plants, or fungi.
Eukaryote : An organism whose cells contain a nucleus and other membrane-bound compartments. Protozoa belong to this broad group because their cells contain nuclei.
Pseudopod : A temporary cell projection used for movement or engulfing particles. Amoebas extend pseudopods to crawl and capture food.
Plasmodium : A genus of parasitic alveolates that causes malaria in humans and other animals. Its life cycle illustrates how a protozoan parasite can depend on multiple hosts.
Animal : A multicellular eukaryote that obtains nutrients by ingestion and belongs to kingdom Animalia. Protozoa were historically distinguished from animals despite some animal-like traits.
Unicellular organism : An organism composed of a single cell that carries out its life functions. Most protozoa are single-celled, though some form colonies or complex life stages.
Cilium : A short, hairlike cell projection that can move fluid or propel a cell. Ciliates coordinate rows of cilia to swim and direct food toward cell openings.
Giardia duodenalis : A flagellated intestinal parasite that causes giardiasis in humans and other mammals. Its cysts spread through contaminated water, linking protozoan biology to sanitation.
Plant : A multicellular eukaryote in the land-plant lineage, typically adapted to photosynthesis. The traditional grouping excluded plants, though some protists photosynthesize.
Protist : An informal grouping of eukaryotes that are not animals, plants, or fungi. Protozoa have historically been treated as a subset of this broad grouping.
Flagellum : A long, whip-like cell projection that propels a cell or moves fluid. Flagellates use one or more flagella for locomotion and, sometimes, feeding.
Show all 22