protozoan
Single-celled creature
A protozoan is a single-celled organism, typically microscopic, that lives in water or as a parasite.
Protozoa include amoebas, paramecia, and the organisms causing malaria and dysentery.
The term groups creatures by their simple structure rather than evolutionary relationship—biologists now prefer more precise classifications, but protozoan remains useful shorthand for tiny, mobile, non-bacterial life.
Organism with nucleated cells
- cytoplasmGel surrounding the nucleus
- nucleusCentral controlling part
- pseudopodTemporary cellular projection
- flagellumWhiplike cellular appendage
cilia · vacuole · mitochondria · organelle · binary fission · phagocytosis · contractile vacuole · pellicle
Shape-shifting single-celled organism
- parameciumCiliated slipper-shaped protozoan
- euglenaPlant-animal hybrid microbe
- plasmodiumMultinucleate protoplasmic mass
- giardiaWaterborne intestinal parasite
ciliate · flagellate · vorticella · toxoplasma · cryptosporidium · entamoeba · babesia
Mosquito-borne parasitic infection
- plasmodiumMultinucleate protoplasmic mass
- toxoplasmosisParasitic infection from cats
- giardiasisProtozoan intestinal infection
- leishmaniasisSandfly-transmitted parasitic disease
trichomoniasis · dysentery · host · vector · lifecycle · transmission · dormant · carrier
Drifting marine microlife
- pondSmall still body
- freshwaterNon-saline aquatic environment
- marineRelating to the sea
- brackishMildly salty water
tidepool · estuary · wetland · sediment · biofilm · bloom · benthic · pelagic
Instrument for viewing minute objects
- slideSmooth continuous movement
- specimenIndividual for examination
- stainLasting surface discoloration
- cultureCollective social practices
petri dish · magnification · observation · motility · identification · laboratory · sample · preparation
Organism breaking down corpses
- grazerHerbivore eating low vegetation
- predatorOrganism that consumes others
- food webInterconnected predator-prey relationships
- bacteriaNucleus-free single-celled organisms
microbiome · soil · symbiont · bioindicator · ecosystem · microfauna · detritivore · consumer
eukaryote
Organism with nucleated cells
- cytoplasmGel surrounding the nucleus
- nucleusCentral controlling part
- pseudopodTemporary cellular projection
flagellum · cilia · vacuole · mitochondria · organelle · binary fission · phagocytosis · contractile vacuole · pellicle · cyst
amoeba
Shape-shifting single-celled organism
- parameciumCiliated slipper-shaped protozoan
- euglenaPlant-animal hybrid microbe
- plasmodiumMultinucleate protoplasmic mass
giardia · ciliate · flagellate · vorticella · toxoplasma · cryptosporidium · entamoeba · babesia
malaria
Mosquito-borne parasitic infection
- plasmodiumMultinucleate protoplasmic mass
- toxoplasmosisParasitic infection from cats
- giardiasisProtozoan intestinal infection
leishmaniasis · trichomoniasis · dysentery · host · vector · lifecycle · transmission · dormant · carrier · intestinal
plankton
Drifting marine microlife
- pondSmall still body
- freshwaterNon-saline aquatic environment
- marineRelating to the sea
brackish · tidepool · estuary · wetland · sediment · biofilm · bloom · benthic · pelagic · stagnant
microscope
Instrument for viewing minute objects
culture · petri dish · magnification · observation · motility · identification · laboratory · sample · preparation · iodine
decomposer
Organism breaking down corpses
- grazerHerbivore eating low vegetation
- predatorOrganism that consumes others
- food webInterconnected predator-prey relationships
bacteria · microbiome · soil · symbiont · bioindicator · ecosystem · microfauna · detritivore · consumer · biomass
- zoologymammals, reptiles, amphibians, birds, insects
- parasitestapeworm, roundworm, pinworm, hookworm, fleas
- eukaryotesanimals, animal, nucleus, fungi, plants
- microorganismsamoeba, paramecium, amoebae, euglena, amoebas
- Pathogenspathogen, germ, germs, bacteria, bacterium
- invertebratesinvertebrate, arthropod, arthropods, mollusk, crustacean
protozoananimal
Multicellular motile organism
vertebrate · mammal · human · plant · invertebrate