What is Protozoa?
Protozoans are microscopic, acellular, eukaryotic, heterotropic animalcules found either solitarily or in colonies generally in aquatic media or as parasites. Protozoa are single celled organisms.
Though protozoans were 1st discovered by Antony Von Leeuwenhock (1672) but the term protozoa was coined by Goldfuss (1809).
There are many protozoa, that cause various diseases in animals and humans, e.g. Plasmodium (malarial parasite), Trypanosoma (sleeping sickness), Trichomonas (trichomoniasis), etc.
Most species are free living, but all higher animals are infected with one or more species of protozoa.
