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Related to protozoans: paramecium


1. of or pertaining to protozoa.
2. an organism belonging to the Protozoa.


1. A member of the phylum Protozoa. Synonym(s): protozoon
2. Relating to protozoa. Synonym(s): protozoal


(prō′tə-zō′ən) also


n. pl. proto·zoans or proto·zoa (-zō′ə) also proto·zoons
Any of numerous chiefly single-celled eukaryotic organisms, most of which move about freely and ingest food, including the amoebas, ciliates, flagellates, and apicomplexans. Protozoans along with certain algae, oomycetes, and some other groups make up the protists.

pro′to·zo′an, pro′to·zo′al, pro′to·zo′ic adj.


1. A member of the phylum Protozoa.
Synonym(s): protozoon.
2. Relating to protozoa.
Synonym(s): protozoal.


any member of the phylum Protozoa (sometimes regarded as a subkingdom of the animal kingdom), including unicellular or acellular organisms. The members of the group feed as HOLOPHYTES, SAPROPHYTES or in a HOLOZOIC manner, move by means of FLAGELLA, CILIA or PSEUDOPODIA, and reproduce by FISSION or CONJUGATION.

Protozoan (plural, protozoa)

A single-celled, usually microscopic organism, such as B. coli, that is eukaryotic and, therefore, different from bacteria (prokaryotic).
References in periodicals archive ?
A survey of intestinal protozoan and helminth parasites in Karachi.
KEY WORDS: Endo-parasites, Prevalence, Vicinity, protozoan parasites, Helminth parasites, Hypoproteinaemia, Mortality, Growth, Grazing, Pasture
Concerning protozoan parasites, recent research indicates that ultraviolet light will inactivate Giardia or Cryptosporidium.
Entamoeba coli and Endolimax nana were the most commonly detected protozoan parasites, while Isospora, Cryptosporidia and other Coccidia species were less common (Table I).
There were ten species of parasites infecting the different organs of the fish samples, namely Protozoans: Oodinium pilluris (egg), Chilodonella sp., Coccidia sp., and Cryptobia sp.; Nematodes: Capillaria sp., Procamallanus sp., Spirocamallanus sp., and Camallanus sp.; Cestode: Hymenolypis nana; and Acanthocephala: Acanthocephalus sp.
The ciliate protozoan, Nyctotherus cordiformis, is a cosmopolitan parasite of frogs and toads and, while it is not surprising that S.
The order of their divergence is still uncertain, but is important in relation to the origin of the trans-splicing that characterizes nuclear genes in Euglenozoa, and stands in contrast with the cis-splicing of Percolozoa and the nine higher protozoan phyla.
Indirect effects in each of these two-consumer food webs were produced by strong competitive interactions between pairs of protozoans. There was a clear dominance hierarchy among the three protists.
Protozoans engulf their prey and incorporate it into a food vacuole within the cell where it is subjected to harsh chemical treatment involving digestive enzymes and acidic conditions.
The 24 following chapters, ranging from the protozoans to the pelecypods, provide succinct reviews of the various groups' general characteristics, historical notes on early studies of them, foods and feeding, biology, general ecology, reproduction, dispersal and geographical distribution, collecting and preserving, culture (where appropriate), taxonomy, and much more.