Information AboutProtozoa |
| CATEGORIES ABOUT PROTOZOA | |
| obsolete taxonomic groups | |
| microbiology | |
| protista | |
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Protozoa (in Greek ''proto'' = first and ''zoa'' = animals) are One-celled Eukaryotes (that is, Unicellular Microbe s whose cells have membrane-bound Nuclei ) that commonly show characteristics usually associated with Animal s, most notably Mobility and Heterotrophy . '''Protozoans''' were commonly grouped in the Kingdom Protista together with the Plant -like Algae and fungus-like Water Mold s and Slime Mold s. In 21st-century Systematics , however, most of the algae are classified in kingdoms such as Plantea and Chromista ; and in such cases the remaining life forms are occasionally classified as a kingdom Protozoa. But the name is misleading, since '''protozoans''' are neither Animalia nor Metazoa , with the ''possible'' exception of the enigmatic, moldy Myxozoa ). Protozoa have traditionally been divided on the basis of their means of locomotion, although this is no longer believed to represent genuine relationships:
Most protozoa are too small to be seen with the naked eye—most are around 10–50 μm , but forms up to 0.5 mm exist—but can easily be found under a Microscope . Protozoa are ubiquitous throughout Aqueous environments and the Soil , and play an important role in their Ecology . Protozoa occupy a range of Trophic Level s. As predators upon unicellular or filamentous algae, Bacteria , and Microfungi , protozoa play a role both as Herbivore s and as Consumer s in the decomposer link of the Food Chain . Protozoa also play a vital role in controlling bacteria population and Biomass . As components of the Micro- and Meiofauna , protozoa are an important food source for Microinvertebrate s. Thus, the ecological role of protozoa in the transfer of bacterial and algal production to successive trophic levels is important. Protozoa such as the Malaria parasites, Trypanosome s and Leishmania are also important as Parasite s and Symbiont s of Multicellular animals. Some protozoa have the ability to form a cyst to protect it from harsh conditions, allowing it to survive exposure to extreme temperatures or harmful chemicals or without food, water, or oxygen for a period of time. For parasitic species the cyst will also enable it to survive outside of the host, allowing it to be transferred from one host to another. An individual protozoan is both male and female. Another name for protozoa is Acrita (R. Owen, 1861). EXTERNAL LINKS http://ucjeps.berkeley.edu/cgi-bin/porp_cgi.pl?ACRITAROWEN1861] |
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