Protozoa (in Greek protohi = first and zoa = animals) are unicellular eukaryotes, (singular protozoan). Bone marrow is the flexible tissue found in the hollow interior of Bones In adults marrow in large bones produces new Blood cells It constitutes 4% of Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex While there is no exact definition of the term, most scientists use protozoan to refer to a unicellular heterotrophic protist. Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this The name 'protozoa' is used for the more animal-like single celled organisms like amoebas and ciliates. The term 'algae' is used for the more plant-like micro organisms. However, the distinction between the two is often vague. Dinobryon (top image) has chloroplasts for photosynthesis but it can also feed on organic matter. It is even able to swim. Such an organism can neither be animal nor plant. Nowadays, all these unicellular organisms that are neither animals, plants, bacteria or fungi are called 'protists‘.
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Characteristics
Protozoa are around 10–50 μm but can grow up to 1 mm and can easily be seen under a microscope. A micrometre ( American spelling: micrometer; symbol µm) is one millionth of a Metre, or equivalently one thousandth of a Millimetre A microscope ( Greek: ( micron) = small + ( skopein) = to look or see is an instrument for viewing objects that are Protozoa exist throughout aqueous environments and soil. Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel Protozoa occupy a range of trophic levels. In Ecology, trophic dynamics is the system of trophic levels ( Greek trophē, food which describe the position that an organism occupies As predators, they prey upon unicellular or filamentous algae, bacteria, and microfungi. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Microfungi are Fungi, Eukaryotic Organisms such as Molds Mildews and rusts which exhibit tube tip-growth and Protozoa play a role both as herbivores and as consumers in the decomposer link of the food chain. Herbivory is a form of Predation in which an Organism, known as a herbivore, consumes principally Autotrophs ref name=Campbell>Campbell A heterotrophs, or chemoorganotrophy ( Greek heterone = (another and trophe = nutrition is an Organism that requires Food chains, also called food networks and/or trophic networks, describe the feeding relationships between species within an Ecosystem. Protozoa also play a vital role in controlling bacteria populations and biomass. Biomass refers to living and recently dead Biological material that can be used as fuel or for industrial production As components of the micro- and meiofauna, protozoa are an important food source for microinvertebrates. Fauna is all of the Animal life of any particular region or time Fauna is all of the Animal life of any particular region or time An invertebrate is an Animal lacking a Vertebral column. The group includes 98% of all animal Species — all animals except those in the Chordate 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 (Plasmodium spp. Malaria is a vector -borne Infectious disease caused by Protozoan Parasites It is widespread in tropical and subtropical regions including ), trypanosomes and leishmania are also important as parasites and symbionts of multicellular animals. Trypanosomes are a group of Kinetoplastid protozoa distinguished by having only a single Flagellum. Leishmania is a Genus of Trypanosome Protozoa, and is the Parasite responsible for the disease Leishmaniasis. Parasitism is a type of symbiotic relationship between Organisms of different Species. This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions
Most protozoa exist in 5 stages of life which are in the form of trophozoites and cysts. A trophozoite (G trope, nourishment + zoon, animal is the activated feeding stage in the life cycle of protozoan Parasites such as the malaria-causing A microbial cyst is a resting or Dormant stage of a microorganism usually a Bacterium or a Protist, that helps the organism to tide over unfavorable environmental As cysts, protozoa can survive harsh conditions, such as exposure to extreme temperatures and harmful chemicals, or long periods without access to nutrients, water, or oxygen for a period of time. Being a cyst enables parasitic species to survive outside of the host, and allows their transmission from one host to another. When protozoa are in the form of trophozoites (Greek, tropho=to nourish), they actively feed and grow. A trophozoite (G trope, nourishment + zoon, animal is the activated feeding stage in the life cycle of protozoan Parasites such as the malaria-causing The process by which the protozoa takes its cyst form is called encystation, while the process of transforming back into trophozoite is called excystation.
Protozoa can reproduce by binary fission or multiple fission. Some protozoa reproduce sexually, some asexually, and some both (eg. Coccidia). Coccidia are microscopic spore-forming single-celled parasites belonging to the Apicomplexan class Conoidasida. An individual protozoan is hermaphroditic.
Another name for protozoa is Acrita (R. Owen, 1861). It can also be considered Eukaryotic Cell Functionase
Classification
Protozoa were commonly grouped in the kingdom of Protista together with the plant-like algae and fungus-like water molds and slime molds. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins In biological Taxonomy, a kingdom or regnum is a Taxonomic rank in either (historically the highest rank or (in the new three-domain system Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this Plants are living Organisms belonging to the kingdom Plantae. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Oomycetes also known as Water molds (or water moulds: see spelling differences) are a group of filamentous unicellular Heterokonts physically Slime Mold is a broad term referring to amoeba-like organisms hence the name slime which feed on microorganisms in decaying vegetable matter hence the name Molds In the 21st-century systematics, protozoans, along with ciliates, mastigophorans, and apicomplexans, are arranged as animal-like protists. Biological systematics is the study of the diversity of Life on the planet Earth both past and present and the relationships among living things through time The ciliates are one of the most important groups of Protists common almost everywhere there is water — lakes ponds oceans rivers and soils with many ectosymbiotic Flagellates are cells with one or more whip-like organelles called flagella. However, protozoans are neither Animalia nor Metazoa (with the possible exception of the enigmatic, moldy Myxozoa). The Myxozoa ( Etymology: Greek: myx- "slime" or "mucus" + zoa "animals" are a group of parasitic
Sub-groups
Protozoa have traditionally been divided on the basis of their means of locomotion, although this is no longer believed to represent genuine relationships:
- Flagellates (eg. Flagellates are cells with one or more whip-like organelles called flagella. Giardia lambdia)
- Amoeboids (eg. Amoeboids are Unicellular lifeforms that mainly consist of Contractile vacuoles, a nucleus, and cytoplasm as their basic structure Entamoeba histolytica)
- Sporozoans (eg. Plasmodium knowlesi)
- Apicomplexa
- Myxozoa
- Microsporidia
- Ciliates (eg. The Myxozoa ( Etymology: Greek: myx- "slime" or "mucus" + zoa "animals" are a group of parasitic Microsporidia are parasites of animals now considered to be extremely reduced fungi. The ciliates are one of the most important groups of Protists common almost everywhere there is water — lakes ponds oceans rivers and soils with many ectosymbiotic Balantidium coli)
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