FACTOID # 6: Michigan is ranked 22nd in land area, but since 41.27% of the state is composed of water, it jumps to 11th place in total area.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Protist" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Protist
Protists
Fossil range: Neoproterozoic - Recent

Scientific classification
Domain: Eukarya
Whittaker & Margulis, 1978
Kingdom: Protista*
Haeckel, 1866
Typical phyla

Protists (IPA: /ˈprəʊ.tɪst/ (RP); /ˈproʊ.tɪst/ (GenAm)), Greek protiston -a meaning the (most) first of all ones, are a diverse group of organisms, comprising those eukaryotes that cannot be classified in any of the other kingdoms as fungi, animals, or plants. They are usually treated as the kingdom Protista or Protoctista. Protoctists (or protists) are a paraphyletic grade, rather than a natural, (monophyletic) group, and so do not have much in common besides a relatively simple organization -- either they are unicellular, or they are multicellular without highly specialized tissues. Essentially, the Kingdom Protista is comprised of organisms that cannot be classified into any other kingdom. The term protista was coined by Ernst Haeckel in 1866. The Neoproterozoic Era is the unit of geologic time from 1,000 to 542 +/- 0. ... Image File history File links Size of this preview: 689 × 600 pixelsFull resolution (1220 × 1062 pixel, file size: 269 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... Robert Whittaker (1920-1980) was an American vegetation ecologist, active in the 1950s through the 1970s. ... Lynn Margulis Dr. Lynn Margulis (born March 15, 1938) is a biologist and University Professor in the Department of Geosciences at the University of Massachusetts Amherst. ... In phylogenetics, a grouping of organisms is said to be paraphyletic (Greek para = near and phyle = race) if all the members of the group have a common ancestor, but the group does not include all the descendants of the most recent common ancestor of all group members. ... Ernst Haeckel. ... 1866 (MDCCCLXVI) is a common year starting on Monday of the Gregorian calendar or a common year starting on Wednesday of the 12-day-slower Julian calendar. ... The chromalveolates (Chromalveolata) are a hypothetical grouping of eukaryotes, comprising the Chromista and alveolates, as suggested by Tom Cavalier-Smith. ... Phyla Heterokontophyta Haptophyta Cryptophyta The Chromista are a eukaryotic supergroup, which may be treated as a separate kingdom or included among the Protista. ... Typical classes Colored groups Chrysophyceae (golden algae) Synurophyceae Actinochrysophyceae (axodines) Pelagophyceae Phaeothamniophyceae Bacillariophyceae (diatoms) Bolidophyceae Raphidophyceae Eustigmatophyceae Xanthophyceae (yellow-green algae) Phaeophyceae (brown algae) Colorless groups Oomycetes (water moulds) Hypochytridiomycetes Bicosoecea Labyrinthulomycetes (slime nets) Opalinea Proteromonadea The heterokonts or stramenopiles are a major line of eukaryotes containing about 10,500... Orders Class Pavlovophyceae    Pavlovales Class Prymnesiophyceae    Prymnesiales    Phaeocystales    Isochrysidales    Coccolithales The haptophytes, classed either as the Prymnesiophyta or Haptophyta, are a group of algae. ... Typical genera Campylomonas Chilomonas Chroomonas Cryptomonas Falcomonas Geminigera Goniomonas Guillardia Hemiselmis Plagioselmis Proteomonas Storeatula Rhodomonas Teleaulax The cryptomonads are a small group of flagellates, most of which have chloroplasts. ... The alveolates are a major line of protists. ... Classes Dinophyceae Noctiluciphyceae Syndiniophyceae The dinoflagellates are a large group of flagellate protists. ... Classes & Subclasses Aconoidasida Haemosporasina Piroplasmasina Blastocystea Conoidasida Coccidiasina Gregarinasina The Apicomplexa are a large group of protozoa, characterized by the presence of a unique organelle called an apical complex. ... Classes Karyorelictea Heterotrichea Spirotrichea Litostomatea Phyllopharyngea Nassophorea Colpodea Prostomatea Oligohymenophorea Plagiopylea See text for subclasses. ... A Bikont is a eukaryotic cell with two flagella. ... The excavates are a major line of protists, often known as Excavata. ... Typical Classes Euglenoidea Kinetoplastea Diplonemea Postgaardea The Euglenozoa are a large group of flagellate protozoa. ... The Percolozoa are a group of colorless protists including many that can transform between amoeboid, flagellate, and encysted stages, collectively referred to as schizopyrenids or amoeboflagellates. ... Classes & orders Eopharyngia    Retortamonadida    Diplomonadida    Carpediemonas Parabasalia Anaeromonada    Oxymonadida    Trimastix The metamonads are a group of flagellate protozoa, including the retortamonads, diplomonads, and possibly the parabasalids and oxymonads as well. ... Phyla Cercozoa Foraminifera Radiolaria The Rhizaria are a major line of protists. ... Possible classes Polycystinea Acantharea Taxopodea Radiolaria are amoeboid protozoa that produce intricate mineral skeletons, typically with a central capsule dividing the cell into inner and outer portions, called endoplasm and ectoplasm. ... Orders Allogromiida Carterinida Fusulinida - extinct Globigerinida Involutinida - extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis    Xenophyophorea    Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ... The Cercozoa are a group of protists, including most amoeboids and flagellates that feed by means of filose pseudopods. ... The Archaeplastida are a major line of eukaryotes, comprising the land plants, green and red algae, and a small group called the glaucophytes. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae Red algae (Rhodophyta, pronounced /ˈrəʊdÉ™(ÊŠ)ËŒfʌɪtÉ™/) are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Possible classes Glaucocystis Cyanophora Gloeochaete The glaucophytes (Glaucophyta Skuja), also referred to as glaucocystophytes or glaucocystids, are a tiny group of freshwater algae. ... Subgroups Mycetozoa(slime moulds) Archamoebae    Pelobiontida    Entamoebida Gymnamoebia Various others The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. ... The opisthokonts are a broad group of eukaryotes, including both the animals and fungi, together with a few sorts of protists. ... This chart shows concisely the most common way in which the International Phonetic Alphabet (IPA) is applied to represent the English language. ... Note: This page or section contains IPA phonetic symbols in Unicode. ... Note: This page or section contains IPA phonetic symbols in Unicode. ... “Life on Earth” redirects here. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative phylogeny Unikonta Opisthokonta Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ... Ernst Haeckels presentation of a three-kingdom system (Plantae, Protista, Animalia) in his 1866 Generelle Morphologie der Organismen). ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... For other uses, see Animal (disambiguation). ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular land plants (bryophytes) Marchantiophyta—liverworts Anthocerotophyta—hornworts Bryophyta—mosses †Horneophytopsida Vascular plants (tracheophytes) †Rhyniophyta—rhyniophytes †Zosterophyllophyta—zosterophylls Lycopodiophyta—clubmosses †Trimerophytophyta—trimerophytes Pteridophyta—ferns and horsetails Ophioglossophyta - adders-tongues Seed plants (spermatophytes) †Pteridospermatophyta—seed ferns Pinophyta—conifers Cycadophyta—cycads Ginkgophyta—ginkgo... Ernst Haeckels presentation of a three-kingdom system (Plantae, Protista, Animalia) in his 1866 Generelle Morphologie der Organismen). ... In phylogenetics, a grouping of organisms is said to be paraphyletic (Greek para = near and phyle = race) if all the members of the group have a common ancestor, but the group does not include all the descendants of the most recent common ancestor of all group members. ... In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ... A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... “Life on Earth” redirects here. ... Ernst Haeckel. ... 1866 (MDCCCLXVI) is a common year starting on Monday of the Gregorian calendar or a common year starting on Wednesday of the 12-day-slower Julian calendar. ...


Protists were traditionally subdivided into several groups based on similarities to the "higher" kingdoms: the one-celled animal-like protozoa, the plant-like protophyta (mostly one-celled algae), and the fungus-like slime molds and water molds. Because these groups often overlap, they have been replaced by phylogenetic-based classifications. However, they are still useful as informal names for describing the morphology and ecology of protists. A cluster of Escherichia coli bacteria magnified 10,000 times. ... Wikisource has an original article from the 1911 Encyclopædia Britannica about: Protozoa Protozoa (in Greek proto = first and zoa = animals) are single-celled eukaryotes (organisms whose cells have nuclei) that commonly show characteristics usually associated with animals, most notably mobility and heterotrophy. ... The thallophytes are a polyphyletic group of non-mobile organisms traditionally described as relatively simple plants or lower plants with undifferentiated bodies (thalli). ... A cluster of Escherichia coli bacteria magnified 10,000 times. ... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Typical orders Protostelia    Protosteliida Myxogastria    Liceida    Echinosteliida    Trichiida    Stemonitida    Physarida Dictyostelia    Dictyosteliida Slime moulds are peculiar protists that normally take the form of amoebae, but under certain conditions develop fruiting bodies that release spores, superficially similar to the sporangia of fungi. ... Orders Lagenidiales Leptomitales Peronosporales Pythiales Rhipidiales Saprolegniales Sclerosporales Water moulds or Oomycetes are a group of filamentous protists, physically resembling fungi. ... A phylogeny (or phylogenesis) is the origin and evolution of a set of organisms, usually of a species. ... Classification may refer to: Taxonomic classification See also class (philosophy) Statistical classification Security classification Hint: Language use may refer to a taxonomic classification that is used for statistical purposes also as a statistical classification (like International Statistical Classification of Diseases and Related Health Problems). ... The term morphology in biology refers to the outward appearance (shape, structure, colour, pattern) of an organism or taxon and its component parts. ... This article or section does not cite any references or sources. ...


At one time, the non-nucleated bacteria were also considered protists under the three-kingdom system of Animalia (comprising the many-celled animals or metazoans), Plantae (which then included fungi as well as green land plants), and Protista (which included everything else, except viruses). However, most current textbooks treat bacteria (and the newly-discovered archaea) as either a separate kingdom or domain. There are two meanings of the word nucleus in biology: The cell nucleus is an organelle within an eukaryotic cell. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... Phyla Subkingdom Parazoa Porifera (sponges) Subkingdom Agnotozoa Placozoa Orthonectida Rhombozoa Subkingdom Metazoa Radiata Cnidaria Ctenophora - Comb jellies Bilateria Protostomia Acoelomorpha Platyhelminthes - Flatworms Nemertina - Ribbon worms Gastrotricha Gnathostomulida - Jawed worms Micrognathozoa Rotifera - Rotifers Acanthocephala Priapulida Kinorhyncha Loricifera Entoprocta Nematoda - Roundworms Nematomorpha - Horsehair worms Cycliophora Mollusca - Mollusks Sipuncula - Peanut worms Annelida - Segmented... Divisions Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adders-tongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants The embryophytes are the most familiar... Groups I: dsDNA viruses II: ssDNA viruses III: dsRNA viruses IV: (+)ssRNA viruses V: (-)ssRNA viruses VI: ssRNA-RT viruses VII: dsDNA-RT viruses A virus (from the Latin noun virus, meaning toxin or poison) is a microscopic particle (ranging in size from 20 - 300 nm) that can infect the... Phyla Crenarchaeota Euryarchaeota Korarchaeota Nanoarchaeota Archaea are a major division of microorganisms. ... In biology, a domain (also superregnum, superkingdom, or empire) is the top-level grouping of organisms in scientific classification, higher than a kingdom. ...

Contents

Obtaining nutrients

Protists obtain nutrients and digest nutrients in a complex acquirement and assimilation system. Most protists also feed on bacteria. Protists acquire their food material through internal digestion. They extend their cell wall and cell membrane around the food material to form a food vacuole in exocytosis and cytoplasmic metabolic ingestion, also sometimes pinocytosis. The food vacuole is used to paralyze the food material. It contains a grana-like texture that can support the use of toxins to paralyze organisms. The food vacuole extends from the prey to inside the protist's cytoplasm and the food material basically falls through the vacuole through gravity (similar to tropism in plants) and enters the cell. Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... A cell wall is a fairly rigid layer surrounding a cell, located external to the cell membrane, that provides the cell with structural support, protection, and a filtering mechanism. ... The cell membrane (also called the plasma membrane, plasmalemma or phospholipid bilayer) is a semipermeable lipid bilayer common to all living cells. ... Schematic of typical animal cell, showing subcellular components. ... This page is currently under construction. ... Phagocytosis is a form of endocytosis wherein large particles are enveloped by the cell membrane of a (usually larger) cell and internalized to form a phagosome, or food vacuole. ... Pinocytosis or cell drinking is one of three forms of endocytosis, a cellular process that is used to take up smaller particles in cell by splitting in small particles , and forms vesicles which then merge with lysosomes to hydrolyze (hydrolytic enyzmes) to break down the particles. ... Grana may refer to: grana (cheese), a generic name for Italian granular cheeses such as Grana Padano and Parmigiano Reggiano granum, a term in biology Grana (AT), a commune in Piedmont, Italy Grana, Sachsen-Anhalt, a municipality in Sachsen-Anhalt, Germany Grana (Galicia), a municipality in Spain, also known as... This article or section does not cite any references or sources. ... It has been suggested that Cytoplast be merged into this article or section. ... It has been suggested that chemotropism be merged into this article or section. ...


A protist cell generally has an intestinal tract that is considerably small and is around the Golgi Apparatus. Once the food is into the cell, it can be used by ribosomes in the rough endoplasmic reticulum to be manufactured into proteins. For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... Diagram of the endomembrane system in a typical eukaryote cell Micrograph of Golgi apparatus, visible as a stack of semicircular black rings near the bottom. ... Figure 1: Ribosome structure indicating small subunit (A) and large subunit (B). ... The endoplasmic reticulum or ER (endoplasmic means within the cytoplasm, reticulum means little net) is an organelle found in all eukaryotic cells. ...


Nutrition in some different types of protists is variable. In flagellates, for example, filter feeding may sometimes occur where the flagella find the prey. In other multicellular protists, elements like nitrogen and oxygen is acquired by constant beating of the flagella. Protists often occur in hydrophilic conditions and thus have large amounts of oxygen within them, which is necessary for them to conduct respiration and photosynthesis to desirable levels. Filter feeders (also known as suspension feeders) are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized structure, such as the baleen of baleen whales. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Standard atomic weight 15. ... A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... // In animal physiology, respiration is the transport of oxygen from the ambient air to the tissue cells and the transport of carbon dioxide in the opposite direction. ... The leaf is the primary site of photosynthesis in plants. ...


Organization

Protozoa, the animal-like protists

Protozoa are mostly single-celled, motile protists that feed by phagocytosis, though there are numerous exceptions. They are usually only 0.01–0.5 mm in size, generally too small to be seen without magnification. Protozoa are grouped by method of locomotion into: Motile A term to describe Intelligent Mobile Applications. ... Phagocytosis is a form of endocytosis wherein large particles are enveloped by the cell membrane of a (usually larger) cell and internalized to form a phagosome, or food vacuole. ... Magnification is the process of enlarging something only in appearance, not physical size. ... In a general sense, locomotion simply means active movement or travel, applying not just to biological individuals. ...

Flagellates with long flagella e.g., Euglena
Amoeboids with transient pseudopodia e.g., Amoeba
Ciliates with multiple, short cilia e.g., Paramecium
Sporozoa non-motile parasites; some can form spores e.g., Toxoplasma

Flagellata from Ernst Haeckels Artforms of Nature, 1904 Parasitic excavate (Giardia lamblia) Green alga (Chlamydomonas) Flagellates are cells with one or more whip-like organelles called flagella. ... // A flagellum (plural: flagella) is a long, slender projection from the cell body, composed of microtubules and surrounded by the plasma membrane. ... Hey Euglena is a common Euglenophyte protist, typical of the euglenids, and commonly found in nutrient-rich freshwater, with a few marine species. ... Amoeba (Chaos diffluens) Foraminiferan (Ammonia tepida) Heliozoan (Actinophrys sol) Amoeboids are cells that move or feed by means of temporary projections, called pseudopods (false feet). ... Pseudopods or pseudopodia (false feet) are temporary projections of eukaryotic cells. ... Alternate meanings: Amoeboid, Amoebozoa For other uses, see Amoeba (disambiguation). ... Classes Karyorelictea Heterotrichea Spirotrichea Litostomatea Phyllopharyngea Nassophorea Colpodea Prostomatea Oligohymenophorea Plagiopylea See text for subclasses. ... cross-section of two motile cilia, showing the 9+2 structure A cilium (plural cilia) or undulipodium (pl. ... This article does not cite its references or sources. ... Classes & Subclasses Aconoidasida Haemosporasina Piroplasmasina Blastocystea Conoidasida Coccidiasina Gregarinasina The Apicomplexa are a large group of protozoa, characterized by the presence of a unique organelle called an apical complex. ... Binomial name Toxoplasma gondi (Nicolle & Manceaux), 1908 Toxoplasma gondii is a species of parasitic protozoa, belonging to the Apicomplexa, that can cause the disease toxoplasmosis in humans. ...

Algae, the plant-like protists

They include many single-celled organisms that are also considered protozoa, such as Euglena, which many believe have acquired chloroplasts through secondary endosymbiosis. Others are non-motile, and some (called seaweeds) are truly multicellular, including members of the following groups: Hey Euglena is a common Euglenophyte protist, typical of the euglenids, and commonly found in nutrient-rich freshwater, with a few marine species. ... Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... An endosymbiont (also known as intracellular symbiont) is any organism that lives within cells of another organism, i. ... Ascophyllum nodosum exposed to the sun in Nova Scotia, Canada Dead Mans Fingers (Codium fragile) off Massachusetts coast For the Marine Biology Summer internship Marine Algae by Friday Harbor Laboratories, see; Marine Algae For the band, see; Seaweed (band) For the rock musician, see; Seaweed (musician) Seaweeds are any...

Chlorophytes green algae, are related to higher plants e.g., Ulva
Rhodophytes red algae e.g., Porphyra
Heterokontophytes brown algae, diatoms, etc. e.g., Macrocystis

The green and red algae, along with a small group called the glaucophytes, appear to be close relatives of other plants, and so some authors treat them as Plantae despite their simple organization. Most other types of algae, however, developed separately. They include the haptophytes, cryptomonads, dinoflagellates, euglenids, and chlorarachniophytes, all of which have also been considered protozoans. Divisions Chlorophyta Charophyta Streptophytina (Subdivision) The green algae are the large group of algae from which the embryophytes (higher plants) emerged. ... Species Ulva lactuca Ulva pertusa Ulva fasciata Ulva rigida Ulva pertusa Ulva linza and more at algaeBASE The sea lettuces comprise the genus Ulva, a group of edible green algae widely distributed along the coasts of the worlds oceans. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae Red algae (Rhodophyta, pronounced /ˈrəʊdÉ™(ÊŠ)ËŒfʌɪtÉ™/) are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Porphyra is a genus of red algae. ... Typical classes Colored groups Chrysophyceae (golden algae) Synurophyceae Actinochrysophyceae (axodines) Pelagophyceae Phaeothamniophyceae Bacillariophyceae (diatoms) Bolidophyceae Raphidophyceae Eustigmatophyceae Xanthophyceae (yellow-green algae) Phaeophyceae (brown algae) Colorless groups Oomycetes (water moulds) Hypochytridiomycetes Bicosoecea Labyrinthulomycetes (slime nets) Opalinea Proteromonadea The heterokonts or stramenopiles are a major line of eukaryotes containing about 10,500... Species Macrocystis pyrifera Macrocystis is a genus of kelp. ... The glaucophytes, also referred to as glaucocystophytes or glaucocystids, are a tiny group of freshwater algae. ... Orders Class Pavlovophyceae    Pavlovales Class Prymnesiophyceae    Prymnesiales    Phaeocystales    Isochrysidales    Coccolithales The haptophytes, classed either as the Prymnesiophyta or Haptophyta, are a group of algae. ... Typical genera Campylomonas Chilomonas Chroomonas Cryptomonas Falcomonas Geminigera Goniomonas Guillardia Hemiselmis Plagioselmis Proteomonas Storeatula Rhodomonas Teleaulax The cryptomonads are a small group of flagellates, most of which have chloroplasts. ... Classes Dinophyceae Noctiluciphyceae Syndiniophyceae The dinoflagellates are a large group of flagellate protists. ... Major groups Phototrophs    Euglenales    Eutreptiales Osmotrophs    Rhabdomonadales Phagotrophs    ?Heteronematales    ?Sphenomonadales The euglenids (also spelled euglenoids) are one of the best-known groups of flagellates, commonly found in freshwater especially when it is rich in organic materials, with a few marine and endosymbiotic members. ... Genera Chlorarachnion Gymnochlora Lotharella Cryptochlora Chlorarachniophytes are a small group of algae occasionally found in tropical oceans. ...


Note some protozoa host endosymbiotic algae, as in Paramecium bursaria or radiolarians, that provide them with energy but are not integrated into the cell. Binomial name Paramecium bursaria (Ehr. ... Possible classes Polycystinea Acantharea Taxopodea Radiolaria are amoeboid protozoa that produce intricate mineral skeletons, typically with a central capsule dividing the cell into inner and outer portions, called endoplasm and ectoplasm. ...


Fungus-like protists

Various organisms with a protist-level organization were originally treated as fungi, because they produce sporangia. These include chytrids, slime moulds, water moulds, and Labyrinthulomycetes. Of these, the chytrids are now known to be related to other fungi and are usually classified with them. The others are now placed among the heterokonts (which have cellulose rather than chitin walls) and the Amoebozoa (which do not have cell walls). A sporangium (pl. ... Orders Chytridiales Spizellomycetales Monoblepharidales Blastocladiales Neocallimasticales Chytridiomycota is a division of the Fungi kingdom and contains only one class, Chytridiomycetes. ... Typical orders Protostelia    Protosteliida Myxogastria    Liceida    Echinosteliida    Trichiida    Stemonitida    Physarida Dictyostelia    Dictyosteliida Slime mould (or slime mold) is a broad term often referring to roughly 6 groups of Eukaryotes. ... Orders Lagenidiales Leptomitales Peronosporales Pythiales Rhipidiales Saprolegniales Sclerosporales Water moulds or Oomycetes are a group of filamentous protists, physically resembling fungi. ... Genera Labyrinthulids    Labyrinthula Thraustochytrids    Aplanochytrium    Labyrinthuloides    Japonochytrium    Schizochytrium    Thraustochytrium    Ulkenia Diplophryids    Diplophrys The Labyrinthulomycetes are a group of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. ... Typical classes Colored groups Chrysophyceae (golden algae) Synurophyceae Actinochrysophyceae (axodines) Pelagophyceae Phaeothamniophyceae Bacillariophyceae (diatoms) Bolidophyceae Raphidophyceae Eustigmatophyceae Xanthophyceae (yellow-green algae) Phaeophyceae (brown algae) Colorless groups Oomycetes (water moulds) Hypochytridiomycetes Bicosoecea Labyrinthulomycetes (slime nets) Opalinea Proteromonadea The heterokonts or stramenopiles are a major line of eukaryotes containing about 10,500... Subgroups Mycetozoa(slime moulds) Archamoebae    Pelobiontida    Entamoebida Gymnamoebia Various others The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. ...


The term Protoctista

During the latter 20th century, the terms Protista, protist and protistan were increasingly used by biological scientists and laymen alike. Groups devoted to protistology emerged, while protozoology seemed to fade as an intellectual construct. In more recent years, however, the terms Protoctista, protoctist and protoctistan have been championed by some scholars in microbiology and micropaleontology. For example, the 50-volume Treatise on Invertebrate Paleontology -- eager to fill in the gaps left by vertebrate paleontology -- has moved from its 1953 (and onwards) use of Protista to the 21st-century use of Protoctista. So a Protist-Protoctist debate would seem to be inevitable. This article does not cite any references or sources. ... Micropaleontology, the study of microfossils, is a branch of paleontology. ... The Treatise on Invertebrate Paleontology, published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 authors, and covering every phylum, class, order, family, and genus of fossil and extant (still living) invertebrate... Vertebrate paleontology seeks to discover the behavior, reproduction and appearance of extinct spined animals, through the study of their fossilized remains. ...


The taxonomic category Protoctista was first coined by an English biologist, John Hogg, in an article entitled On the distinctions between a plant and an animal, and on a fourth kingdom of nature (1860). In this article, Hogg argued that the term Protoctist should be used to include "both the Protophyta ... and Protozoa". Therefore, he said, there should be a "fourth kingdom of nature" in addition to the then-traditional kingdoms of plants, animals and minerals. For nearly a century, however, his ideas were eclipsed by those of Haeckel, the reputed founder of protistology. John Joseph Hogg (born 19 March 1949), Australian politician, has been a member of the Australian Senate for the state of Queensland since July 1996, representing the Australian Labor Party. ...


Herbert F. Copeland resurrected Hogg's label in his article, Progress report on basic classification (1947). Arguing that "Protoctista" literally meant "first established beings", Copeland complained that Haeckel's term included anucleated microbes such as bacteria. Copeland's term did not. Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ...


Indeed, Copeland's term even included nucleated eukaryotes such as brown and red algae -- but not the green algae, which he placed with the other green plants. Copeland further elaborated on his taxonomic proposal in his 1956 book, Classification of Lower Organisms (Palo Alto, California: Pacific Books). The eukaryotic cell nucleus. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative phylogeny Unikonta Opisthokonta Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ... The Heterokontophyta (Phaeophyta or brown algae, singular: brown alga) is a large group of mostly marine multicellular algae, including many seaweeds of colder Northern Hemisphere waters. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae The red algae (Rhodophyta, IPA: , from Greek: (rhodon) = rose + (phyton) = plant, thus red plant) are a large group, about 5000 - 6000 species [1] of mostly multicellular, marine algae, including many notable seaweeds. ... Divisions Chlorophyta Charophyta Green algae are microscopic protists; found in all aquatic environments, including marine, freshwater and brackish water. ... Divisions Green algae land plants (embryophytes) non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses vascular plants (tracheophytes) seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongue ferns seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta...


Phylogenetic classifications

The taxonomy of protists is still changing. Newer classifications[1] attempt to present monophyletic groups based on ultrastructure, biochemistry, and genetics. Because the protists as a whole are paraphyletic, such systems often split up or abandon the kingdom, instead treating the protist groups as separate lines of eukaryotes. The recent scheme by Adl et al. (2005)[2] is an example that does not bother with ranks (phylum, class, etc.). In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ... Ultrastructure is the detailed structure of a biological specimen, such as a cell, tissue, or organ, that can be by electron microscopy. ... Biochemistry is the study of the chemical processes and transformations in living organisms. ... DNA, the molecular basis for inheritance. ...


Some of the main groups of protists, which may be treated as phyla, are listed in the taxobox at right. Most have been established as monophyletic, though for some this is still uncertain; for instance the metamonads, which may be paraphyletic to other excavates, and the Chromista, which may be paraphyletic to the alveolates (see chromalveolates). Various smaller groups of protists also existed; these are listed under the traditional categories, linked to above. The excavates are a major line of protists, often known as Excavata. ... Phyla Heterokontophyta Haptophyta Cryptophyta The Chromista are a eukaryotic supergroup, which may be treated as a separate kingdom or included among the Protista. ... The alveolates are a major line of protists. ... Phyla Heterokontophyta Haptophyta Cryptophyta Alveolata Ciliophora Apicomplexa Dinoflagellata Chromalveolata is a eukaryote supergroup first proposed by Thomas Cavalier-Smith as a refinement of his kingdom Chromista, which was first proposed in 1981. ...


For more discussion of relationships between different protists and their evolution, see eukaryote or the articles referenced below. Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative phylogeny Unikonta Opisthokonta Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ...


References

  1. ^ Cavalier-Smith, T.; Chao, E. E. Y. (2003). "Phylogeny and classification of phylum Cercozoa (Protozoa)". Protist 154 (3–4): 341–358. DOI:10.1078/143446103322454112. 
  2. ^ Adl, S. M.; et al. (2005). "The new higher level classification of eukaryotes with emphasis on the taxonomy of protists". Journal of Eukaryotic Microbiology 52 (5): 399–451. DOI:10.1111/j.1550-7408.2005.00053.x. 
Wikimedia Commons has media related to:
Protista

Thomas Cavalier-Smith is a professor of evolutionary biology at the University of Oxford, and is winner of the International Prize for Biology 2004 and one of the most notable researchers concerning the relationships, development, and classification of living things. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Image File history File links Commons-logo. ...

Other references

Marguilis, L., Corliss, J.O., Melkonian, M.,and Chapman, D.J. (Editors) 1990. Handbook of Protoctista. Jones and Bartlett , Boston. ISBN 0-86720-052-9


  Results from FactBites:
 
Protist - Wikivisual (631 words)
Protists (IPA: [ˈprəʊ.tɪst] or [ˈpro.tɪst]) are a heterogeneous group of organisms, comprising those eukaryotes that are not animals, plants, or fungi.
The protists are a paraphyletic grade, rather than a natural (monophyletic) group, and do not have much in common besides a relatively simple organization (unicellular, or multicellular without highly specialized tissues).
Protists were traditionally (for the last 150 years) subdivided into several groups based on similarities to the higher kingdoms: the animal-like protozoa, the plant-like algae, and the fungus-like slime molds and water molds.
BioEd Online Slides: protist, protozoan, plants, kingdom, algae (1579 words)
Protists form a broad base across the bottom of the food chain, and they supply approximately one-half of the world's oxygen (unicellular algae compose a large portion of the world's phytoplankton).
Protists, along with bacteria and fungi, are responsible for decomposing and recycling nutrients.
Animal-like protists are responsible for diseases such as malaria, amoebic dysentery, toxoplasmosis, African Sleeping Sickness and Giardiasis in humans.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m