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Opisthokont

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39-434: The opisthokonts (from Ancient Greek ὀπίσθιος ( opísthios )  'rear, posterior' and κοντός ( kontós )  'pole, i.e. flagellum ') are a broad group of eukaryotes , including both the animal and fungus kingdoms . The opisthokonts, previously called the "Fungi/Metazoa group", are generally recognized as a clade . Opisthokonts together with Apusomonadida and Breviata comprise

78-467: A mitochondrial genome and most components of the electron transport chain . Of the citric acid cycle enzymes, which are present in the mitochondria in other organisms, only two are present in Pygsuia : fumarase and succinate dehydrogenase . In contrast, Lenisia cells contain multiple MROs with cristae . Breviatea is a clade of basal eukaryotes . They are closely related to the apusomonads and

117-537: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in

156-472: A lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and

195-419: A lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in

234-543: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment

273-671: A separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek , and Koine may be classified as Ancient Greek in a wider sense. There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek

312-609: A standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about the Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c.  300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as

351-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and

390-556: Is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in the epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of

429-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected

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468-644: Is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to

507-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in

546-406: Is to plants, because opisthokonts have a triple fusion of carbamoyl phosphate synthetase , dihydroorotase , and aspartate carbamoyltransferase that is not present in plants, and plants have a fusion of thymidylate synthase and dihydrofolate reductase not present in the opisthokonts. Animals and fungi are also more closely related to amoebas than to plants, and plants are more closely related to

585-745: The Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as the Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect

624-505: The Obazoa clade. They likely do not possess vinculin proteins. Their metabolism relies on fermentative production of ATP as an adaptation to their low-oxygen environment. The lineage emerged roughly one billion years ago, at a time when the oxygen content of the Earth's oceans was low, and they thus developed anaerobic lifestyles. Together with Apusomonads , they are the closest relatives of

663-615: The Opisthokonta supergroup, and together they compose the larger clade Obazoa , which is the sister group to Amoebozoa . Within Breviatea, the four known species are distributed into smaller clades of two species each: one uniting Breviata with Subulatomonas , and one uniting Lenisia with Pygsuia . CRuMs Amoebozoa Breviata anathema Subulatomonas tetraspora Lenisia limosa Pygsuia biforma Apusomonadida Holozoa Holomycota The class Breviatea

702-502: The Opisthokonts , a group that includes animals and fungi. Mitochondrion-related organelles (MROs) are organelles that evolved from a degradation of ancestral, fully functional mitochondria . Among Breviatea, MROs are present in Pygsuia , Breviata and Subulatomonas . In the cells of Pygsuia , for which the complete transcriptome is known, there is a single smooth MRO that lacks

741-717: The SAR supergroup of protists than to animals or fungi. Animals and fungi are both heterotrophs , unlike plants, and while fungi are sessile like plants, there are also sessile animals. Cavalier-Smith and Stechmann argue that the uniciliate eukaryotes such as opisthokonts and Amoebozoa , collectively called unikonts , split off from the other biciliate eukaryotes, called bikonts , shortly after they evolved . Opisthokonts are divided into Holomycota or Nucletmycea (fungi and all organisms more closely related to fungi than to animals) and Holozoa (animals and all organisms more closely related to animals than to fungi); no opisthokonts basal to

780-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)

819-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):

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858-490: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from

897-681: The Classical period of ancient Greek. (The second line is the IPA , the third is transliterated into the Latin alphabet using a modern version of the Erasmian scheme .) Ὅτι [hóti Hóti μὲν men mèn ὑμεῖς, hyːmêːs hūmeîs,   Breviatea Breviatea , commonly known as breviate amoebae , are a group of free-living, amitochondriate protists with uncertain phylogenetic position. They are biflagellate , and can live in anaerobic (oxygen-free) environments. They are currently placed in

936-1011: The Holomycota/Holozoa split have yet been identified. The Opisthokonts was largely resolved by Torriella et al. Holomycota and Holozoa are composed of the following groups. The following phylogenetic tree indicates the evolutionary relationships between the different opisthokont lineages, and the time divergence of the clades in millions of years ago (Mya). Amoebozoa [REDACTED] Breviatea [REDACTED] Apusomonadida [REDACTED] Nucleariae [REDACTED] True Fungi [REDACTED] Aphelida Rozellida [REDACTED] Microsporidia [REDACTED] Ichthyosporea [REDACTED] Corallochytrium [REDACTED] Syssomonas [REDACTED] Tunicaraptor Filasterea [REDACTED] Choanoflagellatea [REDACTED] Metazoa [REDACTED] Ancient Greek language Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes

975-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has

1014-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in

1053-438: The center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West

1092-611: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of

1131-663: The forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c.  1400–1200 BC ), Dark Ages ( c.  1200–800 BC ), the Archaic or Epic period ( c.  800–500 BC ), and the Classical period ( c.  500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been

1170-417: The fungi. Opisthokont characteristics include synthesis of extracellular chitin in exoskeleton, cyst/spore wall, or cell wall of filamentous growth and hyphae; the extracellular digestion of substrates with osmotrophic absorption of nutrients; and other cell biosynthetic and metabolic pathways. Genera at the base of each clade are amoeboid and phagotrophic . The close relationship between animals and fungi

1209-556: The historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from

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1248-472: The historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at the time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to

1287-492: The larger clade Obazoa . A common characteristic of opisthokonts is that flagellate cells, such as the sperm of most animals and the spores of the chytrid fungi , propel themselves with a single posterior flagellum. It is this feature that gives the group its name. In contrast, flagellate cells in other eukaryote groups propel themselves with one or more anterior flagella . Flagellate cells however have been secondarily lost in some opisthokont groups, including most of

1326-499: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which

1365-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c.  1450 BC ) are in

1404-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies

1443-475: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,

1482-462: Was created in 2004 by British protozoologist Thomas Cavalier-Smith to group a problematic taxon previously known as ‘Mastigamoeba invertens’ . This organism, initially classified in the Archamoebae within phylum Amoebozoa , appeared to strongly diverge in phylogenetic trees based on ribosomal RNA and had a structure very different from other Archamoebae. Because of these results, ‘M. invertens’

1521-482: Was suggested by Thomas Cavalier-Smith in 1987, who used the informal name opisthokonta (the formal name has been used for the chytrids by Copeland in 1956), and was supported by later genetic studies. Early phylogenies placed fungi near the plants and other groups that have mitochondria with flat cristae , but this character varies. More recently, it has been said that holozoa (animals) and holomycota (fungi) are much more closely related to each other than either

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