SUMMARY / RELATED TOPICS

Flagellate

A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word flagellate describes a particular construction characteristic of many prokaryotes and eukaryotes and their means of motion; the term presently does not imply any specific relationship or classification of the organisms that possess flagellae. However, the term "flagellate" is included in other terms. Flagella are supported by microtubules in a characteristic arrangement, with nine fused pairs surrounding two central singlets; these arise from a basal body. In some flagellates, flagella direct food into a cytostome or mouth, where food is ingested. Flagella support hairs, called mastigonemes, or contain rods, their ultrastructure plays an important role in classifying eukaryotes. Among protoctists and microscopic animals, a flagellate is an organism with one or more flagella; some cells in other animals may be flagellate, for instance the spermatozoa of most animal phyla. Flowering plants do not produce flagellate cells, but ferns, green algae, some gymnosperms and related plants do so.

Most fungi do not produce cells with flagellae, but the primitive fungal chytrids do. Many protists take the form of single-celled flagellates. Flagella are used for propulsion, they may be used to create a current that brings in food. In most such organisms, one or more flagella are located at or near the anterior of the cell, e.g. Euglena. There is one directed forwards and one trailing behind. Among animals, which are part of a group called the opisthokonts, there is a single posterior flagellum, they are from the phylum Mastigophora. They can cause diseases and are heterotrophic, they reproduce by binary fission. They spend most of their existence feeding. Many parasites that affect human health or economy are flagellates. Flagellates are the major consumers of primary and secondary production in aquatic ecosystems - consuming bacteria and other protists. An overview of the occurrence of flagellated cells in eukaryote groups, as specialized cells of multicellular organisms or as life cycle stages, is given below: Archaeplastida: most green algae, pteridophytes, some gymnosperms Stramenopiles: centric diatoms, brown algae, hyphochytrids, labyrinthulomycetes, some chrysophytes, some xanthophytes, eustigmatophytes Alveolata: some apicomplexans Rhizaria: some radiolarians, foraminiferans Cercozoa: plasmodiophoromycetes, chlorarachniophytes Amoebozoa: myxogastrids Opisthokonta: most metazoans, chytrid fungi Excavata: some acrasids In older classifications, flagellated protozoa were grouped in Flagellata, sometimes divided in Phytoflagellata and Zooflagellata.

They were sometimes grouped with Sarcodina in the group Sarcomastigophora. The autotrophic flagellates were grouped to the botanical schemes used for the corresponding algae groups; the colourless flagellates were customary grouped in three groups artificial: Protomastigineae, in which absorption of food-particles in holozoic nutrition occurs at a localised point of the cell surface at a cytostome, although many groups were saprophytes. Presently, these groups are known to be polyphyletic. In modern classifications of the protists, the principal flagellated taxa are placed in the following eukaryote groups, which include non-flagellated forms: Archaeplastida: volvocids, glaucophytes Stramenopiles: bicosoecids, opalines, most chrysophytes, part of xanthophytes, raphidophytes/chloromonads, silicoflagellates, pedinellids Alveolata: dinoflagellates, Colpodella Rhizaria Cercozoa: cercomonads, thaumatomonads, cryomonads, heliomonads/dimorphids, ebriids Amoebozoa: Multicilia, some archamoebae Opisthokonta: choanoflagellates Excavata Discoba: jakobids, euglenids, some heteroloboseans Metamonada: diplomonads, Preaxostyla/anaeromonads, parabasalids Eukaryota incertae sedis: haptophytes, kathablepharids, collodictyonids/diphylleids and about a hundred generaAlthough the taxonomic group Flagellata was abandoned, the term "flagellate" is still used as the description of a level of organization and as an ecological functional group.

Another term used is "monadoid", from monad. as in Monas, Cryptomonas

Epsilon Leporis

Epsilon Leporis is a third-magnitude star in the southern constellation Lepus. The apparent visual magnitude of +3.166 places it third in brightness among the stars in this constellation. Based upon parallax measurements, it is located at a distance of around 213 light-years from Earth; this is an evolved giant star with a stellar classification of K4 III that has expanded to 40 times the Sun's radius. It is about 1.72 billion years old and has 1.70 times the mass of the Sun, with a luminosity 372 times as great. The outer atmosphere is cooler than the Sun's with an effective temperature of 4,131 K, giving it the orange hue of a K-type star. In terms of its composition, this star shows a similar abundance of elements other than hydrogen and helium to the Sun; the envelope of this star is undergoing oscillations that show up as changes in the star's radial velocity. Over long durations these follow a linear trend, in combination with shorter period oscillations occurring over a few days; these oscillations are unlikely to be the result of rotational module as that would imply a high rotation rate, which would display itself through strong X-ray emissions.

Instead, they may be the result of solar-like and Mira-like oscillations

Komano Station

Komano Station is a railway station in the city of Kaizu, Gifu Prefecture, operated by the private railway operator Yōrō Railway. Komano Station is a station on the Yōrō Line, is located 19.8 rail kilometers from the opposing terminus of the line at Kuwana. Komano Station has one ground-level side platform and one ground-level island platform connected by a level crossing; the station is unattended. Komano Station opened on April 27, 1919. In fiscal 2015, the station was used by an average of 880 passengers daily. Shioryama Junior High School National Route 258 List of Railway Stations in Japan Media related to Komano Station at Wikimedia Commons Official website