- Ommatidium
File Ommatidie.JPG thumb right Ommatidium A cornea, B crystalline cone, C & D pigment cells, E rhabdom, F ? cells, G membrana fenestrata, H optic nerve File Compound eye2.jpg thumb right Ommatidia The compound eye s of insect s, mantis shrimp and millipede s ref cite journal author Carsten H.G. M ller, Andy Sombke & J rg Rosenberg year 2007 title The fine structure of the eyes of some bristly millipedes Penicillata, Diplopoda additional support for the homology of mandibulate ommatidia journal Arthropod Structure & Development volume 36 issue 4 pages 463 476 doi 10.1016 j.asd.2007.09.002 pmid 18089122 ref are composed of units called ommatidia singular ommatidium . An ommatidium contains a cluster of photoreceptor cell s surrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea . Each ommatidium is innervated by one axon and thus provides the brain with pixel one picture element . The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of insect and ranges from just a handful in the primitive Archaeognatha and Thysanura to many tens of thousand in larger Anisoptera ... of the ommatidium. The inner 90 of the ommatidium contains 6 to 9 in the case of some butterflies ref ... Eye, Journal of Experimental Biology, 2008 ref . These R cells tightly pack the ommatidium. The portion of the R cells at the central axis of the ommatidium collectively form a light guide, a transparent ... rhabdomeres . This has required the rewiring of the eye such that each ommatidium now has seven ... entering at an angle from being detected by the ommatidium it entered or by any of the six neighboring ommatidia, six pigment cells are present. The pigment cells line the outside of each ommatidium. Each ... ommatidium. In many species, in low light situations, the pigment is withdrawn, so that light ... anatomy Category Insect anatomy de Ommatidium es Omatidio fa nl Ommatidium pl Omatidium ... more details
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- Sevenless
Refimprove date October 2008 sevenless sev is a gene in Drosophila melanogaster that encodes a receptor tyrosine kinase protein essential to the development of R7 cells in the Drosophila embryonic eye ref http www.ncbi.nlm.nih.gov bookshelf br.fcgi?book mcb&part A5803, A5808 ref .The drosophila ommatidium contains 8 distinct retinula or R cells, each of which has a different spectral sensitivity. The R7 photo receptor, located in each of several ommatidium in the fly s compound eye, is used to detect ultraviolet light ref cite book last1 Smith first1 Christopher U.M. title Elements of Molecular Neurobiology url http www.wiley.com WileyCDA WileyTitle productCd 0471560383.html year 2002 origyear 1989 publisher Oxford Journals isbn 0471560383 pages 450 451 chapter 19.5 Morphogenesis in the Drosophila eye chapterurl http books.google.com books?id pHZsSXDcesC&lpg PA451&ots JwyO 6dRaK&dq retinula 20sevenless&pg PA451 v onepage&q retinula 20sevenless&f false ref . The R8 photo receptor contains an activator of the RTK receptor tyrosine kinase for on a precursor R7 cell, called the bride of sevenless BOSS . The binding of BOSS to sevenless stimulates a complex series of reactions involving the RTK sevenless , MAP kinases, Ras and many more molecules to differentiate that precursor R7 photo receptor to a fully functional R7 photo receptor that can see UV light. Much of this knowledge was gained by examining flies with a mutant sevenless but still produced a fully functional R7 photoreceptor when a dominant Ras was injected into the mutant R7 precursor without the normal sevenless. References reflist Category Drosophilidae ... more details
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- Polyphaga
tubule s of the normal type, a cone ommatidium with open rhabdom , and lack of functional spiracle ... more details
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- Book:Eye
nerve palsy Odd eyed cat Ommatidium Optic cup embryology Optic cup Optic disc Optic disc drusen ... more details
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- Ultraviolet communication
of numerous ommatidium . Each butterfly ommatidium contains nine photoreceptors ... more details
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- Strabismus (protein)
proteinShort Name vang like 1 van gogh, Drosophila caption image width HGNCid 15512 Symbol VANGL1 AltSymbols EntrezGene 81839 OMIM 610132 RefSeq NM 138959 UniProt Q8TAA9 PDB ECnumber Chromosome Arm Band LocusSupplementaryData Strabismus was originally identified as a Drosophila protein involved in Wnt signaling pathway Planar cell polarity planar cell polarity . ref cite journal author Wolff T, Rubin GM title Strabismus, a novel gene that regulates tissue polarity and cell fate decisions in Drosophila journal Development volume 125 issue 6 pages 1149 59 year 1998 month March pmid 9463361 url http dev.biologists.org cgi pmidlookup?view long&pmid 9463361 ref Flies with mutated stranismus genes have altered development of Ommatidium omatidia in their Compound eye eyes . Vertebrate s have two Strabismus related proteins, VANGL1 and VANGL2 an alternate name for the Drosophila Strabismus protein is Van Gogh . The amino acid sequence and localization studies for Strabismus indicate that it is a membrane protein . Prickle protein Prickle is another protein in the planar cell polarity signaling pathway. Prickle is recruited to the cell biology cell surface Cell membrane membrane by strabismus. ref name Bastock cite journal doi 10.1242 dev.00526 author Bastock R, Strutt H, Strutt D title Strabismus is asymmetrically localised and binds to Prickle and Dishevelled during Drosophila planar polarity patterning journal Development volume 130 issue 13 pages 3007 14 year 2003 month July pmid 12756182 url http dev.biologists.org cgi pmidlookup?view long&pmid 12756182 ref In cells of the developing Drosophila wing, Prickle and Strabismus are concentrated at the cell surface membrane on the most proximal side of cells. ref name Fanto cite journal author Fanto M, McNeill H title Planar polarity from flies to vertebrates journal J. Cell. Sci. volume 117 issue Pt 4 pages 527 33 year 2004 month February pmid 14730010 doi 10.1242 jcs.00973 url http jcs.biologists.org cgi pmidlookup?view lon ... more details
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- Deilephila elpenor
night or scotopic vision . Its eye includes two different kinds of ommatidium each contains nine light ... more details
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- Son of Sevenless
protein Name SOS1 son of sevenless homolog 1 Drosophila caption image width HGNCid 11187 Symbol SOS1 AltSymbols GINGF EntrezGene 6654 OMIM 182530 RefSeq NM 005633 UniProt Q07889 PDB ECnumber Chromosome 2 Arm p Band 21 LocusSupplementaryData protein Name son of sevenless homolog 2 Drosophila caption image width HGNCid 11188 Symbol SOS2 AltSymbols EntrezGene 6655 OMIM 601247 RefSeq NM 006939 UniProt Q07890 PDB ECnumber Chromosome 14 Arm q Band 21 LocusSupplementaryData In cell signalling , Son of Sevenless SOS refers to a set of genes encoding guanine nucleotide exchange factor s that act on the Ras subfamily of small GTPase s. History and name The gene was so named because the Sos protein that it encoded was found to operate downstream of the sevenless gene in Drosophila melanogaster in a MAPK ERK pathway Ras MAP kinase pathway . ref name pmid1846090 cite journal author Rogge RD, Karlovitch CA, Banerjee U title Genetic Dissection of a Neurodevelopmental Pathway Son of sevenless Functions Downstream of the sevenless and EGF Receptor Tyrosine Kinases. journal Cell volume 64 issue 1 pages 39 48 year 1991 month January pmid 1846090 doi 10.1016 0092 8674 91 90207 F url http www.cell.com abstract 0092 8674 2891 2990207 F issn ref When sevenless is mutated or otherwise dysfunctional during development of the fly s ultraviolet light sensitive compound eye , the seventh, central photoreceptor R7 of each ommatidium fails to form. ref name pmid8462097 cite journal author Simon MA, Dodson GS, Rubin GM title An SH3 SH2 SH3 protein is required for p21Ras1 activation and binds to sevenless and Sos proteins in vitro journal Cell volume 73 issue 1 pages 169 77 year 1993 month April pmid 8462097 doi 10.1016 0092 8674 93 90169 Q url issn ref ref name pmid12177507 cite journal author Nimnual A, Bar Sagi D title The two hats of SOS journal Sci. STKE volume 2002 issue 145 pages PE36 year 2002 month August pmid 12177507 doi 10.1126 stke.2002.145.pe36 url issn ref Similarly, the mammalian p ... more details
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- Sri Lankan relict ant
Taxobox name Sri Lankan relict ant image Aneuretus simoni casent0007014 profile 1.jpg status CR status system IUCN2.3 status ref ref name iucn IUCN2008 id 1290 assessors Social Insects Specialist Group year 1996 title Aneuretus simoni downloaded 17 October 2009 ref regnum Animal ia phylum Arthropod a classis Insect a ordo Hymenoptera familia Ant Formicidae subfamilia Aneuretinae genus Aneuretus species A. simoni binomial Aneuretus simoni binomial authority Carlo Emery Emery , 1893 The Sri Lankan relict ant Aneuretus simoni is a species of evolutionarily ancient ant that is placed in a separate tribe biology tribe of its own within the Formicidae family. The genus is monotypic , with the only species Endemism endemic to Sri Lanka where it is known from just a few locations. It is one of the few ant species that are considered endangered. File Aneuretus simoni casent0172259 dorsal 1.jpg thumb left A winged queen The species is the only Extant taxon extant genus in the tribe Aneuretini other members include the extinct Protaneuretus , Paraneretus and Mianeuretus . They are believed to be intermediate in their phylogeny phylogenetic position between the Myrmeciinae Ponerinae and the Dolichoderinae . The workers show very distinct dimorphism with majors being much larger than the minors and lacking few workers intermediate in size. The minor workers are found in the largest numbers within a nest and have a small compound eye having only about 30 ommatidium ommatidia units within the compound eye . The antennae have 12 segments with the segments increasing gradually in size from the base to the tip. The clypeus is broad and flat, lacking any central ridge. The mouthparts show Dolichoderine affinities. ref cite journal title Mouthpart Morphology of the Ant Aneuretus simoni author Gotwald, WH journal Annals of the Entomological Society of America volume 63 issue 4 year 1970 pages 950 952 url http antbase.org ants publications 4899 4899.pdf ref There are outward facing spine ... more details
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- Acropyga
italic title Taxobox name Acropyga image Acropyga.berwicki. .wheeler.svg image caption A. berwicki worker image width 250px regnum Animal ia phylum Arthropod a classis Insect a ordo Hymenoptera familia Formicidae subfamilia Formicinae tribus genus Acropyga genus authority Roger, 1862 type species type species authority diversity link Acropyga diversity 60 species range map range map width 250px subdivision ranks Species subdivision See text. Acropyga is a genus of small Formicinae formicine ant s. Some species can be indirect pests. A. acutiventris , which is found from India to Australia, tends subterranean, root feeding mealybug s of the species Xenococcus Xenococcus annandalei annandalei . Living, gravid females are carried in the jaws of A. acutiventris queens during their nuptial flight, to establish the symbiotic association in founding colonies. Other Acropyga species have relationships with different species of mealybugs, and it could be a trait common to the whole genus. ref name taylor1992 Taylor 1992 ref Description Acropyga are smaller than 3.5 mm, with a compact, stocky body. They have antennae with 10 or 11 segments including the scape , short palps and reduced eyes with four to 30 individual ommatidium ommatidia . In some species the eyes are completely absent. ref name aao Australian Ants Online ref Distribution Acropyga is found in the Americas , southern Africa , India to Southeast Asia and Australia . A. palearctica is known only from Greece . Fossil specimens of Acropyga have been recovered from the Burdigalian stage Dominican amber deposits and several individuals are preserved carrying Electromyrmococcus mealybug s. ref name johnsonetal1995 cite journal last1 Johnson first1 M.S. coauthors et al year 2001 title Acropyga and Azteca Ants Hymenoptera Formicidae with Scale Insects Sternorrhyncha Coccoidea 20 Million Years of Intimate Symbiosis journal American Museum Novitates volume 3335 pages 1 18 doi 10.1206 0003 0082 2001 335 0001 AAAAHF 2.0.CO ... more details
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- Giant isopod
with nearly 4,000 ommatidium facets , wiktionary sessile sessile and spaced far apart on the head ... more details
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- Atlantic horseshoe crab
derived arthropods. ref name Battelle2006 Each ommatidium feeds into a single nerve fiber. Furthermore ... by males when recognizing potential mates. The retinula literally, small retina cells of the ommatidium ... a rhabdom below a crystalline cone, on or near the center of the ommatidium, and always aligned ... more details
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- Trogidae
reason for the dispute between classifications is the possible evolution of the ommatidium in the eyes. The different environments, predators, etc. probably led to the adaptation of ommatidium structures within this family. For example the more advanced and numerous the ommatidium the more present ... more details
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- Arthropod eye
have a generative region at their base, but this elongates with time. Hence the one ommatidium at the apex ... more details
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- Eye
units or ommatidia ommatidium , singular . The image perceived is a combination of inputs ... on the rhabdom , while light from other directions is absorbed by the dark wall of the ommatidium . In the other ... , have specialized zones of ommatidium ommatidia organized into a fovea area which gives acute ... more details
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- Nebula Award for Best Short Story
Sea br by Geoffrey A. Landis The Adinkra Cloth by Mary C. Aldridge The Ommatidium Miniatures by Michael ... more details
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- Thylacocephala
for individual ommatidium . Structural analogy with cirriped peduncle Instead the authors suggest the sac ... more details
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- Sex differences in sensory systems
sensing organelles in the ommatidium ommatidia of eyes 2 to 3 times longer in males than those found ... more details
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- Esperanto vocabulary
a stitch, from sew , lignero a splinter, from wood okulero an ommatidium , from eye , vortero a morpheme ..., sometimes beyond what they know in their native language. For instance, the English word ommatidium ... more details
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- Mantis shrimp
compound eye is made up of up to 10,000 separate ommatidium ommatidia of the Eye Apposition eyes apposition ... more details
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- Drosophila melanogaster
eyes or ommatidia , and are one of the most advanced among insects. Each ommatidium contains 8 photoreceptor ... more details
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- Michael Bishop (author)
World Fantasy Award nominee The Ommatidium Miniatures 1989 Nebula Award nominee Life Regarded as a Jigsaw ... more details
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- Insect morphology
eye s composed of units called ommatidia ommatidium , singular , of which there may be up to 30,000 ... more details
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- List of Greek and Latin roots in English
wikt omentum omentum omin Latin wikt omen Latin omen , ominis ominous omm eye Greek omma ommatidium ... more details
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- Arthropod
geometry cross section . Each ommatidium is an independent sensor, with its own light sensitive cells ... more details
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