Wikify date December 2009 Dichogamy , also known as sequential hermaphrodite hermaphrodism , is the separation in time of gender expression in a hermaphroditic organism, a characteristic of some fishes , gastropods , crustaceans and most flowering plants . This is the opposite of simultaneous hermaphrodites, or homogamy . In fish Many species of coral reef fish , such as Blunt headed wrasse s, are dichogamous. All are born female but, but if a territory holding male dies, then the largest female will become male. In flowering plants In the context of the plant sexuality of flowering plants angiosperms , there are two forms of dichogamy protogyny &mdash female function precedes male function&mdash and protandry &mdash male function precedes female function. Historically, dichogamy has been regarded as a mechanism for reducing inbreeding e.g., Darwin, 1862 . However, a survey of the angiosperms found that self incompatibility in plants self incompatible SI plants, which are incapable of inbreeding, were as likely to be dichogamous as were self compatible SC plants Bertin, 1993 . This finding led to a reinterpretation of dichogamy as a more general mechanism for reducing the impact of pollen Carpel pistil interference on pollen import and export reviewed in Lloyd & Webb, 1986 Barrett, 2002 . Unlike the inbreeding avoidance hypothesis, which focused on female function, this interference avoidance hypothesis considers both gender functions. In many hermaphroditic species, the close ... force in floral biology Harder & Barrett, 1995, 1996 Harder & Wilson, 1998 Barrett, 2002 . Dichogamy ... visitation and siring success. Harder et al. 2000 demonstrated experimentally that dichogamy ... 65 year 1985 cite journal doi 10.2307 2445372 author Bertin, R.I. title Incidence of monoecy and dichogamy ... 3B2 V cite journal doi 10.1007 BF02856676 author Bertin R.I., Newman C.M. title Dichogamy in angiosperms ... between the presentation of pollen and stigmas in angiosperms I. Dichogamy journal New Zeal. J. Bot ... more details
Unreferenced date May 2009 Herkogamy is a common strategy employed by hermaphroditic angiosperms to reduce sexual interference between male anthers and female stigma function. Herkogamy differs from other such strategies e.g. dichogamy by supplying a spatial separation of the anthers and stigma. Two forms of herkogamy are most common 1. Approach Herkogamy is the presentation of the stigma above the level of the anthers. This arrangement of sex organs causes floral visitors to first contact the stigma, before removing pollen from the anthers. This form of herkogamy is considered to be common, and is associated with a large, diverse fauna of floral visitors pollinators. 2. Reverse Herkogamy is displayed when the stigma is recessed below the level of the anthers. This arrangement causes floral visitors to first contact the anthers before the stigma. For this reason, reverse herkogamy is believed to facilitate greater pollen export than approach herkogamy. This type of sex organ arrangement is typically associated with Lepidopteran moths and butterflies pollination. Category Pollination Category Plant morphology de Herkogamie fr Herkogamie no Herkogami sr ... more details
wiktionary In sociology Homogamy is marriage between individuals who are, in some culturally important way, similar to each other. Homogamy may be based on socio economic status, class, gender, ethnicity, or religion. ref http bitbucket.icaap.org dict.pl?term HOMOGAMY Homogamy . Online Dictionary of the Social Sciences . ref It is a form of assortative mating . It can also refer to the socialization customs of a particular group such that people who are similar in religion, class, gender, or culture tend to socialize with one another. Homogamy has been suggested as a term for same sex marriage or other union, and heterogamy as a term for marriage or union between people of different sexes. ref http www.unc.edu pnc JFTR2011.pdf Homogamy Unmodified, by Philip N. Cohen. Journal of Family Theory and Review 3 47 51 2011 . ref ref http www.connellodonovan.com abom.html The Abominable and Detestable Crime Against Nature A Revised History of Homosexuality & Mormonism, 1840 1980 2004 by Connell O Donovan. ref In biology Homogamy is used in biology in two separate senses, both involving actual or potential matings. Inbreeding can be referred to as homogamy. ref Walker, P.M.B. ed. 1988. The Wordsworth Dictionary of Science and Technology . W. R. Chambers Ltd. and Cambridge University Press. ref More often, homogamy refers to the maturation of male and female reproductive organs at the same time, which is also known as simultaneous or synchronous hermaphrodite hermaphrodism and is the antonym of dichogamy . See also Endogamy References references External links http www.just25words.co.uk images cq compatibility quotient.pdf Partner similarity and relationship satisfaction development of a compatibility quotient . Glenn Wilson psychologist Glenn D. Wilson & Jon M. Cousins. Sexual and Relationship Therapy , Vol 18, No. 2, 2003. Category Marriage socio stub biol stub de Homogamie es Homogamia fr Homogamie he nl Homogamie no Homogami pl Homogamia sv Homogami ... more details
File Andrei Bolotov.jpg thumb Andrey Bolotov Andrey Timofeyevich Bolotov 18 October 1738 16 October 1833 was the most distinguished Russia n agriculturist of the 18th century. Bolotov was born and spent most of his adult life in the family estate of Dvoryaninovo, in the Tula, Russia Tula guberniya region to the south of Moscow . He was brought up by his parents in Livland , where his father s regiment was stationed. After taking part in the Seven Years War he settled into retirement in Dvoryaninovo. During his life there, he brought out a pioneering manual on crop rotation and elaborated an innovative system of pomology which included more than 600 cultivar s of apple and pear. Always interested in plant breeding , Bolotov discovered dichogamy of apple trees and pointed out to the advantages of cross pollination . Bolotov s works brought him to the attention of Count Orlov , who asked him to manage the neighbouring estate of Bobriki , where Catherine II of Russia Catherine II s illegitimate son, Count Bobrinsky , was being raised. Bolotov turned Bobriki into the most up to date agricultural estate in provincial Russia and ensured the keen interest which later Counts Bobrinsky would take in agriculture. Bolotov was also active in the Free Economic Society , which published his treatise on forestry . Together with Nikolay Novikov , he edited the journals The Village Resident 1778 79 and The Magazine of Economics 1780 89 , which brought him the income of 400 roubles a year, a very considerable sum for the time. His extensive memoirs, entitled Life and Adventures of Andrei Bolotov, in 26 parts and written between 1789 and 1816, went through several editions and were translated into English. Bolotov died in Dvoryaninovo aged 96. References . . . . . ., 1949 Andrei R zikov Persondata Metadata see Wikipedia Persondata . NAME Bolotov, Andrey ALTERNATIVE NAMES SHORT DESCRIPTION DATE OF BIRTH 18 October 1738 PLACE OF BIRTH DA ... more details
taxobox name Tricyrtis image Tricyrtis hirta blossom top aka .jpg image caption Tricyrtis hirta regnum Plantae unranked divisio Angiosperms unranked classis Monocots ordo Liliales familia Liliaceae subfamilia Calochortoideae genus Tricyrtis genus authority Nathaniel Wallich Wall. subdivision ranks Species subdivision See text. Tricyrtis is a genus biology genus of the botany botanical family biology family Liliaceae , known in English as Toad lilies. Its native range is from the Himalayas to eastern Asia, including China, ref name china cite web work Flora of China url http efloras.org florataxon.aspx?flora id 2&taxon id 133597 title Tricyrtis Wallich ref Japan, ref Cite journal url http www.amjbot.org cgi content full 86 2 287 doi 10.2307 2656945 title The Effect of Geographic Range and Dichogamy on Genetic Variability and Population Genetic Structure in Tricyrtis Section Flavae Liliaceae year 1999 author Maki, Masayuki journal American Journal of Botany volume 86 pages 287 jstor 2656945 author2 Morita, Hiroko author3 Oiki, Syuji author4 Takahashi, Hiroshi issue 2 publisher Botanical Society of America postscript None ref Philippines and Formosa . ref name George2002 Cite book last George Schmid first W. year 2002 title An encyclopedia of shade perennials pages 312 url http books.google.com ?id oKVsZdgB QEC&pg RA1 PA312&dq Tricyrtis are native from isbn 0881925497 publisher Timber Press location Portland, Or. postscript None ref They are perennial herbaceous plant s that grow naturally at the edge of forests. They prefer shade or part shade and rich, moist soil. Toad Lilies bloom in the fall. They are hardy enough to handle sudden changes of winter from mild to blustery cold. ref Cox, Jeff 1998 by Rodale Press Perennial All Stars The 150 Best Perennials for Great Looking, Trouble Free Gardens, pg. 305 ref Species Species include Tricyrtis affinis small Tomitaro Makino Makino small Tricyrtis amethystina small Genkei Masamune Masam. small Tricyrtis chinensis small Hi ... more details
Environmental sex determination or ESD is any sex determination system in which sex is established by a nongenetic cue e.g. nutrient availability experienced within a discrete period after conception. In contrast, genotypic sex determination GSD occurs when sex is established by genetic factors e.g. sex chromosome s at conception. ref name janzen cite journal author F. J. Janzen & P. C. Phillips year 2006 title Exploring the evolution of environmental sex determination, especially in reptiles journal Journal of Evolutionary Biology volume 19 issue 6 pages 1775 1784 doi 10.1111 j.1420 9101.2006.01138.x pmid 17040374 url http www.public.iastate.edu fjanzen pdf 06JEB.pdf format Portable Document Format PDF ref Environmental sex determination should also not be confused with some forms of hermaphroditism in which the sex is determined flexibly after birth, such as dichogamy . Examples In the season in the amphipod Gammarus duebeni , photoperiod induces production of males earlier, and females later. Because male fitness improves more than female fitness with increased size, environmental sex determination is adaptive in this system by permitting males to experience a longer growing season than females. ref cite journal author J. McCabe & A. M. Dunn year 1997 title Adaptive significance of environmental sex determination in an amphipod journal Journal of Evolutionary Biology volume 10 issue 4 pages 515 527 doi 10.1046 j.1420 9101.1997.10040515.x ref The adaptive significance of environmental sex determination is not so clear for amniote s, however, the clade in which this it is perhaps most common. Most amniote vertebrates have genetic sex determination, but a small highly diverse set of taxa in this clade show environmental sex determination. In these latter animals, environmental sex determination occurs as temperature dependent sex determination TSD , wherein sex of individuals is permanently determined by thermal conditions experienced approximately during the middle ... more details
italictitle Taxobox name Calyptraea chinensis image Cuncha GFDL Galicia2.jpg image caption Calyptraea chinensis regnum Animal ia phylum Mollusca classis Gastropoda unranked familia clade Caenogastropoda br clade Hypsogastropoda br clade Littorinimorpha superfamilia Calyptraeoidea familia Calyptraeidae subfamilia genus Calyptraea subgenus species C. chinensis binomial Calyptraea chinensis binomial authority Linnaeus, 1758 synonyms ref ref name WoRMS synonyms Calyptraea sinensis small Linnaeus, 1758 small Calyptraea chinensis , common name the Chinese hat snail or Chinese hat shell, is a species of small sea snail , a marine gastropod mollusk in the family biology family Calyptraeidae , the slipper snails or slipper limpets, cup and saucer snails, and Chinese hat snails. ref name WoRMS WRMS species 138961 Calyptraea chinensis Linnaeus, 1758 Gofas, S. 2009 . Calyptraea chinensis Linnaeus, 1758 . In Bouchet, P. Gofas, S. Rosenberg, G. 2009 World Marine Mollusca database. Accessed through the World Register of Marine Species at nowiki http www.marinespecies.org aphia.php?p taxdetails&i nowiki on 2010 06 03 ref ref Collins pocket guide, Sea Shore of Britain and Europe , HarperCollinsPublishers, London, 1996, ISBN 0 00 219955 6 ref Description The thin Gastropod shell shell of this species has the shape of an almost symmetrical cone like a Chinese hat or conical Asian hat , 7 mm high and 15 21 mm wide. The internal partition has a spirally curved edge which runs running from the Apex mollusc apex to the margin of the shell, and partly covers the Aperture mollusc aperture . The presence of this internal shelf distinguishes this species easily from the true limpet s. The aperture is round and adapted to the substrate. The shell is creamy white, and glossy on the inside. Calyptraea chinensis is a filter feeder , binding fine food particles with mucus . Like all slipper limpets, this species is a Dichogamy protandrous hermaphrodite , but the stages of change from mal ... more details
Image Aleksandr Oparin and Andrei Kursanov in enzymology laboratory 1938.jpg thumb right 210px Biologists Aleksandr Oparin right and Andrei Kursanov left in the enzymology laboratory, 1938 This list of Russia n biologist s includes the famous biologists from the Russian Federation , the Soviet Union , the Russian Empire and other predecessor states of Russia. Biologists of all specialities may be listed here, including naturalist s, botanist s, zoologist s, paleontologist s, biochemist s, physiologist s and others. Expand list date February 2011 Alphabetical list compactTOC8 side yes seealso yes NOTOC A Johann Friedrich Adam , discoverer of the Adams mammoth , the first complete woolly mammoth skeleton Igor Akimushkin , notable biologist Vladimir Prokhorovich Amalitskii , notable paleontologist Nicolai Ivanovich Andrusov Nicolai Andrusov , notable palaeontologist Andrey Avinoff , notable entomologist B Karl Baer , naturalist, founder of the Russian Entomological Society , formulated embryological Baer s laws Alexander Barchenko , notable for his research of Hyperborea Jacques von Bedriaga , prominent herpetologist , described Bedriaga s Rock Lizard and Bedriaga s Skink Andrey Belozersky , founder of molecular biology Dmitry Konstantinovich Belyaev Dmitry Belyaev , domesticated silver fox Lev Berg , ichthyologist of Central Asia and European Russia Yuli Berkovich , experimented with seed germination in zero gravity Nikolai Bernstein , neurophysiologist, coined the term biomechanics Vladimir Betz , discovered giant pyramidal neurons of primary motor cortex Anatoli Petrovich Bogdanov , notable biologist Andrey Bolotov , major 18th century agriculturist , discovered dichogamy , pioneered cross pollination August von Bongard , botanist of Alaska , discoverer of Sitka Spruce and Red Alder Antonina Borissova , notable botanist Zinaida Botschantzeva , notable botanist Alexander Bunge , major botanist of Siberia especially Altai File Andrei Bolotov.jpg thumb 90px Andrei Bolo ... more details
dichogamyDichogamy, also known as sequential hermaphrodism, is the separation in time of gender ... points in their life cycle dichogamy . Homogamy is the maturation in hermaphroditic animals ... in which an organism changes sex during its lifetime. ref http www.wordnik.com words dichogamyDichogamy ... more details
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