Barack Obama
From Wikipedia, the free encyclopedia
Barack Hussein Obama II (US 
i/bəˈrɑːk huːˈseɪn ɵˈbɑːmə/, born August 4, 1961) is the 44th and current President of the United States, and the first African American to hold the office.
2. He is now president since 6 years, 3 months and 26 days. Born in Honolulu, Hawaii.
3. Obama is a graduate of Columbia University and Harvard Law School, where he served as president of the Harvard Law Review.
4. He was a community organizer in Chicago before earning his law degree. He worked as a civil rights attorney and taught constitutional law at the University of Chicago Law School from 1992 to 2004. He served three terms representing the 13th District in the Illinois Senate from 1997 to 2004, running unsuccessfully for the United States House of Representatives in 2000.
i/bəˈrɑːk huːˈseɪn ɵˈbɑːmə/, born August 4, 1961) is the 44th and current President of the United States, and the first African American to hold the office.2. He is now president since 6 years, 3 months and 26 days. Born in Honolulu, Hawaii.
3. Obama is a graduate of Columbia University and Harvard Law School, where he served as president of the Harvard Law Review.
4. He was a community organizer in Chicago before earning his law degree. He worked as a civil rights attorney and taught constitutional law at the University of Chicago Law School from 1992 to 2004. He served three terms representing the 13th District in the Illinois Senate from 1997 to 2004, running unsuccessfully for the United States House of Representatives in 2000.
5. In 2004, Obama received national attention during his campaign to represent Illinois in the United States Senate with his victory in the March Democratic Party primary, his keynote address at the Democratic National Convention in July, and his election to the Senate in November.
6. He began his presidential campaign in 2007 and, after a close primary campaign against Hillary Rodham Clinton in 2008, he won sufficient delegates in the Democratic Party primaries to receive the presidential nomination. He then defeated Republican nominee John McCain in the general election, and was inaugurated as president on January 20, 2009. Nine months after his election, Obama was named the 2009 Nobel Peace Prize laureate.
7. During his first two years in office, Obama signed into law economic stimulus legislation in response to the Great Recession in the form of the American Recovery and Reinvestment Act of 2009 and the Tax Relief, Unemployment Insurance Reauthorization, and Job Creation Act of 2010. Other major domestic initiatives in his first term included thePatient Protection and Affordable Care Act, often referred to as "Obamacare"; the Dodd–Frank Wall Street Reform and Consumer Protection Act; and the Don't Ask, Don't Tell Repeal Act of 2010.
8. In foreign policy, Obama ended U.S. military involvement in the Iraq War, increased U.S. troop levels in Afghanistan, signed the New START arms control treaty with Russia, ordered U.S. military involvement in Libya in opposition to Muammar Gaddafi, and ordered the military operation that resulted in the death of Osama bin Laden.
9.In January 2011, the Republicans regained control of the House of Representatives as the Democratic Party lost a total of 63 seats; and, after a lengthy debate over federal spending and whether or not to raise the nation's debt limit, Obama signed the Budget Control Act of 2011 and theAmerican Taxpayer Relief Act of 2012.
10. Obama was reelected president in November 2012, defeating Republican nominee Mitt Romney, and was sworn in for a second term on January 20, 2013.
11. During his second term, Obama has promoted domestic policies related to gun control in response to the Sandy Hook Elementary School shooting, and has called for full equality for LGBTAmericans, while his administration has filed briefs which urged the Supreme Court to strike down the Defense of Marriage Act of 1996 and California's Proposition 8 as unconstitutional. In foreign policy, Obama ordered U.S. military involvement in Iraq in response to gains made by the Islamic State in Iraq after the 2011 withdrawal from Iraq, continued the process of ending U.S. combat operations in Afghanistan, and has sought to normalize U.S. relations with Cuba.
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11. During his second term, Obama has promoted domestic policies related to gun control in response to the Sandy Hook Elementary School shooting, and has called for full equality for LGBTAmericans, while his administration has filed briefs which urged the Supreme Court to strike down the Defense of Marriage Act of 1996 and California's Proposition 8 as unconstitutional. In foreign policy, Obama ordered U.S. military involvement in Iraq in response to gains made by the Islamic State in Iraq after the 2011 withdrawal from Iraq, continued the process of ending U.S. combat operations in Afghanistan, and has sought to normalize U.S. relations with Cuba.
Also See The Following if You Wish:-
Common wheat
From Wikipedia, the free encyclopedia
| Common wheat | |
|---|---|
 | |
| Ears of common wheat | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Monocots |
| (unranked): | Commelinids |
| Order: | Poales |
| Family: | Poaceae |
| Subfamily: | Pooideae |
| Tribe: | Triticeae |
| Genus: | Triticum |
| Species: | T. aestivum |
| Binomial name | |
| Triticum aestivum L. | |
| Synonyms | |
Common wheat (Triticum aestivum), also known as bread wheat, is a cultivated wheatspecies.[1][2][3][4][5] About 95% of the wheat produced is common wheat.[6]
Contents
Nomenclature and taxonomy of wheat and its cultivars[edit]
Further information: Taxonomy of wheat
Numerous forms of wheat have evolved under human selection. This diversity has led to confusion in the naming of wheats, with names based on both genetic and morphological characteristics. For more information, see the taxonomy of wheat.
List of the common cultivars[edit]
Evolution[edit]
Bread wheat is an allohexaploid (anallopolyploid with six sets of chromosomes, two sets from each of three different species). Free-threshing wheat is closely related to spelt. As with spelt, genes contributed from goatgrass (Aegilops tauschii) give bread wheat greater cold hardiness than most wheats, and it is cultivated throughout the world's temperate regions.
Of the six sets of chromosomes, two come fromTriticum urartu (einkorn wheat) and two fromAegilops speltoides. This hybridisation created the species Triticum turgidum, 580-820 thousand years ago. The last two sets of chromosomes came from Aegilops tauschii, 230-430 thousand years ago.[6][8]
History[edit]
Common wheat was first domesticated inWestern Asia during the early Holocene, and spread from there to North Africa, Europe and East Asia in the prehistoric period.
Wheat first reached North America with Spanish missions in the 16th century, but North America's role as a major exporter of grain dates from the colonization of the prairies in the 1870s. As grain exports from Russia ceased in the First World War, grain production in Kansasdoubled.
Worldwide, bread wheat has proved well adapted to modern industrial baking, and has displaced many of the other wheat, barley, and rye species that were once commonly used for breadmaking, particularly in Europe.
Plant breeding[edit]
Modern wheat varieties have short stems, the result of RHt dwarfing genes [9] that reduce the plant's sensitivity togibberellic acid, a plant hormone that lengthens cells. RHt genes were introduced to modern wheat varieties in the 1960s byNorman Borlaug from Norin 10 cultivars of wheat grown in Japan. Short stems are important because the application of high levels of chemical fertilizers would otherwise cause the stems to grow too high, resulting in lodging (collapse of the stems). Stem heights are also even, which is important for modern harvesting techniques.
Other forms of common wheat[edit]
Compact wheats (e.g., club wheatTriticum compactum, but in India T. sphaerococcum) are closely related to common wheat, but have a much more compact ear. Their shorter rachis segments lead to spikelets packed closer together. Compact wheats are often regarded as subspecies rather than species in their own right (thus T. aestivum subsp. compactum).
References[edit]
- ^ Brenchley, R; Spannagl, M; Pfeifer, M; Barker, G. L.; d'Amore, R; Allen, A. M.; McKenzie, N; Kramer, M; Kerhornou, A; Bolser, D; Kay, S; Waite, D; Trick, M; Bancroft, I; Gu, Y; Huo, N; Luo, M. C.; Sehgal, S; Gill, B; Kianian, S; Anderson, O; Kersey, P; Dvorak, J; McCombie, W. R.; Hall, A; Mayer, K. F.; Edwards, K. J.; Bevan, M. W.; Hall, N (2012). "Analysis of the bread wheat genome using whole-genome shotgun sequencing". Nature 491 (7426): 705–10. doi:10.1038/nature11650. PMC 3510651.PMID 23192148.
- ^ Bonjean, Alain P. and William J. Angus (eds) (2001). The world wheat book : a history of wheat breeding. Andover: Intercept. p. 1131. ISBN 1-898298-72-6. Excellent resource for 20th century plant breeding.
- ^ Caligari, P.D.S. and P.E. Brandham (eds) (2001).Wheat taxonomy : the legacy of John Percival. London: Linnean Society, Linnean Special Issue 3. p. 190.
- ^ Heyne, E.G. (ed.) (1987). Wheat and wheat improvement. Madison, Wis.: American Society of Agronomy. p. 765. ISBN 0-89118-091-5.
- ^ Zohary, Daniel and Maria Hopf (2000).Domestication of Old World plants: the origin and spread of cultivated plants in West Asia. Oxford: Oxford University Press. p. 316. ISBN 0-19-850356-3. Standard reference for evolution and early history.
- ^ a b Mayer, K. F. X. (2014). "A chromosome-based draft sequence of the hexaploid bread wheat (Triticum aestivum) genome". Science 345 (6194): 1251788. doi:10.1126/science.1251788.
- ^ a b Sanità Di Toppi, L.; Castagna, A.; Andreozzi, E.; Careri, M.; Predieri, G.; Vurro, E.; Ranieri, A. (2009). "Occurrence of different inter-varietal and inter-organ defence strategies towards supra-optimal zinc concentrations in two cultivars of Triticum aestivum L". Environmental and Experimental Botany 66 (2): 220.doi:10.1016/j.envexpbot.2009.02.008.
- ^ Marcussen, T. (2014). "Ancient hybridizations among the ancestral genomes of bread wheat".Science 345 (6194): 1250092.doi:10.1126/science.1250092.
- ^ m., E.; w., S.; k., G.; g., R.; r., R. (2002). ""Perfect" markers for the Rht-B1b and Rht-D1b dwarfing genes in wheat". TAG Theoretical and Applied Genetics 105 (6–7): 1038. doi:10.1007/s00122-002-1048-4.
See also[edit]
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