Child Psychology

Down syndrome , also commonly know as Trisomy 21 , is a contractable condition resulting in the presence on part or all of an superfluous 21st chromosome This is characterized by a grouping of both major and minor anomalies of embody structure and function (Roizen Patterson , 2003 . Impairment of learning and physical produce , as well as facial appearance is extradite in the majority of cases (Roizen Patterson , 2003Most cases of Down syndrome be not catching , but occur as random events during the formation of the fruitful electric cellular phones , both eggs and sperm . An error in cell division call nondisjunction results in reproductive cells with abnormal follow of chromosomes (National Library of medicament , 2006 . For instance , either an egg or sperm cell may contain an extra retroflex of chromosome 21 . If this cell contributes to the singular s hereditary makeup , the individual will have an extra copy of chromosome 21 in every cell in their body (National Library of medicate 2006 . An un change person shadow pay a rearrangement of transmittable material between chromosome 21 and other chromosomes . This is called a match translocation . Even though , this individual shows no signs of Down syndrome , individuals who carry this type of balanced translocation are at a greater risk of having a Down syndrome child (National Library of Medicine , 2006Individuals who carry Down Syndrome will have all or some of the following physical characteristics : muscle hypontia , oblique warmheartedness fissures that has a small skin fold on the informal corner , flat nasal passage , enlargement and sound projection of the tongue , relatively short neck , white floating policy within the iris , excessive flexibility within the joints , indwelling heart defects , and single flexion furrow of the fifth leaf (Wood , 2003 . Individuals with Down syndrome also have mental retardation in the mild to moderate IQrange (50-70 35-50 .

However , individuals with mosaic Down Syndrome give the gate have IQ scores up to 30 points high (Wood , 2003The chromosomal abnormality is characterized by the presences of an extra copy of genetic material on the 21st chromosome . The effect due to the extra chromosome differs from individual to individual and by numerous factors , including genetic and environmental factors (Mitelman 1995Mosaic Down syndrome can occur when a nondisjuction during an early cell division in a normal embryo , which leads to carve up of the cells with Trisomy 21 . Mosaic Down Syndrome can also go along when the Down syndrome embryo undertakes nondisjunction and cells in embryo revert stern to the normal chromosomal arrangement (Leshin , 2000 . There is evidence that Mosaic Down Syndrome can produce a lesser developmental delay than Trisomy 21 (Leshin , 2000Mosaic Down Syndrome is discovered finished genetic testing where 20-25 cells are examined . Due to the cells in Trisomy 21 are all infected , if only some are affected than the diagnosis of mosaicism is determined (Leshin , 2000 . If suspected and not confirmed through blood testing , a skin and bone snapper test are commonly the next line in detection (Leshin , 2000A chromosomal mutation - centric fusion - can cause Down syndrome known as Robertsonian translocation . In...If you want to limit a full essay, order it on our website: Ordercustompaper.com

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