Polyploidy - Turner syndrome individuals that are treated...

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Polyploidy Polyploidy is a condition in which there is more than 2 sets of chromosomes. Triploids (3N), tetraploids (4N), pentaploids (5N) etc. are polyploids. Polyploidy in Plants Polyploidy is a major evolutionary mechanism in plants. Approximately 47% of all flowering plants are polyploid. Some examples of polyploid plant species are corn, wheat, cotton, sugarcane, apples, bananas, watermelons, and many flowers. Polyploid plants are often more vigorous than the diploid parent species. Polyploid plants are fertile. Polyploidy in Humans Polyploids have defects in nearly all organs. Most die as embryos or fetuses. Occasionally an infant survives for a few days. Abnormalities of the Sex Chromosomes Turner Syndrome - XO Characteristics of Turner syndrome include the following: Sexually underdeveloped Short stature Folds of skin on the back of the neck Wide-spaced nipples Narrow aorta Pigmented moles 97% die before birth Malformed elbows Infertile Normal Intelligence The incidence of Turner syndrome is 1 in 2000 female births.
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Unformatted text preview: Turner syndrome individuals that are treated with hormones lead fairly normal lives. XXX - Triple-X Syndrome (also XXXX and XXXXX) Triple-X individuals are tall and thin and have menstrual irregularities. Their IQ is in the normal range but it is slightly reduced. The incidence of Triple-X Syndrome is 1 in 1,500 female births. Additional X chromosomes are associated with an increased mental handicap. XXY - Klinefelter Syndrome (also XXXY) Males with two or more X chromosomes have Klinefelter Syndrome. The incidence of Klinefelter Syndrome is 1 in 1000 male births. Symptoms include reduced sexual maturity and secondary sexual characteristics, breast swelling (gynecomastia), and infertility. Klinefelter males are slow to learn and individuals with additional X’s (XXXY) may be mentally retarded. XYY - Jacob Syndrome Most XYY males are normal and are unaware of an additional chromosome. XYY males tend to be tall and may have speech and reading problems....
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This note was uploaded on 01/04/2012 for the course BSC BSC1005 taught by Professor Orlando,rebecca during the Fall '10 term at Broward College.

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Polyploidy - Turner syndrome individuals that are treated...

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