In general, sex chromosome aneuploidies are less lethal than autosomal aneuploidies since: sex chromosomes contain information for sex determination only, they are not necessary for the survival of the organism our species is able to have organisms survive with only one of the sex chromosomes functioning (it must be an X) sex chromosomes are the smallest chromosomes sex chromosomes are only present in cells in gonadal tissue and do not have a large effect on the organism
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Sex chromosomes contain information for sex determination only: This statement is not entirely true. While sex chromosomes do play a major role in sex determination, they also contain genes that are important for other functions in the body. Show more…
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Normally, having three copies of a chromosome results in severe developmental problems and death. Females with the genotype XXX have three copies of the sex chromosomes and are infertile, but are otherwise nearly "normal". Which of the following explains this? A. The "extra" X chromosome is lost from the cells. B. The "extra" X chromosome is converted into a chromosome. C. Every chromosome but one is inactivated. D. X chromosomes do not carry any important genes. QUESTION 5 What causes "nondisjunction"? A. One pair of sister chromatids fails to separate during meiotic formation. B. Both possibilities are correct. C. Neither possibility is correct.
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