Aphenotypically normal couple has a colorblind klinefelter son (xxy). in which parent and at what meiotic stage must the non-disjunction event have occurred? a. meiosis i of mother b. meiosis i of father c. meiosis ii of father d. meiosis ii of mother e. meiosis i or ii of mother f. meiosis i or ii of father

Answer;

D. Meiosis ii of mother

Explanation;

-The non-disjunction occurs in the meiosis II of the mother. This non-disjunction occurs when the two sister chromatids X and X fails to separate during meiosis II and produces an egg having two X chromosomes.

-Klinefelter syndrome is a condition that occurs in males when they have an extra X chromosome. The syndrome is not inherited, but usually occurs as a random event during the formation of reproductive cells (eggs and sperm) that results in the presence of one extra copy of the X chromosome in each cell (47,XXY).

which

what is a measurement of the earth’s history divided into time periods?

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sedimentary rock

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radioactive elements