SSC
BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A failure of chromosomes to separate at anaphase.
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A hip new pop band.
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When chromosomes pair up at the equator.
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When chromosomes separate at anaphase
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Detailed explanation-1: -During anaphase of the cell cycle, chromosomes are separated to opposite ends of the cell to create two daughter cells. Nondisjunction is the failure of the chromosomes to separate, which produces daughter cells with abnormal numbers of chromosomes. [
Detailed explanation-2: -Nondisjunction is the miss segregation of a homologous pair of chromosomes during meiosis (figure 1). It leads to the formation of a new cell with an abnormal amount of genetic material.
Detailed explanation-3: -During the anaphase stage of mitosis, these chromatids separate, and one chromatid goes into each daughter cell. However, when nondisjunction occurs, the chromatids do not separate. The result is that one cell receives both chromatids, while the other cell receives neither.
Detailed explanation-4: -The failure of chromosomes to separate may occur via: Failure of homologues to separate in Anaphase I (resulting in four affected daughter cells) Failure of sister chromatids to separate in Anaphase II (resulting in only two daughter cells being affected)