LABORATORY REVIEW
MITOSIS AND MEIOSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Even cells pass on to the gamete
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Uneven cells pass on to the gamete
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Even cells pass on to the zygote
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Uneven cells pass on to the zygote
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Detailed explanation-1: -Chromosome abnormalities often happen due to one or more of these: Errors during dividing of sex cells (meiosis) Errors during dividing of other cells (mitosis) Exposure to substances that cause birth defects (teratogens)
Detailed explanation-2: -An error in cell division called nondisjunction results in reproductive cells with an abnormal number of chromosomes. For example, a reproductive cell may accidentally gain or lose one copy of a chromosome.
Detailed explanation-3: -Most chromosome abnormalities occur as an accident in the egg or sperm. In these cases, the abnormality is present in every cell of the body. Some abnormalities, however, happen after conception; then some cells have the abnormality and some do not.
Detailed explanation-4: -Some genetic disorders are caused by chromosomal abnormalities due to errors in meiosis, the process which produces reproductive cells such as sperm and eggs. Examples include Down syndrome (extra chromosome 21), Turner Syndrome (45X0) and Klinefelter’s syndrome (a male with 2 X chromosomes).