CELL STRUCTURES AND FUNCTION
CELL DIVISION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -Normally, people are born with 23 chromosome pairs, or 46 chromosomes, in each cell-one inherited from the mother and one from the father. A numerical chromosome abnormality can cause each cell to have 45 or 47 chromosomes in each cell.
Detailed explanation-2: -Humans have 23 pairs of chromosomes. A trisomy is a chromosomal condition characterised by an additional chromosome. A person with a trisomy has 47 chromosomes instead of 46. Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy.
Detailed explanation-3: -About half of all girls with Turner syndrome have a monosomy disorder. Monosomy means that a person is missing one chromosome in the pair. Instead of 46 chromosomes, the person has only 45 chromosomes.
Detailed explanation-4: -Eighty percent of 45, X karyotypes can be attributed to paternal nondisjunction, although some of these cases may be caused by early loss of the Y chromosome through mitotic nondisjunction in the zygote.