HEREDITY
NONDISJUNCTION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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23
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22
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44
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46
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Detailed explanation-1: -In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46.
Detailed explanation-2: -Human somatic cells have 46 chromosomes consisting of two sets of 22 homologous chromosomes and a pair of nonhomologous sex chromosomes. This is the 2n, or diploid, state. Human gametes have 23 chromosomes or one complete set of chromosomes. This is the n, or haploid, state.
Detailed explanation-3: -There are 23 pairs of chromosomes in somatic cells; one member of each pair is paternal (from the father) and one maternal (from the mother). There are 22 matched pairs of autosomal chromosomes, plus one pair of sex chromosomes.
Detailed explanation-4: -Humans, like many other species, are called ‘diploid’. This is because our chromosomes exist in matching pairs – with one chromosome of each pair being inherited from each biological parent. Every cell in the human body contains 23 pairs of such chromosomes; our diploid number is therefore 46, our ‘haploid’ number 23.
Detailed explanation-5: -In plants and animals (including humans), chromosomes reside in the nucleus of cells. Humans have 22 pairs of numbered chromosomes (autosomes) and one pair of sex chromosomes (XX or XY), for a total of 46.