ANIMAL REPRODUCTION AND DEVELOPMENT
SEXUAL REPRODUCTION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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2
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4
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10
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16
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Detailed explanation-1: -This division is an important event since after fertilisation haploid chromosomes from each gamete (male and female) fuse to retain the diploid state in the zygote. Diploid means two sets of chromosome and haploid is one set. Since here the diploid set is 16 thus one set will be half it, i.e, 8.
Detailed explanation-2: -16 cells will be produced if a cell divides mitotically four times. Q. How many times a cell will have to divide mitotically, to form 128 cells?
Detailed explanation-3: -For the first 12 hours after conception, the fertilized egg remains a single cell. After 30 hours or so, it divides from one cell into two. Some 15 hours later, the two cells divide to become four. And at the end of 3 days, the fertilized egg cell has become a berry-like structure made up of 16 cells.
Detailed explanation-4: -So, if the parent cell has 16 chromosomes, after meiotic division it will get reduced to half and thus, the daughter cells will have 8 chromosomes.