Q. 12
In our society a woman is often blamed for not bearing male child. Do you think it is right? Justify.
Answer :
I don’t think it is right to blame women for not bearing male child.
As the sex determining mechanism in case of humans is of XY type. Of the 23 pairs of chromosomes, 22 pairs are autosomes and are same in both male and females. The remaining one pair is different that is a pair of X chromosomes in females and an X and Y chromosome in males. During spermatogenesis half of the sperms produced by males carry X chromosomes and the other half of sperms carry Y chromosomes besides autosomes. However females produce ovum with X chromosome. There are equal chances of fertilisation of ovum with sperm carrying X or Y chromosome. An ovum fusing with a sperm carrying X chromosome results in zygote developing into a female(XX) and an ovum fusing with a sperm carrying Y chromosome results in a zygote developing into male (XY)offspring.
Thus it is clear that genetic makeup of sperm determines the sex of the child. Also for each pregnancy there is always 50% probability of either a male or female child.
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