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(c) Sex determination in the unborn baby.

 

Answer

Sex of an unborn baby is determined when the egg cells of the women gets fertilized by the sperm cells of man and pregnancy takes place.

Sex chromosomes are present in the nuclei of each cell

  • Male sperm has 2 sex chromosomes X and Y
  • Female egg has 2 sex chromosomes X and X


When both fertilize,

X Chromosome of Male + X Chromosome of Female → XX Chromosome of Zygote ( Female )

Y Chromosome of Male + X Chromosome of Female → XY Chromosome of Zygote ( Male )

female-(xx)-male-(xy)-child---teachoo.jpg

So sex of child is dependent upon father not mother(as fathers chromosome can be X or Y but mother is always X)

 

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CA Maninder Singh is a Chartered Accountant for the past 14 years and a teacher from the past 18 years. He teaches Science, Economics, Accounting and English at Teachoo