Question

fill the blank circles in figure 10.1 and identify the sex of child a and b​

Answer 1

Therefore, the sex of child A and B are respectively Feminine and Masculine.

Answer 2

The sex of the child A and B are given as follows:

A - XX → girl/female  B - XY → boy/male

• The 2 circles from the 2 parents respectively represent the gametes formed from the 2 parents.
• The gametes receive half the number of chromosomes from diploid parent specialized cell.
• X and Y represent the sex chromosomes.
• 22 pairs of autosomes (non - sex chromosomes) + XX = female.
• 22 pairs of autosomes + XY = male.
• Each gamete receives a single copy of each autosome i.e. 22 autosomes and 1 sex chromosome.
• Therefore, The first blank circle under female "XX" is the gamete containing the X chromosome represented by "X".
• The other blank circle under the male "XY" is the gamete containing the Y Chromosome represented by "Y".
• Sex is determined by the sex chromosome received from the male parent by the offspring. If it is X then it is a female; if it is Y then it is a male.
• Child "A" receives 1X from the mother and 1X from the father, therefore, Circle "A" is "XX".
• Child "B" receives 1X from the mother (child always receives an X chromosome from the mother) and 1Y from the father, therefore, Circle "B" is "XY".