(b) The sex of a newborn depends on what happens at the time of fertilization.
(i) If a sperm carrying X chromosome fertilizes the ovum carrying X chromosome, then the girl child will be born and the child will have XX combination of sex chromosomes.
(ii) If a sperm carrying Y chromosome fertilizes the ovum carrying X chromosome, then the child born will The above presentation clearly shows that it is matter of chance whether the newborn will be boy or girl and none of the parents may be considered responsible for it.be a boy and the child will have XY combination of sex chromosome. The above presentation clearly shows that it is matter of chance whether the newborn will be boy or girl and none of the parents may be considered responsible for it.