Labelled diagram of Sex determination in Human beings
In human beings, a person’s gender is largely determined genetically. In other words, the genes we inherit from our parents determine whether we will be boys or girls. But so far, we have assumed that same set of genes is inherited from both parents. This explains the fact that bot all human chromosomes are linked. Most human chromosomes have a maternal and parental copy, and we have 22 such pairs. But one pair, called a sex chromosome, is always strange in that it is not a perfect pair. Females have a perfect pair of sex chromosomes, both called Xs. But males have a mismatched pair in which one has a normal sized X while the other has a smaller Y. So females are XX, while males are XY. Half will be boy and half will be girls from the children. All children will inherit the X chromosome from their mother whether they are boys or girls. Thus, the gender of children will be determined by the inheritance they receive from their father. The child who inherits the X chromosome from her father will be a girl and the one who inherits the Y chromosome from him will be a boy.
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