Describe sex determination in the human beings.

Explanation

The sex determination in human beings is due to chromosomes and thus it is genetically determined.
Human beings have 23 pairs of chromosomes. Each pair has one maternal and one paternal copy.
`rarr` 22 pairs of chromosomes are similar in both male and female. They are called autosomes, as they decide body characters.
`rarr` 23rd pair has sex chromosomes.
`rarr` Women have a pair of X chromosomes, i.e., females are therefore XX.
`rarr` Men have a mismatched pair in which one is normal sized X while the other is a short one called Y, i.e., Males are therefore XY.

As shown in figure, the probability of getting a male (boy) or a female (girl) child is `50%`.
All children will inherit an X-chromosome from their mother regardless of whether they are boys or girls.
Thus, the sex of the children will be determined by what they inherit from their father.
A child who inherits an X-chromosome from father will be girl and one who inherits a Y-chromosome from father will be a boy.