Question

In human beings, the statistical probability of getting either a male or female child is 50 : 50. Give a suitable explanation.

Answer 1

In human beings, males possess two sex chromosomes (X and Y) so they produce two types of male gametes - 50% sperms with X chromosome and 50% sperms with Y chromosome. So, the sex of the child is determined by the sex chromosome present in the male gamete or sperm. Since the ratio of male gametes containing X chromosome and those containing Y chromosome is 50 : 50, the statistical probability of male or a female infant is also 50 : 50.