Question

The probability that a baby will be a boy is ½ as is the probability that a baby will be a girl. Explain this fact by explaining the mechanism of meiosis in the production of gametes and the process of fertilization. If a family has 4 boys and 3 girls, what is the probability that the next child will be a girl?

Answer 1

The cross between the sex chromosomes i.e. the XX female and the XY male will have the offspring with the following genotypes and probabilities.

XX* XY = XX, XY, XX, XY

Means, the chances of having a female is ½ and the chances of having a male is also ½. Thus, during the fertilization process have the equal probabilities of resulting in a male or female.

If a family has 4 boys and 3 girls, the probability that the next child will be a girl is ½. This is because every time, the probability of having a male or female child is 50%.