Medel obtained the following types of seeds after self-pollination in pea plants with round, yellow seeds.

Examine the outcome and explain the inheritance mechanism that produced it.

                                                           (OR)

Explain why in humans, the probability of a newborn baby being a boy is 50% and newborn baby being a girl is 50% with the help of the mechanism of sex determination in human beings.

The obtained ratio is 9: 3: 3: 1, in which both parental and new combinations are seen. This shows that the genes of the progeny plants were not entirely inherited from each parent. From the pair of maternal and paternal chromosomes, each germ cell takes one chromosome. One pair of characters can separate from another pair of characters independently when two germ cells join.

                                                          (OR)

Humans inherit their parents' genes, which determine whether they will be male or female. The sex chromosomes are perfectly matched in females (XX). However, men have an unbalanced pair of chromosomes (XY). Regardless of whether they are boys or girls, all children receive an X chromosome from their mother. As a result, the children's sex will depend on what they inherit from their fathers. A girl will be born if her father gave her an X chromosome, and a boy will be born if he gave her a Y chromosome.

Hence, in humans, there is a 50 % probability of the birth of a boy and a 50 %probability that girls will be born.