The genetic material, DNA, which is referred to as the 'blue print of life', enfolds within it all the information that goes into the making of an individual
It is a well-known fact that the human body is made up of millions of cells. What is fascinating is that these cells contain structures called chromosomes, which are made up of deoxyribonucleic acid (DNA), which has been identified as the 'blue- print of life'. Segments of DNA, called genes, determine the inheritance of the physical and emotional traits in all organisms; in other words, they govern all aspects of all the creatures on earth.
The number of chromosomes present in a cell is specific for a particular species. Humans have 46 chromosomes, which occur in pairs, one set of 23 chromosomes derived from the mother and the other set derived from the father. The sperm and the egg contain only 23 chromosomes each. Fertilization of the egg and sperm restores the original number to 46.
The eggs produced by a female contain only the X chromosome while sperms can carry either an X or a Y chromosome. So when the X chromosome of the mother's egg unites with the father's sperm carrying a X chromosome, it results in a girl child (XX). On the contrary, when an egg containing X chromosome fuses with a Y chromosome bearing sperm, it gives rise to a male child (XY). Therefore, the sex determination of a child is dependent on the father and not on the mother.