Question

What will happen, if the sperm containing ${}^{\prime }{X}^{\prime }$ chromosomes fertilises the Ovum?

• A. Female child born
• B. Male child born
• C. Can not guess
• D. None

Answer 1

The correct option is A Female child born

The process of fusion of a sperm with an ovum is called fertilisation. During fertilisation, a sperm comes in contact with the zona pellucida layer of the ovum and induces changes in the membrane which blocks entry of additional sperms. This also induces the formation of the haploid secondary oocyte, by meiotic division, which fuses with sperm to form zygote. At this stage the sex of the baby is determined. Males have XY chromosomes so sperms who have haploid no. of chromosomes carry either X or Y. While females have XX chromosomes, so all ovum will carry X chromosome. So when a sperm containing X chromosome fertilises an ovum, a zygote with XX chromosomes is formed. Thus a female child is born.