60. What determines the sex of a child?
Sometimes we wonder as to why all the people in the world are not of
one sex. How does one become a boy or a girl? Actually, the female
body produces an egg called ovum every month. If this ovum is
fertilized by the sperm of a male, an embryo is formed which
develops into a child in the mother's womb.
The ovum and the sperm contain sex chromosomes which are
responsible for making us look like our parents. There are two types
of sex chromosomes X and Y. The female ovum contains two X
chromosomes, while the male sperm carries XY chromosomes. If the
ovum is fertilized by the X chromosome of the sperm, a girl is born
and if the ovum is fertilized by a Y chromosome, a boy is born.
Điều gì xác định giới tính của một
đứa trẻ?
Đôi khi chúng ta ngạc nhiên là vì sao tất cả mọi người trên
thế giới không phải là cùng một giới tính. Vì sao một đứa
