This arrangement means that it is the male (Y chromosome) that determines the sex of the male offspring when fertilization occurs in the woman’s womb.

The Y chromosome is one of two sex-determining chromosomes (allosomes) in mammals, including humans.

In mammals, the Y chromosome contains the gene SRY, which triggers testicle development if present. 

The human Y chromosome is composed of about 50 million base pairs. DNA in the Y chromosome is passed from father to son, and Y-DNA analysis may thus be used in genealogical research.

With a 30% difference between humans and chimpanzees, the Y chromosome is one of the fastest evolving parts of the human genome.

The male sperm contains a Y and X chromosome:

In the process of sexual intercourse (when a man and woman are having sex), during orgasm of the male, if the Y chromosome reaches the female ovum egg cell first, then the child will be a boy. 

If the x chromosome reaches the egg cell first, then child will likely become a girl.

Article written by Conscious lifestyle