People are Dioecious i.e. include female and male gonads in various induviduals.Male Gonads produce sperms and the female gametes produce Ovum. Lower animals advertisement plants are normally Monoecious.
The chromosomes which assist in decision of the sex of the offspring are called the Allosomes or Sex Chromosomes. Whereas the vegtative chromosomes which are not useful in sex are called the Autosomes.
The approach of sex decision in Human Beings is XY type, where in males, the Allosomes are XY type and in women the allosomes are XX
type. Human beings include 46 chromosomes in the nucleus of the cell out of which, 44 are autosomes and other 2 are allosomes.
On production of gametes, the no. of chromosomes is minimized to half, i.e. in the gametes there are 23 chromosomes. The type of chromosomes is not very same.
In women, ova includes 22 autosomes and 1 X chromosome.
In males, the sperm consists of 22 autosomes as in ovum however the allosome can be either X or Y type, i.e. a sperm can consist of either X or Y alloome.
Throughout fertilisation, if sperm with X allosome merges with the ovum, then it results into development of female offspring (XX) and if Y allosome of male merges with the ovum, then it results to the development of Male offspring (XY).
Hence, Ovum has no function in sex decision however the sperm has the function of sex decision in people, i.e. if sperm has X allosome, offspring is female and if Y allosome exists, offspring if male.
On production of gametes, the no. The type of chromosomes is not very same.