Updated by: Arabinda Naik
There are two types of chromosomes in the diploid cells. Autosomes bearing genes for somatic characters and sex chromosomes bearing genes for sex. Sex chromosomes also carry some genes of non-sexual characters such as colour blindness, haemophilia. Such genes are always associated with sex chromosomes called sex linked genes. Human has many more genes on the X chromosomes than on the Y chromosome. There are many more X linked characters than Y linked. In female it is homogametic with two XX chromosomes, while in male it is heterogametic with one X chromosomes. The male is hemizygous because it has half the number of X chromosomes. Genes on the X or Y chromosome are called sex linked genes and their mode of inheritance is called sex linked inheritance.