X And Y Chromosomes

Dictionary of Biological Psychology

Non-autosomal CHROMOSOMES (see AUTOSOMAL CHROMO SOME) in the CELL nucleus of sexually reproducing organisms, which determine the sex of the organism (hence they are also known as SEX CHROMOSOMES).

Females have two X chromosomes, whereas males have one X and one Y chromosome. Since each organism receives one sex chromosome from each parent, it will receive an X chromosome from the mother, and either an X or Y chromosome from the father. Thus the type of sex chromosome present in the gamete from the father (see GAMETES) will determine the sex of the offspring.

FIONA M.INGLIS