| | Definition: | | A sex chromosome found in all birds and certain other animals where the female is the heterogametic sex. It is part of the WZ set of sex chromosomes, which are so designated to prevent confusion with the XY set of sex chromosomes for species where the male is the heterogametic sex. In the WZ system, the male has two Z chromosomes and the female has only one (and one W chromosome). |
Biology Dictionary