The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila) and some plants (Ginkgo). In this system, females have two of the same kind of sex chromosome (XX), and are called the homogametic sex. Males have two distinct sex chromosomes (XY), and are called the heterogametic sex.
This system is in contrast with the ZW sex-determination system found in birds, some insects, many reptiles and other animals, in which the heterogametic sex is female.
There is also a temperature-dependent sex determination system is found in some reptiles.
Read more about XY Sex-determination System: Mechanisms, Recent Studies On The Genetic Factors That Influence Gender Traits
Famous quotes containing the word system:
“We recognize caste in dogs because we rank ourselves by the familiar dog system, a ladderlike social arrangement wherein one individual outranks all others, the next outranks all but the first, and so on down the hierarchy. But the cat system is more like a wheel, with a high-ranking cat at the hub and the others arranged around the rim, all reluctantly acknowledging the superiority of the despot but not necessarily measuring themselves against one another.”
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