Sex - Sex Determination

Sex Determination

The most basic sexual system is one in which all organisms are hermaphrodites, producing both male and female gametes—this is true of some animals (e.g. snails) and the majority of flowering plants. In many cases, however, specialization of sex has evolved such that some organisms produce only male or only female gametes. The biological cause for an organism developing into one sex or the other is called sex determination.

In the majority of species with sex specialization, organisms are either male (producing only male gametes) or female (producing only female gametes). Exceptions are common—for example, in the roundworm C. elegans the two sexes are hermaphrodite and male (a system called androdioecy).

Sometimes an organism's development is intermediate between male and female, a condition called intersex. Sometimes intersex individuals are called "hermaphrodite"; but, unlike biological hermaphrodites, intersex individuals are unusual cases and are not typically fertile in both male and female aspects.

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Other articles related to "sex determination, sex, determination":

Crocodilia - Description - Internal Organs
... Crocodilian sex determination is temperature-dependent i.e ... the sex of developing crocodilians is determined by the incubation temperature of the eggs ... This means crocodilians do not have genetic sex determination, but instead have a form of environmental sex determination which is based upon the temperature embryos are subjected to early in their development ...
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Temperature-dependent Sex Determination
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