Gender
(sex) is a set of morphological and physiological characteristics of the
organism underlying sexual reproduction, the essence of which is reduced to
fertilization, i.e. the fusion of male and female gametes (gametes) zygote,
which develops into a new organism.Sexual reproduction of a species is
considered as one of the mechanisms of its homeostasis. Thanks to this
mechanism, numerous species have an evolutionary advantage.
In
the book, two authors will discuss the types of genetic sex determination and
differentiation, mostly in multicellular animal organisms. Sex determination is
both genetic and environmental process, the sex of an individual being
established through an alternative physiological solution. There are two main
postulated mechanisms of sex determination: genetic (GSD, Genetical Sex
Determination) and environmental (ESD, Environmental Sex Determination).