Sexual characteristics are physical traits of an organism (typically of a sexually dimorphic organism) which are indicative of its biological sex. These include both primary sex characteristics and secondary sex characteristics. Humans In humans, sex organs or primary sexual characteristics, which are those a person is born with, can be distinguished from secondary sex characteristics, which develop later in life, usually during puberty. The development of both is controlled by sex hormones produced by the body after the initial fetal stage where the presence or absence of the Y-chromosome and/or the SRY gene determine development. Hormones that express sexual differentiation in humans include: estrogens progesterone androgens such as testosterone Typical sexual characteristics The following table lists the typical sexual characteristics in humans (even though some of these can also appear in other animals as well): Other organisms In invertebrates and plants, hermaphrodites (which have both male and female reproductive organs either at the same time or during their life cycle) are common, and in many cases, the norm. In other varieties of multicellular life (e.g. the fungi division, Basidiomycota) sexual characteristics can be much more complex, and may involve many more than two sexes. For details on the sexual characteristics of fungi, see: Hypha and Plasmogamy. See also Mammalian gestation Reproduction Sex and gender distinction Sexual differentiation References Sexual anatomy