Sexual characteristics are physical traits of an
organism (typically of a
sexually dimorphic organism) which are indicative of or resultant from biological
sexual factors. These include both
primary sex characteristics, such as
gonads, 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.
Male primary sex characteristics are the penis, the scrotum and the ability to
ejaculate when matured. Female primary sex characteristics are the vulva, vagina, uterus, fallopian tubes, cervix, and the ability to give
birth and
menstruate when matured.
Hormones that express sexual differentiation in humans include:
*
estrogens such as
estradiol
*
progestogens such as
progesterone
*
androgen
An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...
s such as
testosterone
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
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...
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.
Secondary sex characteristics in non-human animals include manes of male
lion
The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'', native to Sub-Saharan Africa and India. It has a muscular, broad-chested body (biology), body; a short, rounded head; round ears; and a dark, hairy tuft at the ...
s, long tail feathers of male
peafowl, the tusks of male
narwhals, enlarged
proboscises in male
elephant seals and
proboscis monkeys, the bright facial and rump coloration of male
mandrills, and horns in many
goats and
antelopes.
See also
*
Mammalian gestation
*
Reproduction
*
Sex and gender distinction
*
Sexual differentiation
References
{{Authority control
Sexual anatomy