WordNet

for or pertaining to or composed of women or girls; "the female lead in the play"; "a female chorus"
an animal that produces gametes (ova) that can be fertilized by male gametes (spermatozoa)
a person who belongs to the sex that can have babies (同)female person
characteristic of or peculiar to a woman; "female sensitiveness"; "female suffrage" (同)distaff
being the sex (of plant or animal) that produces fertilizable gametes (ova) from which offspring develop; "a female heir"; "female holly trees bear the berries"
of or relating to the external sex organs; "genital herpes"; "venereal disease" (同)venereal
external sex organ (同)genital_organ, genitals, private_parts, privates, crotch

PrepTutorEJDIC

(動植物について)『雌の』 / (特に性を区別して)『女の』,女性の / (ねじ・差し込みなど)雌の / 『雌』;(性別上の)『女性』 / 《話》女性,婦人
生殖の,生殖器の
=genitals

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/10/23 14:17:33」(JST)

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The sex organs of a green alga, Chara are the male antheridia (red) and female archegonia (brown).

A sex organ or primary sexual characteristic, as narrowly defined, is any anatomical part of the body involved in sexual reproduction and constituting the reproductive system in a complex organism, especially the external sex organs; the external sex organs are also commonly referred to as the genitalia or genitals.^[1]^[2]

Mosses, ferns, and some similar plants have gametangia for reproductive organs, which are part of the gametophyte.^[3] The flowers of flowering plants produce pollen and egg cells, but the sex organs themselves are inside the gametophytes within the pollen and the ovule.^[4] Coniferous plants likewise produce their sexually reproductive structures within the gametophytes contained within the cones and pollen. The cones and pollen are not themselves sexual organs.

Terminology

The Latin term genitalia, sometimes anglicized as genitals, is used to describe the externally visible sex organs, known as primary genitalia or external genitalia: in male mammals, the penis and scrotum; and in female mammals, the clitoris and vulva.

The other, hidden sex organs are referred to as the secondary genitalia or internal genitalia. The most important of these are the gonads, a pair of sex organs, specifically the testes in the male or the ovaries in the female. Gonads are the true sex organs, generating reproductive gametes containing inheritable DNA. They also produce most of the primary hormones that affect sexual development, and regulate other sexual organs and sexually differentiated behaviors.

In general zoology, given the great variety in organs, physiologies, and behaviors involved in copulation, male genitalia are more strictly defined as "all male structures that are inserted in the female or that hold her near her gonopore during sperm transfer"; female genitalia are defined as "those parts of the female reproductive tract that make direct contact with male genitalia or male products (sperm, spermatophores) during or immediately after copulation".^[5]

Mammals

External and internal organs

The visible portion of the mammalian genitals for males consists of the scrotum and penis; for females, it consists of the labia, clitoris, and vagina.

In placental mammals, females have two genital orifices, the vagina and urethra, while males have only one, the urethra.^[6] Male and female genitals have many nerve endings, resulting in pleasurable and highly sensitive touch.^[7]^[8] In most human societies, particularly in conservative ones, genitals are considered a public indecency and sometimes even illegal if left uncovered in public.^[9]

In mammals, sex organs include:

Female	Male
Bartholin's glands Cervix Clitoris Clitoral frenulum Clitoral glans (glans clitoridis) Clitoral hood Fallopian tubes Labia Labia majora Labia minora Frenulum of labia minora Ovaries Skene's gland Uterus Vagina Vulva An image of human female external sex organs (shaved pubic hair)	Bulbourethral glands Epididymis Penis Foreskin Frenulum of penis Glans penis Prostate Scrotum Seminal vesicles Testicles An image of human male external sex organs

Development

In typical prenatal development, sexual organs originate from a common anlage anatomy during early gestation and differentiate into male or female variations. The SRY gene, usually located on the Y chromosome and encoding the testis determining factor, determines the direction of this differentiation. The absence of it allows the gonads to continue to develop into ovaries.

Thereafter, the development of the internal reproductive organs and the external genitalia is determined by hormones produced by certain fetal gonads (ovaries or testes) and the cells' response to them. The initial appearance of the fetal genitalia (a few weeks after conception) looks basically feminine: a pair of "urogenital folds" with a small protuberance in the middle, and the urethra behind the protuberance. If the fetus has testes, and if the testes produce testosterone, and if the cells of the genitals respond to the testosterone, the outer urogenital folds swell and fuse in the midline to produce the scrotum; the protuberance grows larger and straighter to form the penis; the inner urogenital swellings grow, wrap around the penis, and fuse in the midline to form the penile urethra.

Each sexual organ in one sex has a homologous counterpart in the other one. See a list of homologues of the human reproductive system. In a larger perspective, the whole process of sexual differentiation also includes development of secondary sexual characteristics such as patterns of pubic and facial hair and female breasts that emerge at puberty. Furthermore, differences in brain structure arise, affecting, but not absolutely determining, behavior.

Intersex is the development of genitalia somewhere between typical male and female genitalia. Once the child is born, the parents are faced with decisions that are often difficult to make, such as whether or not to modify the genitalia, assign the child as male or female, or leave the genitalia as is. Some parents allow their doctors to choose. If they do decide to modify the genitalia, they have approximately a 50% chance of getting genitalia that will match the child's gender identity. If they pick the wrong one, their child may begin to show symptoms of transsexualism, which can lead them to a life of discomfort until they are able to remedy the issue.^[10]

Because of the strong sexual selection affecting the structure and function of genitalia, they form an organ system that evolves faster that any other.^[11] A great variety of genital form and function may therefore be found among animals.

Plants

The life cycle of land plants involves alternation of generations between a sporophyte and a haploid gametophyte. The gametophyte produces sperm and/or egg cells by mitosis. The sporophyte produces spores by meiosis which in turn develop into gametophytes. Any sex organs that are produced by the plant will develop on the gametophyte. The seed plants, which include conifers and flowering plants have small gametophytes that develop inside the pollen grains (male) and the ovule (female).

Flowering plants

Sexual reproduction in flowering plants involves the union of the male and female germ cells, sperm and egg cells respectively. Pollen is produced in stamens, and is carried to the pistil, which has the ovary at its base where fertilization can take place. Within each pollen grain is a male gametophyte which consists of only three cells. In most flowering plants the female gametophyte within the ovule consists of only seven cells. Thus there are no sex organs as such.

References

^ "Sex organ (sɛks ˈɔːɡən)". Collins English Dictionary. Retrieved September 14, 2013.
^ P. R. Ashalatha, G. Deepa (2012). Textbook of Anatomy and Physiology for Nurses. JP Medical Ltd. pp. 252–274. ISBN 9350254239. Retrieved September 14, 2013.
^ "Mosses and Ferns". Biology.clc.uc.edu. 2001-03-16. Retrieved 2012-08-01.
^ "Flowering Plant Reproduction". Emc.maricopa.edu. 2010-05-18. Retrieved 2012-08-01.
^ Eberhard, W.G., 1985. Sexual Selection and Animal Genitalia. Harvard University Press
^ Marvalee H. Wake (15 September 1992). Hyman's Comparative Vertebrate Anatomy. University of Chicago Press. p. 583. ISBN 978-0-226-87013-7. Retrieved 6 May 2013.
^ Sexual Intimacy in Marriage William Cutrer
^ Daphne's Dance: True Tales in the Evolution of Woman's Sexual Awareness Brigitta Olsen
^ Unpopular Privacy: What Must We Hide? retrieved 9 February 2012
^ Fausto Sterling, Anne (2000). Sexing The Body. New York: New York. pp. 44–77.
^ Schilthuizen, M. 2014. Nature's Nether Regions: What the Sex Lives of Bugs, Birds, and Beasts Tell Us About Evolution, Biodiversity, and Ourselves. Penguin USA

UpToDate Contents

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1. 小児における身体的診察：会陰 the pediatric physical examination the perineum
2. 小陰唇肥大症 labia minora hypertrophy
3. 小児および思春期における性的虐待の評価 evaluation of sexual abuse in children and adolescents
4. 熱傷再建の原理：会陰および生殖器 principles of burn reconstruction perineum and genitalia
5. 女性における下部生殖器外傷の評価およびマネージメント evaluation and management of lower genital tract trauma in women

English Journal

Morphology of the external genitalia of the adult male and female mice as an endpoint of sex differentiation.

Weiss DA, Rodriguez E Jr, Cunha T, Menshenina J, Barcellos D, Chan LY, Risbridger G, Baskin L, Cunha G.SourceDivision of Pediatric Urology, University of California, San Francisco Children's Hospital, San Francisco, CA 94143, USA.
Molecular and cellular endocrinology.Mol Cell Endocrinol.2012 May 6;354(1-2):94-102. Epub 2011 Aug 27.
Adult external genitalia (ExG) are the endpoints of normal sex differentiation. Detailed morphometric analysis and comparison of adult mouse ExG has revealed 10 homologous features distinguishing the penis and clitoris that define masculine vs. feminine sex differentiation. These features have enabl
PMID 21893161

Hyal-1 but not Hyal-3 deficiency has an impact on ovarian folliculogenesis and female fertility by altering the follistatin/activin/Smad3 pathway and the apoptotic process.

Dumaresq-Doiron K, Edjekouane L, Orimoto AM, Yoffou PH, Gushulak L, Triggs-Raine B, Carmona E.SourceMaisonneuve-Rosemont Hospital Research Center, Montreal, Quebec, Canada.
Journal of cellular physiology.J Cell Physiol.2012 May;227(5):1911-22. doi: 10.1002/jcp.22919.
Ovarian follicle development is a process regulated by various endocrine, paracrine and autocrine factors that act coordinately to promote follicle growth. However, the vast majority of follicles does not reach the pre-ovulatory stage but instead, undergo atresia by apoptosis. We have recently descr
PMID 21732362