Sex steroids, also known as gonadal steroids, are steroid hormones that interact with vertebrate androgen or estrogen receptors. Steroid hormones are Steroids which act as Hormones Mammalian steroid hormones can be grouped into five groups by the receptors to which they bind Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes Androgen is the generic term for any natural or synthetic compound usually a Steroid Hormone, that stimulates or controls the development and maintenance of masculine Estrogens (US otherwise oestrogens or œstrogens) are a group of Steroid compounds named for their importance in the Estrous cycle, In Biochemistry, a receptor is a Protein molecule embedded in either the Plasma membrane or Cytoplasm of a cell to which a mobile signaling The term sex hormone nearly always is synonymous with sex steroid.

Contents 1 Production 2 Functions 3 Synthetic sex steroids 4 Types 5 See also 6 References 7 External links

Production

Natural sex steroids are made by the gonads (ovaries or testes), by adrenal glands, or by conversion from other sex steroids in other tissue such as liver or fat. The gonad is the organ that makes Gametes The gonads in males are the Testes and the gonads in Females are the Ovaries. "Ovaria" redirects here This is also a proposed section and a Synonym of Solanum. The testicle (from Latin testiculus, diminutive of testis, meaning "witness" virility plural testes) is the male In Mammals the adrenal glands (also known as suprarenal glands) are the triangle-shaped Endocrine glands that sit on top of the Kidneys their

Functions

Sex steroids play important roles in inducing the body changes known as primary sex characteristics and secondary sex characteristics. A sex organ, or primary sexual characteristic, as narrowly defined is any of the anatomical parts of the body which are involved in sexual reproduction and constitute Secondary sex characteristics are traits that distinguish the two Sexes of a species but that are not directly part of the Reproductive system.

The development of both primary and secondary sexual characteristics is controlled by sex hormones after the initial fetal stage where the presence or absence of the Y-chromosome and/or the SRY gene determine development. An organism's sex is defined by the gametes it produces males produce male gametes (spermatozoa or Sperm) while females produce female gametes (ova or Egg cells; individual The Y chromosome is the sex-determining Chromosome in most Mammals including Humans In mammals it contains the gene SRY, which triggers SRY ( Sex-determining Region Y) is a Sex -determining Gene on the Y chromosome in the Therians (placental mammals and marsupials

Synthetic sex steroids

There are also many synthetic sex steroids. Synthetic androgens are often referred to as anabolic steroids. Anabolic steroids, or anabolic-androgenic steroids ( AAS) are a class of Steroid hormones related to the hormone Testosterone. Synthetic estrogens and progestins are used in methods of hormonal contraception. Hormonal contraception refers to Birth control methods that act on the hormonal system Ethinylestradiol is a semi-synthetic estrogen. Ethinylestradiol, also ethinyl estradiol (EE is a Derivative of Estradiol.

Types

In many contexts, the two main classes of sex steroids are androgens and estrogens, of which the most important human derivatives are testosterone and estradiol, respectively. Testosterone is a Steroid hormone from the Androgen group In mammals testosterone is primarily secreted in the testes of males and the Ovaries Estradiol (17β-estradiol (also oestradiol) is a Sex hormone. Other contexts will include progestagen as a third class of sex steroids, distinct from androgens and estrogens. Progestagens (also spelled progestogens or gestagens) are Hormones that produce effects similar to those of Progesterone, the only natural progestagen Progesterone is the most important and only naturally-occurring human progestagen. Progesterone is a C-21 Steroid Hormone involved in the Female Menstrual cycle, Pregnancy (supports Gestation In general, androgens are considered "male sex hormones", since they have masculinizing effects, while estrogens and progestagens are considered "female sex hormones"^[1] although all types are present in each gender, albeit at different levels.

Sex steroids include:

• androgens:
  • testosterone
  • androstenedione
  • dihydrotestosterone
  • dehydroepiandrosterone
  • anabolic steroids

• estrogens:
  • estradiol
  • estrone

• progestagens:
  • progesterone
  • progestins

See also

• Klinefelter's syndrome
• Androgen insensitivity syndrome
• Sex-hormone therapy

References

penis

External links

• MeSH Sex+Steroid+Hormones
• Sex+hormones at eMedicine Dictionary

Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books eMedicine is an online clinical medical knowledge base that was founded in 1996 by Scott Plantz and Richard Lavely two medical doctors

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