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Ovotestes
An ovotestis is a gonad with both testicular and ovarian aspects. In humans, ovotestes are an infrequent anatomical variation associated with gonadal dysgenesis. The only mammals where ovotestes are not symptomatic of an intersex variation are moles, wherein females possess ovotestes along with a masculinized clitoris. These ovotestes in nonpregnant female moles secrete eight times as much testosterone as the ovotestes of pregnant moles. In invertebrates that are normally hermaphroditic, such as most gastropods (snails and slugs) in the clade Eupulmonata, an ovotestis is a common feature of the reproductive anatomy. In mice, ovotestes are structured such that the central region is testicular tissue while the poles both contain ovarian tissue. Experiments involving the SOX9 gene, which is initiated by the SRY region of the Y chromosome, have shown the gene’s requirement for testicular differentiation from the presence of ovotestis formation within XX Sox9 trangenic mice. (6) Ov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clitoris
The clitoris ( or ) is a female sex organ present in mammals, ostriches and a limited number of other animals. In humans, the visible portion – the glans – is at the front junction of the labia minora (inner lips), above the opening of the urethra. Unlike the penis, the male homologue (equivalent) to the clitoris, it usually does not contain the distal portion (or opening) of the urethra and is therefore not used for urination. In most species, the clitoris lacks any reproductive function. While few animals urinate through the clitoris or use it reproductively, the spotted hyena, which has an especially large clitoris, urinates, mates, and gives birth via the organ. Some other mammals, such as lemurs and spider monkeys, also have a large clitoris. The clitoris is the human female's most sensitive erogenous zone and generally the primary anatomical source of human female sexual pleasure. In humans and other mammals, it develops from an outgrowth in the embry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
True Hermaphroditism
True hermaphroditism, sometimes referred to as ovotesticular syndrome, is an intersex condition in which an individual is born with both ovarian and testicular tissue. Commonly, one or both gonad A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sper ...s is an ovotestis containing both types of tissue. Although it is similar in some ways to mixed gonadal dysgenesis, the conditions can be distinguished histologically. Symptoms * Gynecomastia (present in 75% of cases.) History The first medical attempts to document cases appeared in the 16th century. Up until the Late Middle Ages individuals with these conditions were viewed as monsters. Causes There are several ways in which this may occur. * It can be caused by the division of one ovum, followed by fertilization of each haploid o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphroditic
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species (called trioecy); these three systems are so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonad
A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sperm in the form of spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes are haploid cells. Some hermaphroditic animals have a type of gonad called an ovotestis. Evolution It is hard to find a common origin for gonads, but gonads most likely evolved independently several times. Regulation The gonads are controlled by luteinizing hormone and follicle-stimulating hormone, produced and secreted by gonadotropes or gonadotrophins in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone produced in the hypothalamus. Development Gonads start developing as a common primordium (an organ in the earliest stage of development), in the form of genital ridges, which are only l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malacological Newsletter
Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca (mollusks or molluscs), the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, and cephalopods, along with numerous other kinds, many of which have shells. One division of malacology, conchology, is devoted to the study of mollusk shells. Malacology derives . Fields within malacological research include taxonomy, ecology and evolution. Applied malacology studies medical, veterinary, and agricultural applications; for example, mollusks as vectors of disease, as in schistosomiasis. Archaeology employs malacology to understand the evolution of the climate, the biota of the area, and the usage of the site. In 1681, Filippo Bonanni wrote the first book ever published that was solely about seashells, the shells of marine mollusks. The book was entitled: In 1868, the German Malacological Society was founded. Zoolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intersex
Intersex people are individuals born with any of several sex characteristics including chromosome patterns, gonads, or genitals that, according to the Office of the United Nations High Commissioner for Human Rights, "do not fit typical binary notions of male or female bodies". Sex assignment at birth usually aligns with a child's anatomical sex and phenotype. The number of births with ambiguous genitals is in the range of 1:2000–1:4500 (0.022%–0.05%). Other conditions involve atypical chromosomes, gonads, or hormones. Some persons may be assigned and raised as a girl or boy but then identify with another gender later in life, while most continue to identify with their assigned sex. The number of births where the baby is intersex has been reported differently depending on who reports and which definition of intersex is used. Anne Fausto-Sterling and her co-authors suggest that the prevalence of "nondimorphic sexual development" might be as high as 1.7%. A study publish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anton Krzyzanowski
Anton Krzyzanowski or Anton Kryzhanovsky (, born 3 March 1995) is a Russian intersex activist and sound designer. He is the founder of the intersex human rights initiative group Interseks.ru () and is known for speaking openly about living with ovotestis. Early life Krzyzanowski was born in a small town in Ural, Russia. He was assigned female at birth based on the appearance of his genitals but, when he was 13 years old, he went through puberty according to the male pattern. He showed male secondary sex characteristics: his voice broke, he developed facial hair, and did not start menstruating. Because of his religious family, in 2010 Krzyzanowski was sent to a monastery as family members believed that "demons were sitting in him." Krzyzanowski has stated that he was advised to pray in order to be "cured" and become a "normal" woman. When he was 15 years old, he was sent to the hospital due to intense stomach pains; the priests suspected that it was the result of not menstruat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornu Aspersum
''Cornu aspersum'' (syn. ''Cryptomphalus aspersus''), known by the common name garden snail, is a species of land snail in the family Helicidae, which includes some of the most familiar land snails. Of all terrestrial molluscs, this species may well be the most widely known. It was classified under the name ''Helix aspersa'' for over two centuries, but the prevailing classification now places it in the genus ''Cornu''. The snail is relished as a food item in some areas, but it is also widely regarded as a pest in gardens and in agriculture, especially in regions where it has been introduced accidentally, and where snails are not usually considered to be a menu item. Description The adult bears a hard, thin calcareous shell in diameter and high, with four or five whorls. The shell is variable in coloring and shade of color, but generally it has a reticulated pattern of dark brown, brownish-golden, or chestnut with yellow stripes, flecks, or streaks (characteristically interr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproductive System Of Gastropods
The reproductive system of gastropods (slugs and snails) varies greatly from one group to another within this very large and diverse taxonomic class of animals. Their reproductive strategies also vary greatly, see Mating of gastropods. In many marine gastropods there are separate sexes (male and female); most terrestrial gastropods however are hermaphrodites. Courtship is a part of the behaviour of mating gastropods. In some families of pulmonate land snails, one unusual feature of the reproductive system and reproductive behavior is the creation and utilization of love darts, the throwing of which has been identified as a form of sexual selection. Gastropods are defined as snails and slugs, belonging to a larger group called Molluscs. Gastropods have unique reproductive systems, varying significantly from one taxonomic group to another. They can be separated into three categories: marine, freshwater, and land. Reproducing in marine or freshwater environments makes getting s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testis-determining Factor
Sex-determining region Y protein (SRY), or Testis-determining factor (TDF), is a DNA-binding protein (also known as gene-regulatory protein/transcription factor) encoded by the ''SRY'' gene that is responsible for the initiation of male sex determination in therian mammals (placental mammals and marsupials). SRY is an intronless sex-determining gene on the Y chromosome. Mutations in this gene lead to a range of disorders of sex development with varying effects on an individual's phenotype and genotype. TDF is a member of the SOX (SRY-like box) gene family of DNA-binding proteins. When complexed with the SF1 protein, TDF acts as a transcription factor that causes upregulation of other transcription factors, most importantly SOX9. Its expression causes the development of primary sex cords, which later develop into seminiferous tubules. These cords form in the central part of the yet-undifferentiated gonad, turning it into a testis. The now-induced Leydig cells of the testi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomphalaria Glabrata Ovotestis
''Biomphalaria'' is a genus of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails and their allies.MolluscaBase (2018). Biomphalaria Preston, 1910. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=718742 on 2018-02-13 ''Biomphalaria'' is the type genus of the tribe Biomphalariini. ''Taphius'' is a synonym for ''Biomphalaria''. The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral. Species As of 2008 there were recognized 34 extant species in the genus ''Biomphalaria'' in total (22 American species and 12 Old World species). There were also described number of fossil ''Biomphalaria'' species. American species include: # '' Biomphalaria amazonica'' Paraense, 1966 # '' Biomphalaria andecola'' (d'Orbigny, 1835) # '' Biomphalaria cousini'' # '' Biomphalaria edisoni'' Es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonadal Dysgenesis
Gonadal dysgenesis is classified as any congenital developmental disorder of the reproductive system in the male or female. It is the atypical development of the gonads in an embryo, with reproductive tissue replaced with functionless, fibrous tissue, termed streak gonads. Streak gonads are a form of aplasia, resulting in hormonal failure that manifests as sexual infantism and infertility, with no initiation of puberty and secondary sex characteristics. Gonadal development is a genetically controlled process by the chromosomal sex ( XX or XY) which directs the formation of the gonad (ovary or testis). Differentiation of the gonads requires a tightly regulated cascade of genetic, molecular and morphogenic events. At the formation of the developed gonad, steroid production influences local and distant receptors for continued morphological and biochemical changes. This results in the appropriate phenotype corresponding to the karyotype (46,XX for females and 46,XY for males). Gon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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