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  2. Y chromosome - Wikipedia

    en.wikipedia.org/wiki/Y_chromosome

    Males have one Y chromosome and one X chromosome, while females have two X chromosomes. In mammals, the Y chromosome contains a gene, SRY, which triggers embryonic development as a male. The Y chromosomes of humans and other mammals also contain other genes needed for normal sperm production. [citation needed] There are exceptions, however.

  3. Sex-determination system - Wikipedia

    en.wikipedia.org/wiki/Sex-determination_system

    Sex-determination system. Some chromosomal sex determination systems in animals. A sex-determination system is a biological system that determines the development of sexual characteristics in an organism. [1] Most organisms that create their offspring using sexual reproduction have two common sexes and a few less common intersex variations.

  4. XY sex-determination system - Wikipedia

    en.wikipedia.org/wiki/XY_sex-determination_system

    The XY sex-determination system is a sex-determination system present in many mammals, including humans, some insects (Drosophila), some snakes, some fish (guppies), and some plants (Ginkgo tree). In this system, the sex of an individual usually is determined by a pair of sex chromosomes. Typically, females have two of the same kind of sex ...

  5. Sexual differentiation in humans - Wikipedia

    en.wikipedia.org/wiki/Sexual_differentiation_in...

    The human Y chromosome showing the SRY gene which codes for a protein regulating sexual differentiation. Sexual differentiation in humans is the process of development of sex differences in humans. It is defined as the development of phenotypic structures consequent to the action of hormones produced following gonadal determination. [1]

  6. Sex chromosome - Wikipedia

    en.wikipedia.org/wiki/Sex_chromosome

    Sex chromosomes (also referred to as allosomes, heterotypical chromosome, gonosomes, heterochromosomes, [1][2] or idiochromosomes[1]) are chromosomes that carry the genes that determine the sex of an individual. The human sex chromosomes are a typical pair of mammal allosomes. They differ from autosomes in form, size, and behavior.

  7. Mitochondrial Eve - Wikipedia

    en.wikipedia.org/wiki/Mitochondrial_Eve

    None. In human genetics, the Mitochondrial Eve (more technically known as the Mitochondrial-Most Recent Common Ancestor, shortened to mt-Eve or mt-MRCA) is the matrilineal most recent common ancestor (MRCA) of all living humans. In other words, she is defined as the most recent woman from whom all living humans descend in an unbroken line ...

  8. XY gonadal dysgenesis - Wikipedia

    en.wikipedia.org/wiki/XY_gonadal_dysgenesis

    XY complete gonadal dysgenesis, also known as Swyer syndrome, is a type of defect hypogonadism in a person whose karyotype is 46,XY. Though they typically have normal vulvas, [1] the person has underdeveloped gonads, fibrous tissue termed "streak gonads", and if left untreated, will not experience puberty. The cause is a lack or inactivation of ...

  9. Sex verification in sports - Wikipedia

    en.wikipedia.org/wiki/Sex_verification_in_sports

    Sex verification in sports (also known as gender verification, or as gender determination or a sex test) occurs because eligibility of athletes to compete is restricted whenever sporting events are limited to a single sex, which is generally the case, as well as when events are limited to mixed-sex teams of defined composition (e.g., most pairs ...