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  2. XY sex-determination system - Wikipedia

    en.wikipedia.org/wiki/XY_sex-determination_system

    In the XY sex-determination system, the female-provided ovum contributes an X chromosome and the male-provided sperm contributes either an X chromosome or a Y chromosome, resulting in female (XX) or male (XY) offspring, respectively. Hormone levels in the male parent affect the sex ratio of sperm in humans. [25]

  3. Cytogenetic notation - Wikipedia

    en.wikipedia.org/wiki/Cytogenetic_notation

    Symbol Description , Separates modal number (total number of chromosomes), sex chromosomes, and chromosome abnormalities -Loss of a chromosome ( ) Grouping for breakpoints and structurally altered chromosomes + Gain of a chromosome ; Separates rearranged chromosomes and breakpoints involving more than one chromosome / Separates cell lines or ...

  4. Female - Wikipedia

    en.wikipedia.org/wiki/Female

    The symbol of the Roman goddess Venus is used to represent the female sex in biology. [1] An organism's sex is female (symbol: ♀) if it produces the ovum (egg cell), the type of gamete (sex cell) that fuses with the male gamete (sperm cell) during sexual reproduction. [2] [3] [4] A female has larger gametes than a male.

  5. Sex-determination system - Wikipedia

    en.wikipedia.org/wiki/Sex-determination_system

    No genes are shared between the avian ZW and mammal XY chromosomes [26] and the chicken Z chromosome is similar to the human autosomal chromosome 9, rather than X or Y. This suggests not that the ZW and XY sex-determination systems share an origin but that the sex chromosomes are derived from autosomal chromosomes of the common ancestor of ...

  6. Male - Wikipedia

    en.wikipedia.org/wiki/Male

    The symbol of the Roman god Mars (god of war) is often used to represent the male sex. It also stands for the planet Mars and is the alchemical symbol for iron.. Male (symbol: ♂) is the sex of an organism that produces the gamete (sex cell) known as sperm, which fuses with the larger female gamete, [1] [2] [3] or ovum, in the process of fertilisation.

  7. Sexual differentiation in humans - Wikipedia

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

    In the absence of a Y chromosome, the fetus will undergo female development. This is because of the presence of the sex-determining region of the Y chromosome, also known as the SRY gene. [5] Thus, male mammals typically have an X and a Y chromosome (XY), while female mammals typically have two X chromosomes (XX).

  8. 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.

  9. Sex differences in human physiology - Wikipedia

    en.wikipedia.org/wiki/Sex_differences_in_human...

    The sex chromosome in a human egg is always an X chromosome since a female only has X sex chromosomes. In sperm, about half the sperm have an X chromosome and half have a Y chromosome. [2] If an egg fuses with sperm with a Y chromosome, the resulting individual is male.