When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Klinefelter syndrome - Wikipedia

    en.wikipedia.org/wiki/Klinefelter_syndrome

    The relevant nondisjunction in meiosis I occurs when homologous chromosomes, in this case the X and Y or two X sex chromosomes, fail to separate, producing a sperm with an X and a Y chromosome or an egg with two X chromosomes. Fertilizing a normal (X) egg with this sperm produces an XXY or Klinefelter offspring.

  3. 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).

  4. Sex differences in human physiology - Wikipedia

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

    Of these 23 pairs of chromosomes, 22 are autosomes, and one is a sex chromosome. [1] There are two kinds of sex chromosomes–X and Y. In humans and in almost all other mammals, females carry two X chromosomes, designated XX, and males carry one X and one Y, designated XY. [1] A human egg contains only one set of chromosomes (23) and is a ...

  5. XY sex-determination system - Wikipedia

    en.wikipedia.org/wiki/XY_sex-determination_system

    Offspring have two sex chromosomes: an offspring with two X chromosomes (XX) will develop female characteristics, and an offspring with an X and a Y chromosome (XY) will develop male characteristics, except in various exceptions such as individuals with Swyer syndrome, that have XY chromosomes and a female phenotype, and de la Chapelle Syndrome ...

  6. Sex-determination system - Wikipedia

    en.wikipedia.org/wiki/Sex-determination_system

    In this system, females have two of the same kind of sex chromosome (XX), while males have two distinct sex chromosomes (XY). The X and Y sex chromosomes are different in shape and size from each other, unlike the rest of the chromosomes ( autosomes ), and are sometimes called allosomes .

  7. XXYY syndrome - Wikipedia

    en.wikipedia.org/wiki/XXYY_syndrome

    48,XXYY syndrome is a condition related to the X and Y chromosomes (the sex chromosomes). People normally have 46 chromosomes in each cell.Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics.

  8. Disorders of sex development - Wikipedia

    en.wikipedia.org/wiki/Disorders_of_sex_development

    Klinefelter syndrome (47,XXY and XXY syndrome) – a condition that describes a male born with at least one extra X chromosome. Though the most common variation is 47,XXY, a man may also be 48,XXXY or 49,XXXXY. It is a common occurrence, affecting 1 in 500 to 1,000 men. [44]

  9. Sex chromosome - Wikipedia

    en.wikipedia.org/wiki/Sex_chromosome

    The 23rd pair of chromosomes are called allosomes. These consist of two X chromosomes in females, and an X chromosome and a Y chromosome in males. Females therefore have 23 homologous chromosome pairs, while males have 22. The X and Y chromosomes have small regions of homology called pseudoautosomal regions.