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Found W chromosome 5 times.

Displaying results 1 to 10.

1. Heterogametic sex
The gender which has two different sex chromosome s. For example: In humans, the male is heterogametic because he is XY (has an X chromosome and a Y chromosome ). In birds, the female is heterogametic because she is WZ (has a W chromosome and a Z chromosome ). Compare homogametic sex .

2. Nondisjunction
The failure of chromosomes to separate properly during cell division. The unequal segregation of chromosomes during meiosis . This forms cells with either too many (possibly one or more single or sets of chromosomes too many) or too few chromosomes. Thought to be a common cause for Down Syndrome, where sufferers often have an extra copy of chromosome 21.

3. Sex chromosomes
The chromosome s which determine the gender of the organism (for organisms whose gender is determined by gene s rather than by environment). In humans, fruit flies, and other animals where the male is the heterogametic sex , they are the X chromosome s and Y chromosome s. In birds, moths, and other animals where the female is the heterogametic sex, they are the W chromosome s and Z chromosome s. For humans, the sex chromosomes are the 23rd pair of all chromosomes. The sex chromosomes of most plants (when they exist) are also known as X and Y chromosomes; Ginkgo trees have a different system of sex chromosomes. Compare autosome .

4. W chromosome
A sex chromosome found in all birds and certain other animals where the female is the heterogametic sex . The W chromosome causes the individual to become female in bird species. It is part of the WZ set of sex chromosomes, where the female has one W chromosome and one Z chromosome , and the male has two Z chromosomes.

5. Z chromosome
A sex chromosome found in all birds and certain other animals where the female is the heterogametic sex . It is part of the WZ set of sex chromosomes, which are so designated to prevent confusion with the XY set of sex chromosomes for species where the male is the heterogametic sex. In the WZ system, the male has two Z chromosomes and the female has only one (and one W chromosome ).

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