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Found X chromosome 20 times.

Displaying results 1 to 10.

1. Autosome
A chromosome not involved in sex determination. The diploid human genome consists of 46 chromosomes, 22 pairs of autosome s, and 1 pair of sex chromosome s (the X and Y chromosomes).

2. Autosomes
The chromosomes other than the sex chromosomes . Each member of an autosome pair (in diploid organisms) is of similar length and in the genes it carries.

3. Bobbed
The name for a variety of Drosophila (a fruit fly) mutation where the bristles (mostly on the back of the head) are very short and thin compared to normal fruit fly bristles. Also, the number of copies of gene s encoding rRNA molecules are reduced.The mutant allele is located on the sex chromosome s and is recessive .

4. Fragile X syndrome
Fragile X syndrome is characterized by mental retardation, autistic-like behavior and other physical abnormalities. Though it is usually most severe/more common in males (they are more susceptible because they have only one X chromosome whereas females have two), both males and females can be affected and their karyotype shows a gap (the fragile site) on the long arm of the X chromosome.

5. Haldane's rule (Haldane's law)
If one of the two sexes is missing, sterile, or rare in a population of first-generation hybrid s between two different species , then that sex is the heterogametic sex (has two different sex chromosome s, such as XY as opposed to XX).

6. Hemizygous gene
Any gene which is present as only one copy in a diploid genome , when most other genes in the genome are present as two copies. The genes on the sex chromosome s of members of the heterogametic sex of a species are all hemizygous genes (for example, in humans, males have hemizygous genes on their X and Y chromosome s because they do not have two copies of either of those chromosomes).

7. Hemizygous
Having one or more genes that have no allele counterparts. Usually applied to genes on the male's X chromosome (in humans).

8. 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 .

9. Homogametic sex
The gender which has two copies of the same sex chromosome . For example: In humans, the female is homogametic because she is XX (has two copies of the X chromosome ). In birds, the male is homogametic because he is ZZ (has two copies of the Z chromosome ). Compare heterogametic sex .

10. 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 .

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