Look up: Sex-Chromosomes

1. 
   sex chromosomes
   (Variation and inheritance) the pair of chromosomes that determine sex. Females have XX chromosomes and males have XY.
   Found on http://www.bbc.co.uk/schools/gcsebitesiz
   
   
2. 
   Sex chromosomes
   the X and Y chromosomes that determine a person's gender; women normally have two X chromosomes and men normally have one X and one Y
   Found on http://www.medichecks.com/glossary.cfm?l
   
   
3. 
   sex chromosomes
   The homologous chromosomes that are dissimilar in the heterogametic sex. There are the x chromosome, the y chromosome, and the w, z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth bombyx mori, for example). In such cases the w chromosome is the female-determining and the male is zz. ... (12 Dec 1998) ...
   Found on http://www.mondofacto.com/facts/dictiona
   
   
4. 
   sex chromosomes
   the chromosomes responsible for determination of the sex of the individual that develops from a zygote; in mammals they are an unequal pair, the X and Y chromosomes.
   Found on http://www.mercksource.com/pp/us/cns/cns
   
   
5. 
   sex chromosomes
   the pair of chromosomes responsible for sex determination. In humans and most animals, the sex chromosomes are designated X and Y; females have two X chromosomes, males have one X and one Y chromosome In certain birds, insects, and fishes the sex chromosomes are designated Z and W; males have two Z chromosomes, females may have one Z and one W chro...
   Found on
   
   
6. 
   sex chromosomes
   The X and Y chromosomes in human beings that determine the sex of an individual. Females have two X chromosomes in diploid cells; males have an X and a Y chromosome. The sex chromosomes comprise the 23rd chromosome pair in a karyotype. Compare autosome.
   Found on http://linkage.rockefeller.edu/wli/gloss
   
   
7. 
   Sex-Chromosomes
   The chromosomes that determine whether an animal will be male or female are known as the Sex Chromosomes or the X and Y Chromosomes. Females have a XX Genotype, while males have a XY Genotype. The female X chromosome contains more genetic material than the male Y chromosome, unlike the other chromosome pairs. (All other chromosomes are known as Autosomes.)
   Found on http://www.mhref.com/color/genetics/glos