X chromosome

chromosome which determines the gender of a fetus

The X chromosome is one of the two sex-determining chromosomes in many animal species, including mammals (the other is the Y chromosome). It is a part of the XY sex-determination system and X0 sex-determination system. The X chromosome was named for its unique properties by early researchers, and this resulted in its counterpart being named the Y chromosome for the next letter in the alphabet when it was discovered later .
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Noun
1. the sex chromosome that is present in both sexes: singly in males and doubly in females; "human females normally have two X chromosomes"
(hypernym) sex chromosome

The sex chromosome found twice in normal females and singly, along with a Y chromosome, in normal males.

CROMOSOMA X

CROMOSOMA X