What are sex-linked traits?

Sex-linked traits are defined as characteristics that are associated with genes located on the sex chromosomes, which in many species, including humans, are the X and Y chromosomes. The significance of this relationship lies in how traits are inherited differently based on the sex of the individual. For example, males (XY) and females (XX) have different patterns of inheritance for these traits.

In the case of X-linked traits, a mutation or gene expression on the X chromosome can lead to a trait being expressed more prominently in males, as they have only one X chromosome. This means that if a male inherits an X-linked recessive trait, it will be expressed because there is no corresponding allele on the Y chromosome to mask it. Conversely, females, having two X chromosomes, may be carriers of the trait and exhibit different expressions based on the alleles present on both X chromosomes.

This context illustrates why options relating to autosomes, environmental factors, or dominance do not accurately describe sex-linked traits.