Pedigree and x linked color blindness trait?

A way to explain why a human pedigree of the x linked color-blindness trait is suggestive of an X linked trait?

Pedigree and x linked color blindness trait?
An X-linked trait means that the trait is located on the X chromosome.





Females with have the trait only rarely. Males are much more likely to have color blindness. They only have one X chromosome, so if they receive the recessive allele on their X chromosome, they don't have another dominant allele on another X chromosome to cover the color-blindness allele up. Thus, they will have color-blindness.





Females basically have two chances. They can be normal, either homozygous dominant or heterozygous (carrier), or color-blind (homozygous recessive). They need TWO recessive alleles to have color-blindness, so it is less likely they will have it.





So on a pedigree, if basically everyone that is affected is male, you can tell color-blindess is X linked.