Final answer:
A female carrier of an X-linked recessive disorder will have sons with a 50 percent chance of being affected by the disorder, as males receive one X chromosome from the mother and have no second X chromosome to offset a recessive mutated gene.
Step-by-step explanation:
When considering an X-linked recessive disorder, if a female who is a carrier (meaning she has one copy of the mutated gene on one of her X chromosomes) mates with a male who does not have the disorder (he has normal X and Y chromosomes), their sons will have a 50 percent chance of being affected by the disease. This is because sons receive one X chromosome from their mother and one Y chromosome from their father. Since the mother has one normal X and one X with the recessive disorder, there is a 50 percent probability that she will pass on the X chromosome with the disorder, leading to the son being affected.
Females can be carriers of X-linked recessive diseases and have a normal phenotype because they have two X chromosomes, so even if one is mutated, the other can have the normal gene. However, males either have the disease or are phenotypically normal; they cannot be carriers because they have a single X chromosome. Diseases that follow this pattern include color blindness, hemophilia, and some forms of muscular dystrophy.