Answer :
In a pedigree chart, a symbol used to label a male that expresses a sex-linked disorder is usually a square. In the context of pedigree charts, squares are typically used to represent males, while circles are used to represent females. When a male individual is affected by a sex-linked disorder, such as color blindness or hemophilia, a filled-in square is often used to indicate this condition.
This visual representation helps to identify and track the inheritance pattern of the sex-linked disorder within a family tree. By looking at the pedigree chart, one can see how the disorder is passed down from generation to generation and determine its prevalence among male family members.
Therefore, when analyzing a pedigree chart to identify a male individual expressing a sex-linked disorder, look for a filled-in square symbol within the chart, which indicates that the male is affected by the specific sex-linked condition being studied.
