_________ is a family tree.

Sure, here is a step-by-step solution for a pedigree problem: **Problem:** In a pedigree chart, a particular trait is observed to be present in every generation. What is the mode of inheritance for this trait? **Solution:** Step 1: Determine if the trait is dominant or recessive by examining the pattern of inheritance. - If the trait is dominant, it should be present in every generation, and at least one parent of an affected individual should also be affected. - If the trait is recessive, it may skip generations, and affected individuals may have unaffected parents. Step 2: Examine the pedigree chart to determine if the trait is autosomal or sex-linked. - Autosomal traits are located on non-sex chromosomes (chromosomes 1-22), and affect both males and females equally. - Sex-linked traits are located on the sex chromosomes (X or Y), and may affect males and females differently. Step 3: Determine the mode of inheritance based on the pattern observed in the pedigree chart. - If the trait is dominant and autosomal, the mode of inheritance is likely autosomal dominant. - If the trait is recessive and autosomal, the mode of inheritance is likely autosomal recessive. - If the trait is dominant and sex-linked, the mode of inheritance is likely X-linked dominant. - If the trait is recessive and sex-linked, the mode of inheritance is likely X-linked recessive. Step 4: Confirm the mode of inheritance with additional testing or genetic analysis, if necessary.