Final answer:
To determine if sensitivity to poison ivy is inherited as a dominant or recessive trait, one must analyze the pedigree chart for the appearance of the trait in each generation. A dominant trait would not skip generations, whereas a recessive trait might. Without the actual chart, a definitive answer cannot be given.
Step-by-step explanation:
To determine whether sensitivity to poison ivy is a result of a dominant or recessive allele, we can analyze the given pedigree chart. If the trait of sensitivity to poison ivy does not skip generations and appears in every generation, then it is likely a dominant trait. On the contrary, if the trait skips generations or appears in individuals whose parents do not have the trait, it is likely recessive. In Mendelian inheritance, a dominant allele will express the trait even if only one copy is present (heterozygous), where as recessive allele, must be present in two copies (homozygous recessive) to express the trait.
Without the provided pedigree chart, the specific inheritance pattern cannot be conclusively determined, but given the explanation of simple dominance, one could infer the trait as dominant or recessive based on how the trait appears across generations.