Answer: (below)
Explanation:
Question 4:
When you look at a pedigree, a circle means a female, and a square means a male. If the shape is filled in, that means the individual has the trait that is being studied. If the shape is filled in halfway, that means the individual is a carrier for the trait, meaning that they have one allele for it, but the trait is not present in their phenotype. If the shape is not filled in at all, that means the individual doesn't have the allele for the trait at all, so the trait is not present in their phenotype as well.
Now, for this question, fully shaded shapes represent the individuals who have sickle cell anemia. Therefore, looking at the chart, we can conclude that individual 2 in the parental generation and individual 3 in F2 (second generation) have sickle cell anemia.
Question 5:
When a disease is dominant, it tends to show up in every generation of the pedigree chart. This is because you only need one of the dominant allele to have the trait expressed.
When a disease is recessive, it tends to skip generations in the pedigree chart. This is because you need both recessive alleles to have the trait expressed. Therefore, the trait can "hide" in carriers.
Looking at the chart, it seems like a generation is skipped. Sickle cell anemia is present in an individual of the parental generation, but the next time it reappears, it's present in an individual of the second generation. Therefore, we can conclude that sickle cell anemia is recessive.
