Individuals with neurofibromatosis may have a range of phenotypes,from pigment spots on the skin to tumorlike growths.This is an example of

Familial hypercholesterolemia is a genetic disease that affects approximately one in 500 people worldwide.There is more than one genetic cause of the disease.Class I is often described as an autosomal dominant disease.Affected individuals have cholesterol levels >250 as children and often >300 as adults.However,homozygotes have cholesterol levels of >600 as children and can die of heart attacks in their 20s.These individuals entirely lack a functional LDL receptor.Which of the following would be the best description of the inheritance of this form of hypercholesterolemia?

Two true-breeding mutant strains of Drosophila have black body color instead of the wild-type gray yellow.When the two strains are crossed,all the F₁ flies have wild-type body color.How can these data be interpreted?