Early-onset Alzheimer’s disease affects people under the age of 65. Less than five percent of people who are diagnosed with Alzh
eimer’s disease have this type. Many cases of early-onset Alzheimer’s disease are inherited, a type known as familial Alzheimer’s disease (FAD). Which statement is best supported by this information? F) FAD is the result of a genetic change in one or more chromosomes.
G) Natural selection will continue to reduce the incidence of FAD.
H) FAD affects only the genes of middle-aged people.
J) Deletion of one amino acid causes FAD.
The genotype Tt is heterozygous, which means it has both the dominant and recessive trait in the genotype. The reason it is tall is because that is the dominant trait, and the dominant trait basically covers up the recessive trait (unless you are talking about incomplete dominance or codominance).
