Chapter 9 Quiz 3

A person with AB blood illustrates the principle of 

• polygenic inheritance
• pleiotropy
• incomplete dominance
• codominance

You decide to mate a finch that is homozygous for an orange beak with a finch that is homozygous for an ivory beak. All offspring have a pale, ivory-orange beak. This is an example of

• codominance
• incomplete dominance
• polygenic inheritance
• pleiotropy

All the offspring of a cross between a red-flowered plant and a white-flowered plant have pink flowers. This means that the allele for red flowers is ________ to the allele for white flowers?

• dominant
• recessive
• codominant
• incompletely dominant

Which of the following is an example of incomplete dominance in humans?

• ABO blood groups 
• skin color
• sickle-cell disease
• hypercholesterolemia

Which term refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes?

• codominance
• pleiotropy
• polygenic inheritence
• incomplete dominance

Which term is essentially the opposite of pleiotropy?

• multiple alleles 
• polygenic inheritance
• incomplete dominance
• codominance

The expression of both alleles for a trait in a heterozygous individual illustrates 

• codominance
• incomplete dominance
• polygenic inheritance
• pleiotropy

In snapdragons, heterozygotes for one of the genes have pink flowers, whereas homozygotes have red or white flowers. When plants with red flowers are crossed with white flowers, what proportion of the offspring will have pink flowers

• 0%
• 25%
• 50%
• 100%

Which of the following terms best describes when the phenotype of the heterozygote differs from the phenotypes of both heterozygotes?

• epistasis
• multiple alleles
• pleiotropy
• incomplete dominance

Cystic fibrosis affects the lungs, the pancreas, the digestive system, and other organs, resulting in symptoms ranging from breathing difficulties to recurrent infections. Which of the following terms best describes this?

• incomplete dominance
• epistasis
• multiple alleles
• pleiotropy