Mouse Genetics Gizmo Lesson 1.3 Review

(4) What are the genotypes of the two “Pure” mice in the Mouse Genetics Gizmo?

• Black and White

• ff and Ff

• FF and ff

• Black and Gray

These mice are considered "Pure" because...

• they have never mated before.

• they are both homozygous.

• they are both heterozygous.

• they each only have one color.

Answer explanation

(4) The black mouse would be homozygous dominant.

(4) The white mouse would be homozygous recessive.

(7) What is the genotype of the offspring mice?

• Ff

• FF

• ff

• FF and Ff

The offspring mice inherit two different alleles Ff, which makes them all...

• Homozygous Dominant.

• Homozygous recessive.

• Heterozygous.

• Hybrid.

• Purebred.

(8) The offspring in this mating are all black which means

• white fur is the dominant allele.

• black fur is the dominant allele.

• black fur is the recessive allele.

• white fur is the recessive allele.

• the white mouse did not pass an allele to the offspring.

Answer explanation

Since all the offspring have a black phenotype, the more influential, dominant allele must be black. fur color.

The less influential, recessive allele must be white fur color because white fur color is masked or hidden by the dominant black fur color.

(11 a/b) What alleles could each parent in this example pass on?

• f

• F

• Ff

• F or f

(11 c) What are the possible genotypes for the offspring in this mating?

• ff

• Ff

• FF

• Ff

Answer explanation

Each Ff black mouse will pass down either a "F " or a "f" creating the possible genotypes of FF, Ff, Ff, and ff.