Test Practice Genetics and Heredity

Test Practice Genetics and Heredity

Punnett Square

50% Yellow - 50% Green (Phenotype)

2/4 Yellow - 2/4 Green [ 2/4 = 1/2 ]

Yy - Heterozygous ( Genotype )

yy - Homozygous ( Genotype )

Yy - Dominant

yy - Recessive

Punnett Square

GENOTYPE :

aa(male) - recessive homozygous

AA (female)- Dominant homozygous

Aa(offspring): heterozygous - dominant

PHENOTYPE: 100% black

Multiple Choice

Use this Punnett square to answer the question.

In horses, the gene for white hair (W) is dominant to the gene for non-white hair (w). A horse with genotype (WW) was crossed with a horse with genotype (ww), as shown in the Punnett square.

What fraction of the offspring should be expected to have white hair?

• none

• one-half

• three-quarters

• all

Punnett Square

aa - recessive homozygous

Aa - Dominant heterozygous

Offspring:

- 1/2 black heterozygous - dominant

- 1/2 white homozygous - recessive

Multiple Choice

In a certain species of meadow mouse, dark coat color is dominant over cream coat color. If heterozygous dark-coated male mice are mated with cream-coated female mice, what would be the expected percentage of phenotypes in their offspring?

• 25% dark coated, 75% cream coated

• 50% dark coated, 50% cream coated

• 75% dark coated, 25% cream coated

• 100% dark coated

Multiple Choice

In pea plants, the gene for tallness (T) is dominant over the gene for shortness (t). If 100% of the F1 generation offspring are heterozygous tall, what were the most probable genotypes of the parent plants?

• Tt x Tt

• Tt x tt

• TT x Tt

• TT x tt

Multiple Choice

When a mouse with black fur is crossed with a mouse with white fur, all F1 generation offspring have grey fur. Which phenotypic results can be expected in the F2 generation?

• 100% grey

• 25% black, 75% white

• 50% black, 50% white

• 25% black, 50% grey, 25% white

Multiple Choice

Which statement about DNA is correct?

• A child's DNA will be unrelated to the mother's or father's DNA.

• A child's DNA will show similarities to both the mother's and father's DNA.

• A female child's DNA will exactly match the mother's DNA.

• A male child's DNA will exactly match the father's DNA.