Genetics Unit Test

A scientist is studying fruit fly wings. Straight wings are dominant, and curly wings are recessive. Which statement correctly describes the F₁ generation if a straight-winged parent is crossed with a curly-winged parent and if both parents are true breeding?

• The offspring will have two genes for straight wings.

• The offspring will produce only gametes that have genes for curly wings.

• The offspring will have one allele for straight wings and one allele for curly wings.

• The offspring will have only one kind of allele for the gene that determines wing type.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

A pea plant exhibits a recessive trait. Which statement is most likely true about the plant?

• The plant is identical to its parent plant.

• The plant has different alleles for the gene that codes for the trait.

• The plant has two identical alleles for the gene that codes for the trait.

• The plant does not have the same genes for the trait as its parent plant.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In the F₂ generation of Mendel’s crosses,

• all plants had the dominant trait.

• half of the plants had the dominant allele.

• all plants had both the dominant and recessive alleles.

• one in four plants had two alleles for the recessive trait.

Tags

NGSS.HS-LS3-3

Red-green color blindness is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree.

Which individuals in the pedigree are identified and labeled carriers for red-green color blindness?

• Lisa and Monica

• Sam, Tim, Bella, and Joshua

• Ben, Jenny, Mike, Carol, Katie, and Chris

• Ben and Lisa

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. A pansy that is homozygous for purple flowers (PP) is crossed with a pansy that is homozygous for pink flowers (pp). Which genotypes will be included for the offspring in the Punnett square for this cross?

• PP, Pp, and pp

• PP and pp

• PP and Pp

• Pp only

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. A parakeet that is heterozygous for blue feathers (dominant) is crossed with a parakeet that is homozygous for white feathers (recessive). According to the Punnett square for this cross, what percentage of offspring is predicted to have blue feathers?

• 25 percent

• 50 percent

• 75 percent

• 100 percent

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Unattached earlobes is a dominant trait, E. A parent who is homozygous for unattached earlobes is crossed with a parent who is homozygous for attached earlobes. Which describes the genotypes of their offspring?

• 100 percent Ee

• 100 percent unattached earlobes

• 100 percent ee

• 100 percent attached earlobes

Tags

NGSS.HS-LS3-1

In the F₁ generation of a Mendelian cross,

• only the dominant trait is visible.

• only the recessive trait is visible.

• neither the dominant nor recessive trait is visible.

• both the dominant and recessive traits are visible.

If a scientist wanted to follow Mendel’s experiment with a different kind of plant, which type of plant would she examine?

• A plant that cannot self-pollinate.

• A plant that has only recessive alleles.

• A plant that has three alleles for a trait.

• A plant that has only two alleles for a trait.

Tags

NGSS.HS-LS3-2

Which allele combination represents a male who has an X-linked recessive disorder?

• X^rY

• X^RY

• X^rX^r

• X^RX^r