Punnett Squares (PL)

This Punnett square shows the crossing of two heterozygous plants with red flowers. R = dominant red, r = recessive white

e

d

c

b

a

Recessive allele

Heterozygous red

Dominant allele

Homozygous white

Homozygous red

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In this Punnett square you can see the possible genes for fur color of mice. B is the gene for black and b is the gene for white. If you are black, the pair of genes you possess must be BB or Bb. If your fur is white you have the combination bb.

Groups:

(a) Fraction that should be black

,

(b) Percent that will be white

,

(c) Probability that a mouse will be white

,

(d) Ratio of black to white mice

• 3/4

• 25

• 3:1

• 1:4

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

Match the following

• allele

• The physical expression of genes.

• Phenotype

• This is an organism or cell with two sets of chromosomes.

• Diploid

• This is an observable trait of an organism that can mask the recessive trait.

• Dominant trait

• This is an alternative form of a gene.

• Trait

• A specific characteristic that varies from one individual to another.

Match the following

• Genotype

• A trait that can be masked by another one.

• Recessive trait

• This is a segment of DNA on the chromosome that is coded for a particular trait.

• Gene

• The genetic makeup of an organism.

Consider the possible genotypes of the offspring of two heterozygous brown goats. The ratio of brown to white offspring in this case would be

• 1:3

• 2:2

• 3:1

• 3:4

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In pole beans, green pods (G) are a dominant trait, while yellow pods (g) are a recessive trait. A bean plant with a GG genotype is crossed with a second plant that has the gg genotype. If this cross produces 500 offspring, approximately how many of the offspring will have green pods?

• 0

• 125

• 250

• 
  500

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

According to the Punnett square: B represents the dominant gene for blue feathers and b represents the recessive gene for red feathers. Two heterozygous birds have one offspring. What percent chance does it have for red feathers?

• 0%

• 25%

• 75%

• 100%

The white-tailed deer, Odocoileus virginianus, is common in the Eastern United States. Most deer have reddish brown fur, but occasionally a deer may be born with a genetic condition known as albinism which results in white fur. Albinism is caused by the inheritance of two recessive alleles for the production of coloration pigments.

If an albino deer is born to two parents who each have normal fur coloration, what conclusion may be drawn about the genotypes of the parent deer?

• Both parents must be homozygous for the coloration gene.

• Both parents must be heterozygous for the coloration gene.

• The female parent must have two recessive alleles for the coloration gene.

• No conclusion may be drawn about the parental genotypes based on the information given.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Do you forget things? Absent-mindedness is an inherited recessive trait. The Punnett square shows the genetic cross for absent-mindedness in the Smith family. If the Smith's have six children, how many could be absent-minded?

• 0

• 1

• 2

• 3

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

Some fruit flies are born with curly wings which makes them unable to fly. It has been shown that curly wings are caused by a dominant gene which can be represented by the symbol W, while the recessive normal wing gene is represented by the symbol w. If a parent fly with the genotype WW is crossed with a parent of the genotype Ww, what percentage the offspring will have curly wings?

• 100%

• 75%

• 50%

• 25%

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3