Mendelian and Non-mendelian Genetics Practice Problems

In pea plants, the trait for tall stems is dominant over the trait for short stems. If two heterozygous tall plants are crossed, what percentage of the offspring would be expected to have the same phenotype as the parents?

• 100%
• 75%
• 50%
• 25%

Tags

NGSS.HS-LS3-3

One of the parents of a child has phenylketonuria (PKU), which is caused by recessive alleles. The other parent does not have the PKU alleles. What is the chance that the couple will have a child with phenylketonuria?

• 0%
• 50%
• 75%
• 100%

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Each parent contributes one of the genes for a particular trait. The genes of the pair are called:

• variables
• gametes
• hybrids
• alleles

Tags

NGSS.HS-LS3-1

In snapdragons, Tallness (T) is dominant to dwarfness (t). In a cross between two plants that are heterozygous for this trait, the percent of offspring expected to exhibit dwarfness is

•  25%
• 100%
• 50%
• 0%

Tags

NGSS.HS-LS3-3

In dragons, large scales (S) are dominant and small scales (s) are recessive. A dragon that is heterozygous for the trait is crossed with a dragon that has small scales. What should be the ratio of large-scaled dragons to small-scaled dragons among the offspring?

• 1:2
• 1:1
• 2:1
• 3:1

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

Cystic Fibrosis (CF) is a genetic disorder that is controlled by a recessive allele. If a person suffering from CF were to marry an individual who is heterozygous for the trait, what % of their children could be expected to unaffected carriers of the trait? Ignore issues of sterility in persons with CF.

• 0%
• 25%
• 75%
• 50%

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In pea plants, the allele for green pods (G) is dominant and the allele for yellow pods (g) is recessive. A researcher crosses two green pea plants, and the in F₁ generation, all of the offspring exhibit green pods. Can you determine the genotypes of both parents

• No, they could be Gg and GG OR GG and GG
• Yes, they are Gg and GG
• Yes, they are GG and GG
•  No, they could be Gg and Gg OR GG and Gg

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

A female guinea pig homozygous dominant for black fur color is mated with a male homozygous for white fur color. In a litter of eight offspring, probability would predict there would be _____.

• 8 black guinea pigs  
• 4 black and 4 white guinea pigs  
• 2 black, 4 gray, and 2 white guinea pigs  
• 8 white guinea pigs

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

A red flowered plant (RR) is crossed with a white flowered plant (WW). The gene for petal color in these plants expresses incomplete dominance.  What percentage of the offspring will have pink (RW) flowers?

• 0%
• 25%
• 50%
• 100%

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-3

A calico cat shows both the traits for orange fur and black fur. What kind of allele expression is this?

• Incomplete Dominance
• Co dominance

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2