EOC Human Genetics

In human genetics, brown eyes (B) are dominant over blue eyes (b). A brown-eyed man is heterogeneous (Bb). He marries a blue-eyed woman. What is the probability of their child having blue eyes?

• 100%

• 75%

• 50%

• 25%

Answer explanation

The probability of their child having blue eyes is 50% because the man is heterozygous (Bb) and can pass on the recessive blue eye gene to the child.

Tags

NGSS.HS-LS3-3

Which of the following is a phenotype?

• Aa

• red hair

• heterozygous

• DNA

Answer explanation

The correct choice is 'red hair' because it is a visible trait or characteristic resulting from the interaction of an organism's genotype with the environment.

Which genotype is NOT possible in the offspring produced by the cross?

• AaGG

• Aagg

• aaGg

• aaGG

Answer explanation

The genotype 'Aagg' is not possible in the offspring because it requires both parents to contribute a lowercase 'a' allele, which is not present in the parent genotype AaGG.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In sheep, producing white wool (W) is dominant to black wool (w), and having brown eyes (E) is dominant to blue eyes (e). A cross of two heterozygous sheep is shown in the Punnett square below
Which of the following describes an outcome of this cross?

• 1/16 will have white wool and brown eyes

• 3/16 will have black wool and brown eyes

• 4/16 will have white wool and blue eyes

• 9/16 will have black wool and blue eyes

Answer explanation

The correct choice is 3/16 will have black wool and brown eyes because the Punnett square shows the possible genotypes and phenotypes resulting from the cross of two heterozygous sheep.

Tags

NGSS.HS-LS3-1

When red carnations are crossed with white carnations, the resulting flowers are pink. Pink carnations are an example of what type of inheritance pattern?

• incomplete dominance

• recessive alleles

• dominant alleles

• codominance

Answer explanation

The correct inheritance pattern is incomplete dominance, where the heterozygous genotype results in an intermediate phenotype, in this case, pink carnations.

Which explanation describes how the presence of a white flower color occurred in the offspring?

• Parents are homozygous for the dominant gene expressing red color.

• Parents are heterozygous for the dominant gene expressing red color.

• Parents are homozygous for the recessive gene expressing white color.

• Parents are heterozygous for the recessive gene expressing white color.

Answer explanation

The presence of a white flower color occurred in the offspring because the parents are heterozygous for the recessive gene expressing white color.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Some angelfish colors are determined by codominance. Possible phenotypes and genotypes of angelfish colors are shown.

Which table shows the expected phenotypes of offspring resulting from a cross between a black angelfish and a black-lace angelfish?

• 
• 
• 
• 

Tags

B.6(F)

Which best explains why children resemble their parents?

• They eat the same foods.

• They have similar DNA.

• They speak the same language

• They have the same interests.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

A litter of kittens have traits that are similar to both the mother cat and the father cat. Which best explains this situation?

• The kittens are provided the same kind of milk from their mother as they
  grow.

• The kittens inherit some of their traits from their mother and some from their father.

• The kittens are kept at the same temperatures by their mother when they are first born.

• The kittens are taught by their parents to have similar traits.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Which are examples of inherited traits?

• specific beliefs

• fingerprints

• memories

• nose shape

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2