Each parent contributes one of two genes for a particular trait. The gene pairs are called
a. variables. 
b. hybrids.

c. alleles. 

d. gametes.

c. alleles. 

Mendel’s principle of segregation refers to the
a. separation of alleles for a particular trait during gamete formation.
b. independent behavior of alleles for different traits during gamete formation.
c. difference of alleles for a trait in a heterozygous genotype.
d. expression of phenotype in an individual.

a. separation of alleles for a particular trait during gamete formation.

When an individual heterozygous for a trait is crossed with an individual homozygous recessive for the trait, the offspring produced will
a. all have the same genotype.
b. show two different phenotypes.
c. show three different phenotypes.
d. all have the same phenotype.

a. all have the same genotype. 

In rabbits, black fur (B) is dominant to brown fur (b). Consider the following cross between two rabbits.

Refer to the illustration above. The genotypic ratio of the F1 generation would be
a. 1:1. 
b. 3:1.

c. 1:3. 

d. 1:2:1.

d. 1:2:1.

In humans, having freckles (F) is dominant to not having freckles (f). The inheritance of these traits can be studied using a Punnett square similar to the one shown below.

Refer to the illustration above. The child represented in box 1 in the Punnett square would
a. be homozygous for freckles.
b. have an extra freckles chromosome.
c. be heterozygous for freckles.
d. not have freckles.

a. be homozygous for freckles. 

The Pace family has seven children, one son and six daughters. What is the chance that the eighth child will be a daughter?
a. 1/12 
b. 1/128

c. 1/8 

d. 1/2

d. 1/2

If homozygous red-flowered plants crossed with white-flowered plants produced all red- flowered offspring (F1 generation), the gene for red flowers must have been
a. recessive. 
b. dominant.

c. a multiple allele. 

d. homozygous in the offspring.

b. dominant.

Tallness (T) is dominant to shortness (t) in pea plants. Which of the following represents a genotype of a pea plant that is heterozygous for tallness?
a. T 
b. TT

c. Tt 

d. tt

c. Tt 

Which of the following traits is controlled by multiple alleles in humans?
a. eye color  
b. blood type

c. colorblindness

d. albinism

b. blood type

In humans, having freckles (F) is dominant to not having freckles (f). The inheritance of these traits can be studied using a Punnett square similar to the one shown below.

Refer to the illustration above. The parents shown in the Punnett square could have children with a phenotype ratio of
a. 1:2:1.  
b. 4:0.

c. 3:1.

d. 2:2.

c. 3:1.

Mendel discovered principles of inheritance because he
a. observed simultaneously all of the characteristics in which parents differed.
b. believed that hereditary characteristics of two individuals blended in the offspring.
c. ignored all characteristics except a few markedly contrasting ones that he studied carefully.
d. studied only the offspring obtained from a single mating.

c. ignored all characteristics except a few markedly contrasting ones that he studied carefully. 

If two offspring result from the cross Aa ´ Aa, what is the probability that both offspring will have the genotype aa?
a. 1/16 
b. 1/8

c. 1/4 

d. 1/2

a. 1/16 

In rabbits, black fur (B) is dominant to brown fur (b). Consider the following cross between two rabbits.

Refer to the illustration above. The device shown, which is used to determine the probable outcome of genetic crosses, is called a
a. Mendelian box. 
b. Punnett square.

c. genetic graph. 

d. phenotypic paradox.

b. Punnett square.

When Mendel crossed true-breeding tall plants with true-breeding short plants, all the offspring were tall because
a. the allele for tall plants is recessive.
b. the allele for short plants is dominant.
c. the allele for tall plants is dominant.
d. they were true-breeding like their parents.

c. the allele for tall plants is dominant.

In humans, having freckles (F) is dominant to not having freckles (f). The inheritance of these traits can be studied using a Punnett square similar to the one shown below.

Refer to the illustration above. Which box in the Punnett square represents a child who does not have freckles?
a. box 1 
b. box 2

c. box 3 

d. box 4

d. box 4

In mating pea plants with wrinkled seeds and pea plants with round seeds, Mendel found the F1 offspring produced only green pods. Mendel suggested that the yellow trait
a. skips every other generation.
b. blends with the round to produce a slightly wrinkled green pod.
c. permanently disappears from the breeding line.
d. is not expressed when its factor is present in combination with the round factor.

d. is not expressed when its factor is present in combination with the round factor.

An allele that is always expressed whenever it is present is called
a. dominant. 
b. phenotypic.

c. recessive. 

d. superior.

a. dominant. 

In rabbits, black fur (B) is dominant to brown fur (b). Consider the following cross between two rabbits.

Refer to the illustration above. Both of the parents in the cross are
a. black. 
b. brown.

c. homozygous dominant. 

d. homozygous recessive.

a. black.

A cross of a white hen with a black rooster produces erminette-color offspring. This type of inheritance is known as
a. incomplete dominance.  
b. polygenic inheritance.

c. codominance.

d. multiple alleles.

c. codominance.

In humans, having freckles (F) is dominant to not having freckles (f). The inheritance of these traits can be studied using a Punnett square similar to the one shown below.

Refer to the illustration above. The child in box 3 of the Punnett square has the genotype
a. FF. 
b. Ff.

c. ff. 

d. FfFf.

b. Ff.

Mendel’s above explanation is best supported by which evidence?
a. A cross of the F1 offspring produced 50% plants with round seeds.
b. Twenty-five percent of the offspring of the F1 cross produced wrinkled seeds.
c. Repeated crosses between plants with wrinkled and round seeds produced only plants with round seeds.
d. When true-breeding plants with wrinkled seeds self-fertilize, they produce only plants with wrinkled seeds.

b. Twenty-five percent of the offspring of the F1 cross produced wrinkled seeds.

The phenotype of an organism
a. is used to represent its genetic composition.
b. is the physical appearance of a trait.
c. occurs only in dominant individuals.
d. cannot be seen.

b. is the physical appearance of a trait.

In rabbits, black fur (B) is dominant to brown fur (b). Consider the following cross between two rabbits.

Refer to the illustration above. The phenotype of the offspring indicated by box 3 would be
a. brown. 
b. black.

c. a mixture of brown and black. 

d. white.

b. black.

Imagine two heterozygous parents. Each has a dominant allele X for brown eyes and a recessive allele x for blue eyes. The phenotypic ratio for brown:blue eyes in their children is
a. 1:2:1.
b. 3:1.
c. 9:3:3:1.
d. 1:3:1.

b. 3:1. 

What type of chart is shown in Figure 7.4?
a. pedigree  
b. punnett square

c. cladogram

d. bar graph

a. pedigree 

Using the figure above, what do the shaded shapes represent?
a. carriers of the trait 
b. individuals with a given phenotype
c. individuals that DO NOT express the trait 

d. heterozygous individuals

b. individuals with a given phenotype