Name________________________________________________
Heredity Unit Review
MULTIPLE CHOICE. Choose the answer that best completes the statement or answers the question. (40 points)
1) Mendel conducted his most memorable experiments
on (C.1.g)
A) guinea pigs. B) fruit flies.
C) roses.
D) peas.
E) clones.
2) Varieties of plants in which self-fertilization produces
offspring that are identical to the parents are referred to
as (C.1.l)
A) the F2 generation.
B) independent crosses.
C) hybrids.
D) true-breeding.
E) monohybrid crosses.
3) All the offspring of a cross between a black-eyed
mendelien and an orange-eyed mendelien have black
eyes. This means that the allele for black eyes is ________
the allele for orange eyes. (C.1.i)
A) more aggressive than
B) dominant to
C) recessive to
D) codominant to
E) better than
4) The alleles of a gene are found at
_________chromosomes. (C.1.i)
A) the same locus on heterologous
B) the same locus on homologous
C) different loci on heterologous
D) different loci on homologous
E) the same locus on homologous mitochondrial
5) The phenotypic ratio resulting from a dihybrid cross
showing independent assortment is expected to be
(C.1.k)
A) 3:1 B) 9:1:1:3 C) 1:2:1 D) 3:9:9:1 E) 9:3:3:1
6) A testcross is (C.1.i)
A) a mating between two individuals of unknown
genotype.
B) a mating between an individual of unknown
genotype and an individual heterozygous for the trait of
interest.
C) a mating between an individual of unknown
genotype and an individual homozygous dominant for
the trait of interest.
D) a mating between two individuals heterozygous for
the trait of interest.
E) a mating between an individual of unknown
genotype and an individual homozygous recessive for
the trait of interest.
7) Dr. Smith's parents have normal hearing. However,
Dr. Smith has an inherited form of deafness. Deafness is
a recessive trait that is associated with the abnormal
allele d. The normal allele at this locus, associated with
normal hearing, is D. Dr. Smith's parents could have
which of the following genotypes? (C.1.l)
A) DD and DD
B) Dd and DD
C) DD and dd
D) dd and dd
E) Dd and Dd
8) Most genetic disorders of humans are caused by
(C.1.m)
A) multiple alleles.
B) a mutation that occurs in the egg, sperm, or zygote.
C) drinking during pregnancy.
D) dominant alleles.
E) recessive alleles.
9) All the offspring of a cross between a red-flowered
plant and a white-flowered plant have pink flowers.
This means that the allele for red flowers is ________ to
the allele for white flowers. (C.1.i)
A) pleiotropic
B) incompletely dominant
C) codominant
D) dominant
E) recessive
10) A person with AB blood illustrates the principle of
(C.q.i)
A) codominance.
B) pleiotropy.
C) blending inheritance. D) polygenic inheritance.
E) incomplete dominance.
11) Which of the following terms refers to a situation
where a single phenotypic character is determined by
the additive effects of two or more genes? (C.1.m)
A) codominance
B) blending inheritance
C) polygenic inheritanceD) pleiotropy
E) incomplete dominance
12) Genes located close together on the same
chromosomes are referred to as ________ genes and
generally ________. (C.1.h)
A) linked . . . do not sort independently during meiosis
B) associated . . . sort independently during meiosis
C) codependent . . . do not sort independently during
meiosis
D) linked . . . sort independently during meiosis
E) homologous . . . are inherited together
13) Any gene located on a sex chromosome (C.1.j)
A) is called a recessive gene.
B) will exhibit codominance.
C) will exhibit pleiotropy.
D) is called a sex-linked gene.
E) is called a dominant allele.
14) What is the normal complement of sex chromosomes
in a human male? (C.1.j)
A) one X chromosome and one Y chromosome
B) one Y chromosome
C) two Y chromosomes
D) two X chromosomes
E) two X chromosomes and one Y chromosome
15) A color-blind woman marries a man who is not
color-blind. All of their sons, but none of their
daughters, are color-blind. Which of the following
statements correctly explains these results? (C.1.j)
A) The gene for color vision is completely dominant to
the gene for sex determination.
B) The gene for color vision is linked to the Y
chromosome.
C) The gene for color vision is linked to the X
chromosome.
D) The gene for color vision is codominant with the gene
for sex determination.
E) The gene for color vision is incompletely dominant to
the gene for sex determination.
16) Sex-linked conditions are more common in men than
in women because (C.1.j)
A) the sex chromosomes are more active in men than in
women.
B) men acquire two copies of the defective gene during
fertilization.
C) the genes associated with the sex-linked conditions
are linked to the Y chromosome, which determines
maleness.
D) men need to inherit only one copy of the recessive
allele for the condition to be fully expressed.
E) women simply do not develop the disease regardless
of their genetic composition.
17) Which of the following people conducted the
experiments that demonstrated that DNA is the genetic
material of bacteriophages? (C.1.b)
A) Watson and Crick
B) Griffith
C) Pauling
D) Hershey and Chase
E) Franklin
18) The monomers of DNA and RNA are (C.1.a)
A) amino acids.
B) fatty acids.
C) nucleotides.
D) monosaccharides.
E) nucleic acids.
19) The shape of a DNA molecule is most like (C.1.a)
A) a diamond ring.
B) a gold necklace.
C) a set of railroad tracks.
D) the letter X.
E) a twisted rope ladder.
20) If one strand of DNA is CGGTAC, the corresponding
strand would be (C.1.a)
A) GCCAUC B) TAACGT C) CGGTAC. D) GCCTAG
E) GCCATG
21) DNA replication (C.1.a)
A) uses each strand of a DNA molecule as a template for
the creation of a new strand.
B) occurs through the addition of nucleotides to the end
of the DNA molecule.
C) begins when two DNA molecules join together to
exchange segments.
D) results in the formation of four new DNA strands.
E) produces two daughter DNA molecules that are
complementary to each other.
22) Which of the following options best depicts the flow
of information when a gene directs the synthesis of a
cellular component? (C.1.a)
A) DNA > RNA > protein
B) DNA > tRNA > mRNA > protein
C) DNA > amino acid > RNA > protein
D) protein > RNA > DNA
E) RNA > DNA > RNA > protein
23) Which of the following options most accurately lists
the sequence of events in translation? (C.1.a)
A) peptide bond formation > codon recognition >
translocation > termination
B) codon recognition > peptide bond formation >
translocation > termination
C) codon recognition > translocation > peptide bond
formation > termination
D) codon recognition > peptide bond formation >
termination > translocation
E) peptide bond formation > translocation > codon
recognition > termination
24) What combines with sugar and a phosphate group to
form a nucleotide? (EOC C.1.a)
A) amino acid B) deoxyribose
C) glycerol
D) nitrogenous base
25) DNA and RNA have many structural similarities.
Which structure in DNA and RNA is similar? (EOC
C.1.a)
A) purine bases
B) pyrimidine bases
C) type of sugar
D) attached proteins
26) A trisomy of chromosome number 21 causes what
condition? (EOC C.1.m)
A) albinism
B) dwarfism
C) down syndrome
D) color blindness
27) Cystic fibrosis is a genetic disease in which excess
mucus accumulates in the lungs and digestive system of
affected individuals. Males and females must inherit 2
alleles with this mutation to have the disease. What is
the mode of inheritance of cystic fibrosis? (EOC C.1.m)
A) autosomal dominant B) autosomal recessive
C) sex-linked dominant D) sex-linked recessive
28) Which example best illustrates Mendel's law of
independent assortment? (EOC C.1.g)
A) Two short-haired cats produce a litter of 4 kittens
including 1 long-haired and 3 short-haired
B) A color-blind man and a woman with normal vision
produce a son with normal vision and a color-blind
daughter.
C) A tall purple-flowered pea plant and a short whiteflowered pea plant are crossed, producing offspring
including tall white-flowered pea plants.
D) A red-flowered snapdragon and a white-flowered
snapdragon are crossed, producing offspring with pink
flowers.
29) Patch, a short-haired cat, has black and orange spots.
Two distinct autosomal gene loci produce this pattern.
One gene locus produces spots as a recessive trait (ss).
Another gnee locus determines the color of the spots.
Homozygous BB cats have black spots, while
homozygous GG cats have orange spots. Heterozygous
cats have black and orange spots. According to the law
of independent assortment, Patch would most likely
produce gametes in what proportion? (EOC C.1.g)
A) All ss
B) All BGss
C) Half BS and half GS D) Half Bs and half Gs
30) In humans, pigmented skin is dominant to nonpigmented skin (albinism). What is the genotype of an
individual with albinism? (EOC C.1.i)
A) carrier
B) heterozygous
C) homozygous dominant D) homozygous recessive
31) Jeanine inherited 2 alleles for round eye shape and
has round eye shape. Her brother inherited 1 allele for
round eye shape and 1 allele for almond eye shape and
has almond eye shape. What type of trait is round eye
shape? (EOC C.1.i)
A) co-dominant B) dominant C) recessive D) sex-linked
32) Horses born to 2 palomino (golden-coated) horses
have a 25% chance of having a white coat, a 25% chance
of having a chesnut (brown) coat, and a 50% chance of
having a palomino coat. Which description of
inheritance best explains the coat-color trait in these
horses? (EOC C.1.i)
A) palomino coat color is a recessive trait
B) palomino coat color is a dominant trait
C) coat color is an incompletely dominant trait
D) coat color is a sex-linked trait
33) In human, red-green color blindness is a recessive,
sex-linked trait. The chromosomes and alleles associated
with color blindness are represented in this chart.
X = X chromosome
Y = Y chromosome
B = allele for normal color vision
b = allele for color blindness
Which child could NOT be born to these parents: a
female (XBXb) and a male (XBY)? (EOC C.1.j)
A) color-blind daughter
B) color-blind son
C) daughter with normal color vision
D) son with normal color vision
34) The genotype for F1 individuals from a dihybrid
cross is AaBb X AaBB. What is the expected ratio of
AaBb individuals in the F2 generation? (EOC C.1.k)
A) 8/16 B) 4/16 C) 2/16 D) 1/16
35) Keisha passes a local dairy farm that has many
brown cows, bout only a few white cows. A dominant
allele produces brown hair in cows and a recessive allele
produces white hair. Which characteristic of any brown
cow can Keisha identify? (EOC C.1.l)
A) the genotype of both of the cow's parents
B) the genotype of the cow's hair color
C) the phenotype of both of the cow's parents
D) the phenotyep of the cow's hair color
36) Adrenoleukodystrophy (ALD) is a sex-linked
recessiv etrait that affects the nervous system. In one
family, the father, mother, daughter, and elder son do
not have ALD, while the younger son has ALD. Who
must be a carrier of the ALD allele? (EOC C.1.l)
A) father B) mother C) daughter D) elder son
39) Alkaptonuria is a genetic disorder of protein
metabolism.
The disorder is determined by 2 alleles at 1 locus.
37) This pedigree shows 3 generations of a family and
the family's incidences of color blindness, a sex-lnked,
recessive trait.
What is the genotype for individual 1 in the diagram?
(EOC C.1.l)
A) AA or Aa
B) AA
C) Aa
D) aa
40) This chart shows the RNA sequences that code for
various amino acids.
Which pair of females must have the same genotype?
(EOC C.1.l)
A) 3 and 5 B) 7 and 11 C) 8 and 13 D) 10 and 14
38) Two black guinea pigs bred and produced 3 black
offspring and 2 albino offspring. Assuming no
mutations, which guinea pigs must be heterozygous?
(EOC C.1.l)
A) all 3 black offspring
B) exactly 2 of the black offspring
C) both albino offspring
D) both parents
The mRNA sequence ACU codes for the amino acid Thr.
A mutations occurs, and the resulting mRNA sequence
is AUU. What amino acid will replace Thr?
A) Val
B) Met
C) Ile
D) Ala
Name_________________________________________________________
Heredity Unit Review
Constructed Response. Write your answer in the space provided or on a separate sheet of paper.
41) A biologist identifies the DNA sequence, or gene, that codes for a protein that stops the production of eggs in
mosquitoes. She labels this gene Sequence 1. During her investigation of the replication, transcription , and
translation of the gene, she observes mosquitoes in which the protein coded by this gene does not function. She
labels the DNA sequence for this version Sequence 2. The first table shows one DNA strand for each gene
sequence. Use the mRNA Codon Chart to complete the following tasks. (EOC C.1.a, C.1.c, C.1.d)
Using your understanding of mutations and the genetic code, analyze these nucleotide sequences. As part of
your answer, be sure to :
. Determine the mRNA sequence that complements Sequence 1.
. Use the mRNA Codon Chart to translate the mRNA sequence in the previous bullet into an amino acid
chain.
. Identify the type of mutation in Sequence 2, describe how this mutation specifically affects the amino acid
sequence of the protein, and describe how this change results in a protein that does not function correctly.