HS 4212 Final Exam Questions and
Answers | 2026 Update | 100% Correct
Why does genetic drift affect small populations more than large ones?
a. Genetic drift drives the extinction of many species
b. Random changes in allele frequencies from one generation to the next can produce
large changes in allele frequencies over time, allowing harmful alleles to increase in
frequency
c. Genetic drift in fact affects larger populations more than smaller ones
d. Genetic drift drives the movement of many species worldwide causing populations
size to reduce even further
e. Genetic drift affects all populations equally -CORRECTANSWER b. Random
changes in allele frequencies from one generation to the next can produce large
changes in allele frequencies over time, allowing harmful alleles to increase in
frequency
DNA replication occurs
a. before both mitosis and meiosis.
b. only before mitosis.
c. only before meiosis.
d. during chromosome condensation.
e. during G2. -CORRECTANSWER a. before both mitosis and meiosis.
The accompanying diagram shows how a population of fruit flies (Drosophila
melanogaster) can be selected for individuals with high and low numbers of bristles on
their abdomens from an initial population with intermediate numbers of bristles. Which
of the following statements regarding artificial selection and natural selection is true?
a. Both artificial selection and natural selection act on genes already present in the gene
pool of the population.
b. Artificial selection acts on genes already present in the gene pool, whereas natural
selection produces mutations in the genes.
c. Natural selection acts on genes already present in the gene pool, whereas artificial
selection produces mutations in the genes.
d. Phenotypic variation is only seen in artificial selection.
e. Phenotypic variation is only seen in natural selection. -CORRECTANSWER a. Both
artificial selection and natural selection act on genes already present in the gene pool of
the population.
, According to the ________, our feelings of self-esteem evolved to monitor the degree to
which we are accepted by others.
a. Genetic theory
b. Sociometer theory
c. Depression theory
d. Reproductive theory -CORRECTANSWER b. Sociometer theory
Which of the following statements about mutations is false?
a. Mutation rates are very low for most loci
b. Mutations are random with respect to the adaptive needs of organisms
c. Most mutations are either harmful or neutral
d. Only rarely does a human carry a new mutation in his or her genome
e. The current human population carries billions of new mutations that were not present
in previous generations -CORRECTANSWER
Which of the following statements about allele frequencies is true?
a. It is possible to have a negative allele frequency
b. Allele frequencies can be greater than 1 in some populations
c. The sum of all allele frequencies is 0
d. All of the above
e. None of the above -CORRECTANSWER e. None of the above
Which of the following correctly indicates the complementary base pairing of adenine in
DNA and RNA?
a. adenine with thymine in both DNA and RNA
b. adenine with uracil in DNA and with thymine in RNA
c. adenine with thymine in DNA and with uracil in RNA
d. adenine with cytosine in DNA and with guanine in RNA
e. adenine with guanine in DNA and with cytosine in RNA -CORRECTANSWER
adenine with thymine in DNA and with uracil in RNA
A field experiment is conducted to test for a heterozygote advantage in the survival of a
mustard plant. When heterozygotes for the A locus are first crossed, the yield is 200 AA,
400 Aa, and 200 aa ( i.e., a ratio of 1:2:1). In trial 1, 35 AA, 44 Aa, and 23 aa plants
survive. In trial 2, 25 AA, 68 Aa, and 21 aa plants survive. Based on these results, which
of the following statements is true?
a. Only trial 1 shows heterozygote advantage.
b. Only trial 2 shows heterozygote advantage.
c. Both trials 1 and 2 show heterozygote advantage.
d. Neither trial shows heterozygote advantage.
Answers | 2026 Update | 100% Correct
Why does genetic drift affect small populations more than large ones?
a. Genetic drift drives the extinction of many species
b. Random changes in allele frequencies from one generation to the next can produce
large changes in allele frequencies over time, allowing harmful alleles to increase in
frequency
c. Genetic drift in fact affects larger populations more than smaller ones
d. Genetic drift drives the movement of many species worldwide causing populations
size to reduce even further
e. Genetic drift affects all populations equally -CORRECTANSWER b. Random
changes in allele frequencies from one generation to the next can produce large
changes in allele frequencies over time, allowing harmful alleles to increase in
frequency
DNA replication occurs
a. before both mitosis and meiosis.
b. only before mitosis.
c. only before meiosis.
d. during chromosome condensation.
e. during G2. -CORRECTANSWER a. before both mitosis and meiosis.
The accompanying diagram shows how a population of fruit flies (Drosophila
melanogaster) can be selected for individuals with high and low numbers of bristles on
their abdomens from an initial population with intermediate numbers of bristles. Which
of the following statements regarding artificial selection and natural selection is true?
a. Both artificial selection and natural selection act on genes already present in the gene
pool of the population.
b. Artificial selection acts on genes already present in the gene pool, whereas natural
selection produces mutations in the genes.
c. Natural selection acts on genes already present in the gene pool, whereas artificial
selection produces mutations in the genes.
d. Phenotypic variation is only seen in artificial selection.
e. Phenotypic variation is only seen in natural selection. -CORRECTANSWER a. Both
artificial selection and natural selection act on genes already present in the gene pool of
the population.
, According to the ________, our feelings of self-esteem evolved to monitor the degree to
which we are accepted by others.
a. Genetic theory
b. Sociometer theory
c. Depression theory
d. Reproductive theory -CORRECTANSWER b. Sociometer theory
Which of the following statements about mutations is false?
a. Mutation rates are very low for most loci
b. Mutations are random with respect to the adaptive needs of organisms
c. Most mutations are either harmful or neutral
d. Only rarely does a human carry a new mutation in his or her genome
e. The current human population carries billions of new mutations that were not present
in previous generations -CORRECTANSWER
Which of the following statements about allele frequencies is true?
a. It is possible to have a negative allele frequency
b. Allele frequencies can be greater than 1 in some populations
c. The sum of all allele frequencies is 0
d. All of the above
e. None of the above -CORRECTANSWER e. None of the above
Which of the following correctly indicates the complementary base pairing of adenine in
DNA and RNA?
a. adenine with thymine in both DNA and RNA
b. adenine with uracil in DNA and with thymine in RNA
c. adenine with thymine in DNA and with uracil in RNA
d. adenine with cytosine in DNA and with guanine in RNA
e. adenine with guanine in DNA and with cytosine in RNA -CORRECTANSWER
adenine with thymine in DNA and with uracil in RNA
A field experiment is conducted to test for a heterozygote advantage in the survival of a
mustard plant. When heterozygotes for the A locus are first crossed, the yield is 200 AA,
400 Aa, and 200 aa ( i.e., a ratio of 1:2:1). In trial 1, 35 AA, 44 Aa, and 23 aa plants
survive. In trial 2, 25 AA, 68 Aa, and 21 aa plants survive. Based on these results, which
of the following statements is true?
a. Only trial 1 shows heterozygote advantage.
b. Only trial 2 shows heterozygote advantage.
c. Both trials 1 and 2 show heterozygote advantage.
d. Neither trial shows heterozygote advantage.
