BIO 148 FINAL EXAM QUESTIONS
AND ANSWERS 2026
Why does the presence of extinct forms and transitional features in the fossil record
support the pattern component of the theory of evolution by natural selection?
A. It supports the hypothesis that individuals change over time.
B. It supports the hypothesis that weaker species are eliminated by natural selection.
C. It supports the hypothesis that species evolve to become more complex and better
adapted over time.
D. It supports the hypothesis that species change over time. - ANSWERSD
Which pieces of evidence showed that whales evolved from terrestrial dwelling
mammals?
A. Some whales have vestigial hip and limb bones.
B. A phylogeny of living whales puts hippos as their closest living relative.
C. Fossils of cetaceans showed the transition from land to aquatic forms.
D. All of the above. - ANSWERSD
People will breed dogs for certain desirable traits. This is known as......
A. Natural selection
B. Directional selection
C. Artificial selection
D. Sexual selection - ANSWERSC
Artificial selection can not be considered evolution because it does not change allele
frequencies.
True or false? - ANSWERSFalse
Which individual in the following scenarios is the most fit?
A. A frog that lives 5 years and leaves 20 fertile offspring.
B. A frog that lives 20 years and leaves 10 fertile offspring
C. A frog that survives being run over by a car, lives 10 years, and produces 2 fertile
offspring.
D. A frog that lives for 1 year and produces 15 offspring, but not all are fertile. -
ANSWERSA
Which of the following is true in regards to antibiotic use and bacterial evolution?
A. Bacteria mutated to become resistant in response to the presence of the antibiotics.
B. If antibiotic use was discontinued, bacteria will mutate to the non-mutant form.
C. Genetic variation for antibiotic resistance was present in the population before the
antibiotic was used.
D. The antibiotic resistance arose in independent bacteria; it was not inherited. -
ANSWERSC
, During very rainy years on the Galapagos Islands, very small seeds are abundant. What
do you think will happen to beak depth in the finch population?
A. The frequency of individuals with deep beaks will increase in the population.
B. Beak depth will not change in the population.
C. Both deeper beaks and smaller beaks will increase in frequency in the population.
D. Smaller depth beaks will increase in frequency in the population. - ANSWERSD
Which of the following statements is correct?
A. When individuals change in response to challenges from the environment, their
altered traits are passed on to offspring.
B. Species are created independently of each other and do not change over time.
C. Populations-not individuals-change when natural selection occurs.
D. The traits of populations become more perfect over time. - ANSWERSC
The gene sonic hedgehog is expressed in both the developing limb and the developing
facial bones, with switches controlling this expression. What would happen if the switch
for limb expression was deleted?
A. Shh would still be expressed in both the limbs and the jaw.
B. Shh would be expressed only in the limbs.
C. Shh would not be expressed in either the limbs or the jaw.
D. Shh would be expressed only in the jaw. - ANSWERSD
Which mechanism of natural selection shifts the average phenotype of a population in
one direction?
A. Directional selection
B. Stabilizing selection
C. Disruptive selection
D. Sexual selection - ANSWERSA
The Dunkers are a religious group that moved from Germany to Pennsylvania in the
mid-1700s. They do not marry with members outside their own immediate community.
Today, the Dunkers are genetically unique and differ in gene frequencies, at many loci,
from all other populations including their original homeland. Which of the following likely
explains the genetic uniqueness of this population?
A. Sexual selection
B. Stabilizing selection
C. Mutation and natural selection
D. Founder effect and genetic drift - ANSWERSD.
Mutation is the ultimate source of genetic variability. Why is this statement correct?
A. DNA polymerase is remarkably accurate.
B. Mutations are usually removed from the population.
C. Mutation is the only source of new alleles.
D. Mutation occurs in response to natural selection. It generates the alleles that are
required for a population to adapt to a particular habitat. - ANSWERSC
AND ANSWERS 2026
Why does the presence of extinct forms and transitional features in the fossil record
support the pattern component of the theory of evolution by natural selection?
A. It supports the hypothesis that individuals change over time.
B. It supports the hypothesis that weaker species are eliminated by natural selection.
C. It supports the hypothesis that species evolve to become more complex and better
adapted over time.
D. It supports the hypothesis that species change over time. - ANSWERSD
Which pieces of evidence showed that whales evolved from terrestrial dwelling
mammals?
A. Some whales have vestigial hip and limb bones.
B. A phylogeny of living whales puts hippos as their closest living relative.
C. Fossils of cetaceans showed the transition from land to aquatic forms.
D. All of the above. - ANSWERSD
People will breed dogs for certain desirable traits. This is known as......
A. Natural selection
B. Directional selection
C. Artificial selection
D. Sexual selection - ANSWERSC
Artificial selection can not be considered evolution because it does not change allele
frequencies.
True or false? - ANSWERSFalse
Which individual in the following scenarios is the most fit?
A. A frog that lives 5 years and leaves 20 fertile offspring.
B. A frog that lives 20 years and leaves 10 fertile offspring
C. A frog that survives being run over by a car, lives 10 years, and produces 2 fertile
offspring.
D. A frog that lives for 1 year and produces 15 offspring, but not all are fertile. -
ANSWERSA
Which of the following is true in regards to antibiotic use and bacterial evolution?
A. Bacteria mutated to become resistant in response to the presence of the antibiotics.
B. If antibiotic use was discontinued, bacteria will mutate to the non-mutant form.
C. Genetic variation for antibiotic resistance was present in the population before the
antibiotic was used.
D. The antibiotic resistance arose in independent bacteria; it was not inherited. -
ANSWERSC
, During very rainy years on the Galapagos Islands, very small seeds are abundant. What
do you think will happen to beak depth in the finch population?
A. The frequency of individuals with deep beaks will increase in the population.
B. Beak depth will not change in the population.
C. Both deeper beaks and smaller beaks will increase in frequency in the population.
D. Smaller depth beaks will increase in frequency in the population. - ANSWERSD
Which of the following statements is correct?
A. When individuals change in response to challenges from the environment, their
altered traits are passed on to offspring.
B. Species are created independently of each other and do not change over time.
C. Populations-not individuals-change when natural selection occurs.
D. The traits of populations become more perfect over time. - ANSWERSC
The gene sonic hedgehog is expressed in both the developing limb and the developing
facial bones, with switches controlling this expression. What would happen if the switch
for limb expression was deleted?
A. Shh would still be expressed in both the limbs and the jaw.
B. Shh would be expressed only in the limbs.
C. Shh would not be expressed in either the limbs or the jaw.
D. Shh would be expressed only in the jaw. - ANSWERSD
Which mechanism of natural selection shifts the average phenotype of a population in
one direction?
A. Directional selection
B. Stabilizing selection
C. Disruptive selection
D. Sexual selection - ANSWERSA
The Dunkers are a religious group that moved from Germany to Pennsylvania in the
mid-1700s. They do not marry with members outside their own immediate community.
Today, the Dunkers are genetically unique and differ in gene frequencies, at many loci,
from all other populations including their original homeland. Which of the following likely
explains the genetic uniqueness of this population?
A. Sexual selection
B. Stabilizing selection
C. Mutation and natural selection
D. Founder effect and genetic drift - ANSWERSD.
Mutation is the ultimate source of genetic variability. Why is this statement correct?
A. DNA polymerase is remarkably accurate.
B. Mutations are usually removed from the population.
C. Mutation is the only source of new alleles.
D. Mutation occurs in response to natural selection. It generates the alleles that are
required for a population to adapt to a particular habitat. - ANSWERSC
