BIO1108 UNIT 4 EXAM QUESTIONS
WITH 100% CORRECT ANSWERS
What is the meaning of Darwin's expression "descent with modification"? - Answer-
Descent with modification refers to evolutionary change over time.
Males of different species of the fruit fly Drosophila that live in the same parts of the
Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting
other males and making stylized movements that attract females. What type of
reproductive isolation does this represent? - Answer- behavioral isolation
Which of the following statements supports the hypothesis of "an RNA world" on early
Earth? - Answer- Some RNA molecules are important catalysts in modern cells.
Fossilized stromatolites - Answer- resemble structures formed by bacterial communities
that are found today in some warm, shallow, salty bays
A paleontologist finds a new tyrannosaur in a site she is excavating, and wishes to date
the fossil. What is the most likely method she will use? - Answer- She will infer the age
of the fossil by dating layers of volcanic rock above and below the stratum containing
the fossil.
Natural selection changes allele frequencies because some _______ survive and
reproduce more successfully than others. - Answer- individuals
A genetic change that caused a certain Hox gene to be expressed along the tip of a
vertebrate limb bud instead of farther back helped make possible the evolution of the
tetrapod limb. This type of change is illustrative of - Answer- a change in a
developmental gene or in its regulation that altered the spatial organization of body
parts.
A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the
gametes produced in the population contain the A1 allele. If the population is in Hardy-
Weinberg equilibrium, what proportion of the flies carry both A1 and A2? - Answer- 0.42
According to the punctuated equilibria model, - Answer- most new species accumulate
their unique features relatively rapidly as they come into existence, then change little for
the rest of their duration as a species.
Which of the following best demonstrates the unity among all organisms? - Answer- the
structure and function of DNA
, Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species.
Recently, these birds have been classified as eastern and western forms of a single
species, the yellow-rumped warbler. Which of the following pieces of evidence, if true,
would be cause for this reclassification? - Answer- The two forms interbreed often in
nature, and their offspring have good survival and reproduction.
Plant species A has a diploid number of 12. Plant species B has a diploid number of 16.
A new species, C, arises as an allopolyploid from A and B. The diploid number for
species C would probably be - Answer- 28
The universal genetic language of DNA is common to virtually all organisms on Earth,
however diverse. What is the best explanation for this fact? - Answer- All living things
share a common genetic language of DNA because they share a common ancestry.
In 1959, doctors began using the powerful antibiotic methicillin to treat infections of
Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus
(MRSA) appeared. How did the resistant strains of S. aureus emerge? - Answer-
Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein
that was not affected by methicillin survived the methicillin treatments and reproduced at
higher rates than did other individuals. Over time, these resistant individuals became
increasingly common.
Which factor most likely caused animals and plants in India to differ greatly from species
in nearby southeast Asia? - Answer- India was a separate continent until 45 million
years ago.
Which of the following is an example of qualitative data? - Answer- The fish swam in a
zigzag motion.
How do the data from sites 9-11 compare with the data from the sites within the Sound?
- Answer- The frequency of the lap94 allele is higher at sites 9-11 than it is within the
Sound; however, the northeast edge of the Sound has nearly the same frequency of the
lap94 allele as do sites 9-11.
What hypothesis would explain the patterns in the data? - Answer- The frequency of the
lap94 allele at different sites results from an interaction between selection and gene
flow.
Select the correct statement about the process of scientific inquiry. - Answer- It is
possible to test hypotheses, such as those involving historical events, without
conducting experiments.
Within six months of effectively using methicillin to treat S. aureus infections in a
community, all new infections were caused by MRSA. How can this result best be
explained? - Answer- Some drug-resistant bacteria were present at the start of
treatment, and natural selection increased their frequency.
WITH 100% CORRECT ANSWERS
What is the meaning of Darwin's expression "descent with modification"? - Answer-
Descent with modification refers to evolutionary change over time.
Males of different species of the fruit fly Drosophila that live in the same parts of the
Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting
other males and making stylized movements that attract females. What type of
reproductive isolation does this represent? - Answer- behavioral isolation
Which of the following statements supports the hypothesis of "an RNA world" on early
Earth? - Answer- Some RNA molecules are important catalysts in modern cells.
Fossilized stromatolites - Answer- resemble structures formed by bacterial communities
that are found today in some warm, shallow, salty bays
A paleontologist finds a new tyrannosaur in a site she is excavating, and wishes to date
the fossil. What is the most likely method she will use? - Answer- She will infer the age
of the fossil by dating layers of volcanic rock above and below the stratum containing
the fossil.
Natural selection changes allele frequencies because some _______ survive and
reproduce more successfully than others. - Answer- individuals
A genetic change that caused a certain Hox gene to be expressed along the tip of a
vertebrate limb bud instead of farther back helped make possible the evolution of the
tetrapod limb. This type of change is illustrative of - Answer- a change in a
developmental gene or in its regulation that altered the spatial organization of body
parts.
A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the
gametes produced in the population contain the A1 allele. If the population is in Hardy-
Weinberg equilibrium, what proportion of the flies carry both A1 and A2? - Answer- 0.42
According to the punctuated equilibria model, - Answer- most new species accumulate
their unique features relatively rapidly as they come into existence, then change little for
the rest of their duration as a species.
Which of the following best demonstrates the unity among all organisms? - Answer- the
structure and function of DNA
, Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species.
Recently, these birds have been classified as eastern and western forms of a single
species, the yellow-rumped warbler. Which of the following pieces of evidence, if true,
would be cause for this reclassification? - Answer- The two forms interbreed often in
nature, and their offspring have good survival and reproduction.
Plant species A has a diploid number of 12. Plant species B has a diploid number of 16.
A new species, C, arises as an allopolyploid from A and B. The diploid number for
species C would probably be - Answer- 28
The universal genetic language of DNA is common to virtually all organisms on Earth,
however diverse. What is the best explanation for this fact? - Answer- All living things
share a common genetic language of DNA because they share a common ancestry.
In 1959, doctors began using the powerful antibiotic methicillin to treat infections of
Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus
(MRSA) appeared. How did the resistant strains of S. aureus emerge? - Answer-
Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein
that was not affected by methicillin survived the methicillin treatments and reproduced at
higher rates than did other individuals. Over time, these resistant individuals became
increasingly common.
Which factor most likely caused animals and plants in India to differ greatly from species
in nearby southeast Asia? - Answer- India was a separate continent until 45 million
years ago.
Which of the following is an example of qualitative data? - Answer- The fish swam in a
zigzag motion.
How do the data from sites 9-11 compare with the data from the sites within the Sound?
- Answer- The frequency of the lap94 allele is higher at sites 9-11 than it is within the
Sound; however, the northeast edge of the Sound has nearly the same frequency of the
lap94 allele as do sites 9-11.
What hypothesis would explain the patterns in the data? - Answer- The frequency of the
lap94 allele at different sites results from an interaction between selection and gene
flow.
Select the correct statement about the process of scientific inquiry. - Answer- It is
possible to test hypotheses, such as those involving historical events, without
conducting experiments.
Within six months of effectively using methicillin to treat S. aureus infections in a
community, all new infections were caused by MRSA. How can this result best be
explained? - Answer- Some drug-resistant bacteria were present at the start of
treatment, and natural selection increased their frequency.
