Download Unit IIC Practice Exam

Unit IIC Practice Exam (v. 2.0: KEY)
1.
Which of the following best describes the pattern of punctuated equilibrium in evolution? (PT1-17)
a. Speciation events occur relatively rapidly
b. Small changes that accumulate over long periods of time lead to the formation of a new species and
the extinction of the old species.
c. Small changes that accumulate over long periods of time lead to the divergence of one species into
two or more species.
d. Speciation occurs when random changes accumulate over long periods of time
e. Geographic isolation is the predominant mechanism of speciation.
2.
A recessive trait appears in 81% of the individuals in a population that is in Hardy-Weinberg equilibrium.
What percent of the population in the next generation is expected to be homozygous dominant? (PT1-24)
a. 1%
b. 9%
c. 18%
d. 19%
e. 81%
3.
Two sympatric species of pine trees release their pollen during different months. This is an example of ______.
(PT1-37)
a.
b.
c.
d.
e.
Habitat isolation
Temporal isolation
Behavioral isolation
Mechanical isolation
Geographic isolation
4.
A dominant trait appears in 19% of the individuals in a population that is in Hardy-Weinberg equilibrium.
What percent of the population in the next generation is expected to be homozygous dominant? (PT2-7)
a. 1%
b. 9%
c. 18%
d. 19%
e. 81%
5.
The size of a population of mice on an isolated island has remained constant for 50 years. What is the average
number of offspring that each breeding pair produces during its lifetime that survives to reproductive
maturity and reproduces? (PT2-28)
a. 0
b. 1
c. 2
d. 10-20
e. more than 20
The next two questions refer to the following graph which shows phenotypic changes for three unrelated
species that occur in different parts of the world. Species 2 evolves into new species 3 and species 4 evolves
into new species 5.
6. The evolution of species 3 from species 2
illustrates ______. (PT2-75)
a. Phyletic gradualism
b. Genetic drift
c. Punctuated equilibrium
d. Co-evolution
e. Adaptive radiation
7. Which of the following illustrates directional
selection? (PT2-76)
a. Species 1 only
b. Species 2 only
c. Species 3 only
d. Species 4 only
e. Species 1 and 4
The next questions refers to the following graph.
In 1650, several families settle on an isolated island and their descendants survive without interactions from any
mainland populations. During this period of time, the frequency of children born deaf is shown in the following graph. In
1900, contact with the mainland populations is re-established, and some families move away from the island while new
families from the mainland arrive.
8.
Which of the following best describes the cause for
the changes in frequency of deafness between 1900
and 1950? (PT2-83)
a. Mutation
b. Gene flow
c. Genetic drift
d. Founder effect
e. Balanced polymorphism
9.
Which of the following is a correct statement about
mutations? (1994-9)
a. They are a source of variation for evolution
b. They drive evolution by creating mutation
pressures
c. They are irreversible
d. They occur in germ cells but not in somatic cells
e. They are most often beneficial to the organisms in which they occur
10. Although the seal and the penguin both have streamlined, fishlike bodies with a layer of insulating fat, they
are not closely related. This similarity results from _____. (1994-28)
a. Convergent evolution
b. Adaptive radiation
c. Homologous evolution
d. Coevolution
e. Parallel evolution
11. Which of the following is probably the best explanation for the fat that Antarctic penguins cannot fly, although
there is some evidence that millions of years ago their ancestors could do so? (1994-39)
a. Penguins live on land and feed in water; therefore they have no need to fly.
b. The Antarctic home of penguins is flat and barren; therefore there is no place to fly
c. Ancestral penguins without large wings were better able to swim and feed in the water; therefore
they passed their genes for shorter wing structure on to their offspring.
d. Ancestral penguins did not use their wings for long periods of time; therefore today’s penguins have
only time, nonfunctional wings
e. The cold and wind of Antarctic make flight impossible; therefore penguins that live there have lost
the ability to fly.
The next question refers to the following scenario.
In a certain flock of sheep, 4 percent of the population has black wool and 96 percent has white wool. Assume that the
population is in Hardy-Weinberg equilibrium.
12. What percentage of the population is homozygous for white wool? (1994-50)
a. 20%
b. 40%
c. 64%
d. 80%
e. 96%
13. The different species of finches on the Galapagos Islands are believed to have arisen as a result of natural
selection acting on populations of finches that experienced _____. (2002-4)
a. Convergent evolution
b. Gene flow
c. The bottleneck effect
d. Geographic isolation
e. Hybrid sterility
The next two questions refer to the following scenario. For each group of questions below consists of five
lettered headings followed by a list of numbered phrases or sentences. For each numbered phrase or
sentence select the one heading that is most closely related to it and fill in the corresponding correct answer.
Each heading may be used once, more than once, or not at all in each group.
(A) Comparative biochemistry
(B) Comparative anatomy
(C) Comparative embryology
(D) Geographical distribution
(E) Paleontology
From the fields of study listed above, choose the field that has provided each of the following pieces of evidence that
biological evolution has occurred.
14. Peripatus has claws like an insect and paired nephridia like a segmented worm. (1994-69) (B)
15. Most human diabetics can use insulin derived either from pigs or humans. (1994-70) (A)
The next two questions refer to the following graph.
A moth’s color is controlled by two alleles, G and g, at a
single locus. G (gray) is dominant to g (white). A large
population of moths was studied, and the frequency of the G
allele is the population over time was documented, as shown
in the figure. In 1980, a random sample of 2,000 pupae was
collected and moths were allowed to emerge.
16. Assuming that the population was in HardyWeinberg equilibrium for the G locus, what
percentage of the gray moths that emerged in 1980
was heterozygous? (2002-108)
a. 0%
b. 25%
c. 33%
d. 67%
e. 100%
17. Assuming that the population was in Hardy-Weinberg equilibrium for the G locus, what was the frequency of
the allele G in the gray moths that emerged in 1980? (2002-109)
a. 0.33
b. 0.50
c. 0.67
d. 0.75
e. 1.00
18. The best evidence that the giant panda is more closely related to bears than is the raccoon-like lesser panda
involves _____. (2008-5)
a. Comparative anatomy
b. Comparative embryology
c. DNA sequence comparisons
d. Behavioral similarities
e. Fossil records
19. All of the following statements concerning the theory of evolution by natural selection are true EXCEPT _____.
(2008-13)
a.
b.
c.
d.
e.
Organisms produce far more offspring than are required for replacement
The individuals in a population show variation in survivability and in their ability to cope with
environmental stress
The number of offspring that survive to reproduce varies among individuals
The bodies of organisms in a population change by use and disuse, and the changes are inherited by
the next generation.
Some of the variation in adaptation is the result of genetic differences that may be passed on to the
next generation.
20. The functional similarity of the mandibles (hinged jaws) of insects and those of mammals is an example of
_____ (2008-32)
a. Homology
b. Analogy
c. Divergent evolution
d. Adaptive radiation
e. Punctuated equilibrium
21. In evolutionary terms, which of the following organisms is the most successful? (2008-45)
a. The one that lives the longest
b. The one that grows most rapidly
c. The one that leaves the greatest number of offspring that survive to reproduce
d. The one that has the best characteristics for the current environment
e. The one that has the biggest territory
22. If a population is at Hardy-Weinberg equilibrium, which of the following can be predicted for the recessive
alleles in the population? (2008-52)
a. They will eventually disappear
b. They will be selected against
c. They will be maintained at the same frequency
d. They will be expressed in the heterozygous condition
e. They will become dominant
23. A large assemblage of land snails is subdivided into two populations (A and B) by a river that effectively
isolates the two populations for an indefinitely long period. From an evolutionary standpoint, which of the
following is the LEAST likely to occur in the two populations? (2008-54)
a. Populations A and B will eventually differ in their ecological requirements.
b. Population A may ultimately breed at a different time of the year than population B does.
c. Population A may undergo instantaneous speciation by the doubling of its chromosome numbers
(polyploidy)
d. Under laboratory conditions, cross-fertilizations between members of the two populations may be
successful even after a long period of geographical separation
e. The two populations may become morphologically dissimilar.
The next two questions refer to the following scenario.
A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several
generations, 49 percent of the animals display a recessive trait (bb), the same percentage as at the beginning of the
breeding program. The rest of the animals show the dominant phenotype, with heterozygous indistinguishable from the
homozygous dominants.
24. What is the most reasonable conclusion that can be drawn from the fact that the frequency of allele b has not
changed over time? (2010-38)
a. The population is undergoing genetic drift
b. The two phenotypes are equally adaptive under laboratory conditions
c. The genotype BB is lethal
d. There has been a high rate of mutation of allele B to allele b
e. There has been sexual selection favoring allele b
25. What proportion of the population is heterozygous (Bb) for this trait? (2010-40)
a. 0.51
b. 0.42
c. 0.21
d. 0.09
e. 0.07
The next two questions refer to the following scenario and table.
Individuals of a particular species of ground beetle are either light-tan or dark-brown. Light-tan beetles are predominant
in habitats with light-colored sandy soils, and dark-brown beetles are predominant in habitats with dark-colored loam
soils. In an experiment designed to determine the survival rates of light-tan beetles and dark-brown beetles in different
habitats, 500 light-tan beetles and 500 dark-brown beetles were released in each of four habitats. Each beetle had been
marked with a small spot of red paint on the underside of its abdomen before it was released. One week after the beetles
had been released, any marked beetles that could be found were recaptured. The results are presented in the table below.
It is assumed that differences in the numbers of beetles recaptured are directly related to differences in survival rates.
Habitat 1
Sandy soil, no
insectivorous birds
present
Color of Beetle
Number
Released
Number
Recaptured
Light-tan
Habitat 2
Sandy soil, insectivorous
birds present
Light-tan
500
Darkbrown
500
130
114
Habitat 3
Sandy soil, no
insectivorous birds
present
Habitat 4
Sandy soil, insectivorous
birds present
Lighttan
500
Darkbrown
500
Light-tan
500
Darkbrown
500
500
Darkbrown
500
123
22
65
74
13
87
26. Which of the following processes best explains why fewer light-tan beetles than dark-brown beetles were
captured in Habitat 4? (2010-43)
a. Immigration
b. Genetic drift
c. Mutation
d. Adaptive radiation
e. Predation
27. If all insectivorous birds and remaining beetles were removed from Habitat 2 and 500 additional dark-brown
beetles and 500 additional light-tan beetles were then released into Habitat 2, which of the following is the
best estimate of the number of additional dark-brown beetles that would be expected to be recaptured in
Habitat 2 after one more week? (2010-44)
a. 0
b. 22
c. 122
d. 120
e. 220
f. 500
28. Which of the following statements best summarizes organic evolution as it is viewed by modern
evolutionists? (2010Sample-3)
a. It is goal directed
b. Is represents the results of selection for acquired characteristics
c. It is synonymous with the process of gene flow
d. It is the descent of humans from the present-day great apes
e. It is the differential survival and reproduction of certain phenotypes
29. Two fossil vertebrates, each representing a different class, are found in the undisturbed rock layers of a cliff.
One fossil is a representative of the earliest amphibians. The other fossil is most likely to be _____. (2010Sample11)
a.
b.
c.
d.
e.
A dinosaur
A fish
An insectivorous mammal
A snake
A bird
The next question refers to the following scenario and graphs.
30. In a hypothetical population of beetles, there is a wide variety of color, matching the range of coloration of the
tree trunks on which the beetles hide from predators. The graphs below illustrate four possible changes to
the beetle population as a result of a change in the environment due to pollution that darkened the tree
trunks. (2012-21)
a. The coloration range shifted toward more light-colored beetles, as in Diagram I. The pollution helped
the predators find the darkened tree trunks.
b. The coloration in the population split into two extremes, as in Diagram II. Both the lighter-colored
and the darker-colored beetles were able to hide on the darker tree trunks.
c. The coloration range became narrower, as in Diagram III. The predators selected beetles at the color
extremes.
d. The coloration in the population shifted toward more darker-colored beetles, as in Diagram IV. The
lighter-colored beetles were found more easily by the predators than were the darker-colored
beetles.