Evolution Practice Test Advanced Placement Biology
Choose the one best answer which best completes each of the following
statements or answers each of the following questions. (2 pts. @)
1. In a population that is in Hardy-Weinberg equilibrium, the frequency of the
recessive homozygous genotype is 0.09. The frequency of individuals
homozygous for the dominant allele is (1.) 0.7 (2.) 0.21 (3.) 0.42 (4.) 0.49 (5.)
0.09
2. In a certain African tribe, 4% of the population is born with a severe form of
sickle cell anemia. What percentage of the tribe enjoys the selective advantage
of the sickle-cell gene by being more resistant to malaria than individuals who
are homozygous for "normal" hemoglobin? (1.) 4% (2.) 16% (3.) 20% (4.) 32%
(5.) 80%
3. Most of the genetic variation observed in large natural populations arises
from (1.) new mutations (2.) migration of individuals into and out of the
population (3.) recombination due to sexual reproduction (4.) genetic drift (5.)
differential predation upon members of the population
4. The most important kind of selection acting upon a well-adapted population
in a relative constant environment is (1.) directional selection (2.) stabilizing
selection (3.) disruptive selection
5. According to the Hardy-Weinberg Law, in the absence of natural selection
and mutation, and if the population experiences no migration, is very large, and
has random mating, which of the following statements is most correct? (1.)
Evolution of the population will continue at a normal rate. (2.) The makeup of
the population's gene pool will remain virtually the same indefinitely. (3.) The
makeup of the population's gene pool will change rapidly in a predictable
manner. (4.) Homozygosity will slowly increase in the population. (5.) The
dominant genes in the population's gene pool will slowly increase in frequency
while recessive alleles will decrease.
6. Suppose a characteristic of a species varies gradually from one end of the
species range to the other geographical end of this range. This would be an
example of (1.) polymorphism (2.) polyploidy (3.) genetic drift (4.) a cline
7. The process in which a population moves into a relatively unexploited
environment and then undergoes rapid evolutionary divergence to produce
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many separate species is called (1.) adaptive radiation (2.) convergence (3.)
phylogeny (4.) disruptive evolution (5.) punctuated equilibrium
8. Convergent evolution could cause a taxonomist (a student of classification)
to assume mistakenly that (1.) two unrelated species are closely related (2.) two
closely related species are unrelated (3.) members of different subpopulations
of the same species are unrelated
The terms below deal with speciation. For questions 9 through 12, match the
appropriate term from the list below to the sentences.
Choices
(1.) sympatric speciation
(2.) allopatric speciation
(3.) reproductive isolation
(4.) geographical isolation
(5.) genetic drift
9. Two plant species can often hybridize. The hybrid progeny may become selffertile through polyploidy, giving rise to a distinct new species.
10. By chance an allele may be eliminated from a population's gene pool.
11. Two large populations once exchanged genes via sexual reproduction. Now
if they hybridize, the progeny are infertile.
12. A large population of animals is split in two by a physical barrier. The gene
pools of the two resulting populations then diverge until each population
becomes a separate species.
13. If the frequency of two alleles in the population A and a is 80 percent and
20 percent, respectively, what will be the frequency of heterozygote individuals
in the population? (1.) 0.16 (2.) 0.32 (3.) 0.64 (4.) 0.40 (5.) 0.80
14. The idea that acquired characteristics are transmitted is most closely
associated with (1.) Darwin (2.) Wallace (3.) DeVries (4.) Mendel (5.) Lamarck
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15. Red-haired persons tend to sunburn more easily than persons with dark
brown hair. This exemplifies Darwin's assumption that (1.) some phenotypes
are selectively neutral (2.) different phenotypes have different fitnesses (3.) the
environment is a constant factor in selection (4.) fitness is inherited
16. The example in question # 15 above also illustrates that (1.) a given trait
may affect an organism in several different ways (2.) the fitness of a population
increases (3.) the importance of a trait depends upon the environment (4.) none
of these
17. The change of the coloration of the peppered moths is an example of
verifying the Darwinian theory by (1.) fossil record observations (2.)
mathematical models (3.) experimentation (4.) none of these
18. Which is NOT an assumption of the Hardy-Weinberg rule? (1.) random
mating (2.) no selection (3.) no mutations (4.) large population size (5.)
migration
19. If there are two alleles for the same gene locus (1.) the more fit will drive
the other to permanent extinction (2.) a proportional balance will develop based
on their ratios of mutation and selection (3.) they will occur in a 1:1 ratio (4.)
none of these
20. What is the founder principle (effect)? (1.) The principle that evolution is
primarily adaptive. (2.) The principle that genetic drift is unpredictable. (3.)
The genetic drift that results when a few members of a large colony population
establish a new population in an isolated spot (4.) The theory that separate
populations begin with similar phenotypes and change markedly, but always
resemble each other.
21. Placentals and marsupials that look structurally alike are good examples of
(1.) convergent evolution (2.) mutations (3.) adaptive radiation (4.) mimicry
(5.) parallel evolution
22. Two different species live in nearly identical habitats. Over time they have
evolved markedly, becoming more similar. They have undergone (1.) genetic
drift (2.) parallel evolution (3.) convergent evolution (4.) none of these
23. Geographic isolation allows for the development of new species because
(1.) individuals from separate populations are infertile (2.) it takes a long time
for barriers to develop (3.) the environment of the separated population differ
enough to select alleles differently (4.) none of these
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24. Geographical isolation is a prime cause of (1.) species extinction (2.)
speciation (3.) genetic drift (4.) infertility
25. As ancient cells became more crowded in the "primordial soup", the first
major competition was probably for (1.) sunlight (2.) oxygen (3.) organic
molecules (4.) water (5.) sexual partners
26. The first true organisms on earth probably depended entirely on
fermentation for the production of ATP, because aerobic respiration (1.) occurs
in eukaryotes, but the earliest organisms were prokaryotes (2.) could not occur
until the evolution of water-based photosynthesis had given rise to atmospheric
oxygen (3.) could only oxidize carbohydrates, while the earliest nutrients were
mostly of other types (4.) occurs only in animals, but the earliest organisms
were plants (5.) could not arise until after the evolution of a DNA-based genetic
control system
27. Which one of the following statements is FALSE? (1.) The earliest living
cells were heterotrophic. (2.) If we could examine some of the earliest cells
microscopically, we would classify them in the kingdom Monera. (3.) The
earth's primitive atmosphere was probably an oxidizing one, but the metabolic
activity of early organisms converted it into a reducing one. (4.) Coacervate
droplets have a marked tendency to incorporate various substances from the
surrounding medium. (5.) Many scientists believe that the mitochondria
evolved from bacteria.
28. The idea that mutations are the source of variations was first proposed by
(1.) Weismann (2.) Mendel (3.) Fox (4.) Miller (5.) DeVries (6.) Darwin (7.)
Lamarck
29. Which is a basic assumption of the heterotroph hypothesis? (1.) More
complex organisms appeared before less complex organisms. (2.) Living
organisms did not appear until there was oxygen in the atmosphere. (3.) Large
autotrophic organisms appeared before small photosynthesizing organisms. (4.)
Autotrophic activity added molecular oxygen to the environment.
30. Weismann's experiments with mice produced results that helped to (1.)
support Darwin's assumption of a struggle for survival (2.) disprove Lamarck's
theory (3.) disprove the concepts put forth by DeVries (4.) support the theories
of Miller and Fox
Questions 31 through 40 will be scored at a rate of one point per correct
response.
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The following listing of events in statements 31 through 35 relate to the
heterotroph hypothesis and early evolution. Place the number one before the
earliest event, two before the next event in the sequence, etc...
31. Polymerization of small organic molecules.
32. Great rains to form the ancient oceans.
33. Formation of the early earth and its atmosphere.
34. Abiotic synthesis of small organic molecules.
35. Formation of molecular aggregates and primitive cells.
Sequence the events indicated in statements 36 through 40. These statements
also relate to the heterotroph hypothesis and early evolution. Place the number
one before the earliest event, two before the next event in the sequence, etc...
36. Increasing oxygen levels in the atmosphere.
37. Evolution of many biochemical pathways and complex life activities in first
prokaryotic cells.
38. Reproduction and evolution of a genetic control system in primitive cells.
39. Evolution of photosynthesis.
40. Eukaryotic cell.
Use the following information to assist you in answering questions 41 through
43 below.
The following refer to the following events. In the year 2468, 2 male space
colonists and 3 female space colonists settle on an uninhabited Earth-like planet
in the Andromeda galaxy. The colonists and their offspring mate randomly for
many generations. All 5 of the original colonists had free ear lobes, and 2 were
heterozygous. The allele for free ear lobes is dominant over attached ear lobes.
41. Assuming the Hardy-Weinberg equilibrium applies on this planet, about
how many people will have attached ear lobes when the planet's population
reaches 10,000 people? (1.) 0 (2.) 400 (3.) 800 (4.) 1000 (5.) 10,000
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42. If 2 of the original colonists died before they produced offspring the ratios
of the genotypes could be quite different in the following generations. This is
an example of: (1.) diploidy (2.) gene flow (3.) genetic drift (4.) artificial
selection (5.) stabilizing selection
43. After many generations, the population on this planet had an unusually high
frequency for the incidence of colorblindness. This is most likely due to: (1.)
founder effect (2.) sexual selection (3.) coadapted genes (4.) introgression (5.)
polyploidy
44. The wings of birds and butterflies are _________ structures.
(1.) homologous (2.) complimentary (3.) analogous (4.) allopatric
45. Charles Darwin and _________ proposed the theory of natural selection.
(1.) Wil Farrell (2.) Charles Lyell (3.) Alfred Wallace (4.) William Smith
46. One prediction of evolutionary theory is
(1.) mammals should appear in the fossil record after reptiles (2.) humans
evolved from monkeys
(3.) features acquired during an organism's lifetime are inheritable (4.) species
are fixed and immutable
47. Who is the author of the 'Theory of inheritance of acquired characteristics'?
(1.) Charles Darwin (2.) Jean Baptiste de Lamarck (3.) Alfred Wallace (4.)
George Mendel
48. The idea that evolution occurs rapidly giving rise to new species in few
thousand years is the
basis of ______________________ concept. (1.) specialization (2.) phyletic
gradualism
(3.) rapid counterbalance (4.) punctuated equilibrium
49. All of the following statements concerning the theory of natural selection
are true except:
(1.) Organisms produce far more offspring than are required for replacement.
(2.) The individuals in a population show variability in survivability and in
their ability to cope with environmental stress.
(3.) The number of offspring that survive to reproduce varies amongst
individuals.
(4.) The bodies of organisms in a population change by use and disuse, and the
changes are inherited by the next generation.
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(5.) Some of the variation in adaptation is the result of genetic differences that
may be passed on to the next generation.
Essays
1. Describe the process of speciation. Include in your discussion the factors
that may contribute to the maintenance of genetic isolation. Include in your
discussion the concepts of introgression, polyploidy, and at least one
prezygotic and one postzygotic isolating mechanism. Also explain how
geographic isolation may lead to allopatric speciation. (18 pts.)
Choose either essay two or three please. (18 pts.)
2. Do the following with reference to the Hardy-Weinberg model.
a. Indicate the conditions under which allele frequencies (p and Q) remain
constant from one generation to the next. (at least four of them) (8 pts.)
b. Calculate, showing all work, the frequencies of the alleles and frequencies
of all the possible genotypes in a population of 100,000 rabbits of which 4,000
are white and 96,000 are agouti. (In rabbits the white color is due to a
recessive allele, w, and agouti is due to a dominant allele, W.)
I will NOT search for your work, specifically label the dominant and recessive
alleles, and the heterozygous dominant, and homozygous dominant and
recessive individuals. (10 pts.)
3. Evolution is one of the unifying concepts of modern biology. Explain
the mechanisms that lead to evolutionary change. Describe how
scientists use each of the following as evidence for evolution:
1) Bacterial resistance to antibiotics
2) Comparative biochemistry
3) The fossil record
4. In a laboratory population of diploid, sexually reproducing organisms a certain
trait is determined by a single autosomal gene and is expressed as two phenotypes. A
new population was created by crossing 51 pure-breeding (homozygous) dominant
individuals with 49 pure breeding (homozygous) recessive individuals. After four
generations, the following results were obtained.
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NUMBER OF INDIVIDUALS
Generation
1
2
3
4
5
Dominant
51
280
240
300
360
Recessive
49
0
80
100
120
Total
100
280
320
400
480
a) Identify an organism that might have been used to perform this experiment, and
explain why this organism is a good choice for conducting this experiment.
b) On the basis of the data, propose a hypothesis that explains the change in the
phenotype frequency between generation 1 and generation 3.
c) Is there evidence indicating whether or not this population is in
Hardy-Weinberg equilibrium? Explain
answers
1.) 4
2.) 4
3.) 3
4.) 2
5.) 2
6.) 4
7.) 1
8.) 1
9.) 1
10.) 5
11.) 3
12.) 2
13.) 2
14.) 5
15.) 2
16.) 3
17.) 4
18.) 5
19.) 2
20.) 3
21.) 5
22.) 3
23.) 3
24.) 2
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25.) 3
26.) 2
27.) 3
28.) 5
29.) 4
30.) 2
31.) 4
32.) 2
33.) 1
34.) 3
35.) 5
36.) 4
37.) 2
38.) 1
39.) 3
40.) 5
41.) (2) To do this question, you have to assess the allelic makeup of the 5
colonists. Three of them would be FF
and two of them would be Ff based on the information. Therefore if the
makeup of the five colonists is
FF, FF, FF, Ff, and Ff. With that in mind, the gene frequency for the dominant
allele big F is 8/10 or .8
and little F is .2 That means the percentage of homozygous recessives in the
population, those with attached
ear lobes is q2=.04 so the number of attached ear lobes would be .04 X 10,000
ppl or 400 ppl.
42. 3 Genetic drift is a random change in genetic frequencies which is greater
in tiny populations. This would
also be a classic founder effect.
43. 1 This population having started from five colonists probably had
significantly different genes than the original
population they came from.
44.
45.
46.
47.
48.
1
3
1
2
4
9
49. 4
Essay Key
1. Student correctly addresses the idea of:




introgression (incorporation of the gene complex of one species into
another species)
polyploidy (a nondisjunction resulting in a complete additional
chromosome set)
prezygotic and postzygotic isolating mechanism examples (many
examples ... prezygotic could include temporal isolation and postzygotic
could
include formation of an embryo with an odd chromosome number
incapable of forming proper gametes)
relating geographic isolation to allopatric speciation (different
geographical areas may have different conditions resulting in different
selection pressures
selecting for different variations of a species)
2. State four of the conditions for Hardy-Weinberg to be true
a. infinitely large population, no gene flow, no mutation, random mating, no
natural selection
b. p2 = .04 (homozygous white) 4,000 rabbits
p = .2 (percentage of recessive white allele)
q = .8 (percentage of dominant agouti allele)
q2 = .64 (64,000 homozygous agouti rabbits)
2pq = .32 (32,000 heterozygous agouti rabbits)
3. a.) Antibiotics have selected against non-resistant varieties of bacteria,
while the resistant varieties have lived and been selected for.
b.) Organisms with more similar nucleic acids and proteins have more
similar evolutionary histories.
c.) Fossils show a record of organisms in the past. A slow change in the
fossils with many transitional forms as one moves upward
through the sedimentary rock strata supports the concept of gradualism,
while abrupt discontinuities in the fossil record are more
supportive of the concept of punctuated equilibrium.
4. a.) Organisms with short generation times, easy to raise, and those that
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produce large numbers of offspring with easily visible contrasting
characteristics would be ideal. Organisms fitting these criteria would include
mice, fruit flies, and peas.
b.) Generation one shows a cross between pure dominant and recessive
individuals, producing all heterozygous dominants in the second generation.
The third generation shows the classic results observed in a cross between two
hybrid individuals (a 3:1 dominant : recessive ratio).
c.) As the percentage of homozygous recessives in generation one was 49%
(49 out of a total of 100), in this case q=.7. In generation number 5,
120 out of the total of 480 were homozygous recessive, so q2= .25
(120/480) and q=.5, so the gene frequency has shifted and therefore
the population from the beginning to the end was not in Hardy-Weinberg
equilibrium.
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