GRE Biology Test Practice Book

G R A D U A T E R E C O R D E X A M I N A T I O N S ®
Biology Test
Practice Book
This practice book contains
one actual, full-length GRE® Biology Test
test-taking
strategies
Become familiar with
test structure and content
test instructions and answering procedures
Compare your practice test results with the performance of those who
took the test at a GRE administration.
This book is provided FREE with test registration by the Graduate Record Examinations Board.
www.ets.org/gre

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Note to Test Takers: Keep this practice book until you receive your score report.
This book contains important information about scoring.
Copyright © 2008 by Educational Testing Service. All rights reserved.
ETS, the ETS logos, LISTENING. LEARNING. LEADING., GRADUATE RECORD EXAMINATIONS,
®
and GRE are registered trademarks of Educational Testing Service (ETS) in the United States of America
and other countries throughout the world.

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The GRE Board recommends that scores on the
Subject Tests be considered in conjunction with
Table of Contents
other relevant information about applicants. Because
Purpose of the GRE Subject Tests ................... 3
numerous factors infl uence success in graduate
school, reliance on a single measure to predict
Development of the Subject Tests ................... 3
success is not advisable. Other indicators of compe-
Content of the Biology Test ............................ 4
tence typically include undergraduate transcripts
Preparing for a Subject Test ............................. 8
showing courses taken and grades earned, letters of
recommendation, and GRE General Test scores.
Test-Taking Strategies ...................................... 8
For information about the appropriate use of GRE
What Your Scores Mean .................................. 9
scores, see the GRE Guide to the Use of Scores at
Practice Biology Test ....................................... 13
ets.org/gre/stupubs.
Scoring Your Subject Test ............................... 65
Evaluating Your Performance ......................... 68
Development of the
Answer Sheet .................................................. 69
Subject Tests
Each new edition of a Subject Test is developed by
a committee of examiners composed of professors in
Purpose of the GRE
the subject who are on undergraduate and graduate
Subject Tests
faculties in different types of institutions and in
different regions of the United States and Canada.
The GRE Subject Tests are designed to help gradu-
In selecting members for each committee, the GRE
ate school admission committees and fellowship
Program seeks the advice of appropriate professional
sponsors assess the qualifi cations of applicants in
associations in the subject.
specifi c fi elds of study. The tests also provide you
The content and scope of each test are specifi ed
with an assessment of your own qualifi cations.
and reviewed periodically by the committee of
Scores on the tests are intended to indicate
examiners. Test questions are written by committee
knowledge of the subject matter emphasized in
members and by other university faculty members
many undergraduate programs as preparation for
who are subject-matter specialists. All questions
graduate study. Because past achievement is usually
proposed for the test are reviewed and revised by
a good indicator of future performance, the scores
the committee and subject-matter specialists at
are helpful in predicting success in graduate study.
ETS. The tests are assembled in accordance with
Because the tests are standardized, the test scores
the content specifi cations developed by the com-
permit comparison of students from different
mittee to ensure adequate coverage of the various
institutions with different undergraduate programs.
aspects of the fi eld and, at the same time, to prevent
For some Subject Tests, subscores are provided in
overemphasis on any single topic. The entire test
addition to the total score; these subscores indicate
is then reviewed and approved by the committee.
the strengths and weaknesses of your preparation,
and they may help you plan future studies.
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Subject-matter and measurement specialists
The maximum possible range for all Subject Test
on the ETS staff assist the committee, providing
total scores is from 200 to 990. The actual range
information and advice about methods of test con-
of scores for a particular Subject Test, however,
struction and helping to prepare the questions and
may be smaller. For Subject Tests that report sub-
assemble the test. In addition, each test question is
scores, the maximum possible range is 20 to 99;
reviewed to eliminate language, symbols, or content
however, the actual range of subscores for any
considered potentially offensive, inappropriate for
test or test edition may be smaller than 20 to 99.
major subgroups of the test-taking population, or
Subject Test score interpretive information is
likely to perpetuate any negative attitude that may be
provided in Interpreting Your GRE Scores, which
conveyed to these subgroups.
you will receive with your GRE score report. This
Because of the diversity of undergraduate cur-
publication is also available at ets.org/gre/stupubs.
ricula, it is not possible for a single test to cover all
the material you may have studied. The examiners,
Content of the Biology Test
therefore, select questions that test the basic knowl-
edge and skills most important for successful graduate
The GRE Biology examination is designed to evaluate
study in the particular fi eld. The committee keeps the
the following abilities and background of the student.
test up-to-date by regularly developing new editions
Knowledge of basic vocabulary and facts in
and revising existing editions. In this way, the test
several biological fi elds at the equivalent of
content remains current. In addition, curriculum
an upper-level course.
surveys are conducted periodically to ensure that
the content of a test refl ects what is currently being
Conceptual understanding of ideas, relation-
taught in the undergraduate curriculum.
ships, and processes
After a new edition of a Subject Test is fi rst
Understanding of basic scientifi c research,
administered, examinees’ responses to each test
procedures, and tools
question are analyzed in a variety of ways to deter-
Capacity to read, evaluate, and draw conclusions
mine whether each question functioned as expected.
from unfamiliar laboratory and fi eld studies
These analyses may reveal that a question is ambigu-
ous, requires knowledge beyond the scope of the test,
Understanding of the connections among
or is inappropriate for the total group or a particular
biological fi elds and between biological fi elds
subgroup of examinees taking the test. Such questions
and allied sciences
are not used in computing scores.
The test contains about 200 fi ve-choice questions,
Following this analysis, the new test edition is
a number of which are grouped in sets toward the
equated to an existing test edition. In the equating
end of the test and are based on descriptions of
process, statistical methods are used to assess the
laboratory and fi eld situations, diagrams, or experi-
diffi culty of the new test. Then scores are adjusted so
mental results.
that examinees who took a more diffi cult edition of
To cover the broad fi eld of the biological sciences,
the test are not penalized, and examinees who took
the subject matter on which the students are tested
an easier edition of the test do not have an advantage.
is organized into three major areas: cellular and
Variations in the number of questions in the differ-
molecular biology; organismal biology; and ecology
ent editions of the test are also taken into account
and evolution. Approximately equal weight is given
in this process.
to each of these three areas. In addition to the total
Scores on the Subject Tests are reported as three-
score, a subscore in each of these subareas is reported.
digit scaled scores with the third digit always zero.
4
BIOLOGY TEST
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The approximate distribution of questions by
6. Cytoskeleton, motility, and shape
content category is shown below. However, subject
Actin-based
systems
areas indicated by Arabic numerals may not contain
Microtubule-based
systems
equal numbers of questions.
Intermediate fi laments
Bacterial fl agella and movement
I. Cellular and Molecular Biology
(33-34%)
7. Cell cycle, growth, division, and regulation
Fundamentals of cellular biology, genetics, and
(including signal transduction)
molecular biology are addressed. Major topics in
8. Methods
cellular structure and function include metabolic
Microscopy (e.g., electron, light,
pathways and their regulation, membrane dynamics
fl
uorescence)
and cell surfaces, organelles, cytoskeleton, and cell
Separation (e.g., centrifugation, gel fi ltration,
cycle. Major areas in genetics and molecular biol-
PAGE, Fluorescence activated cell
ogy include chromatin and chromosomal structure,
sorting
(FACS))
genomic organization and maintenance, and the
Immunological (e.g., Western Blotting,
regulation of gene expression. The cellular basis of
immunohistochemistry,
immunofl uor-
immunity and the mechanisms of antigen-antibody
escence)
interactions are included. Distinctions between pro-
B. Genetics and Molecular Biology
(16-17%)
karyotic and eukaryotic cells are considered where
appropriate. Attention is also given to experimental
1. Genetic foundations
methodology.
Mendelian
inheritance
Pedigree
analysis
A. Cellular Structure and Function
(16-17%)
Prokaryotic genetics (transformation,
1. Biological compounds
transduction, and conjugation)
Macromolecular structure and bonding
Genetic
mapping
Abiotic origin of biological molecules
2. Chromatin and chromosomes
2. Enzyme activity, receptor binding, and regulation
Nucleosomes
3. Major metabolic pathways and regulation
Karyotypes
Respiration, fermentation, and photosynthesis
Chromosomal
aberrations
Synthesis and degradation of macromolecules
Polytene
chromosomes
Hormonal control and intracellular messengers
3. Genome sequence organization
4. Membrane dynamics and cell surfaces
Introns and exons
Transport, endocytosis, and exocytosis
Single-copy and repetitive DNA
Electrical potentials and transmitter
Transposable
elements
substances
4. Genome maintenance
Mechanisms of cell recognition, cell
DNA
replication
junctions, and plasmodesmata
DNA mutation and repair
Cell wall and extracellular matrix
5. Gene expression and regulation in
5. Organelles: structure, function, synthesis,
prokaryotes and eukaryotes: mechanisms
and targeting
The
operon
Nucleus, mitochondria, and plastids
Promoters and enhancers
Endoplasmic reticulum and ribosomes
Transcription
factors
Golgi apparatus and secretory vesicles
RNA and protein synthesis
Lysosomes, peroxisomes, and vacuoles
Processing and modifi cations of both
RNA and protein
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6. Gene expression and regulation: effects
3. Support and movement
Control of normal development
Support systems (external, internal,
Cancer and oncogenes
and hydrostatic)
7. Immunobiology
Movement systems (fl agellar, ciliary, and
Cellular basis of immunity
muscular)
Antibody diversity and synthesis
4. Integration and control mechanisms
Antigen-antibody
interactions
Nervous and endocrine systems
8. Bacteriophages, animal viruses, and
5. Behavior (communication, orientation,
plant viruses
learning, and instinct)
Viral genomes, replication, and assembly
6. Metabolic rates (temperature, body size,

Virus - host cell interactions
and activity)
9. Recombinant DNA methodology
B. Animal Reproduction and Development (6%)
Restriction
endonucleases
Blotting and hybridization
1. Reproductive structures
Restriction fragment length polymorphisms
2. Meiosis, gametogenesis, and fertilization
DNA cloning, sequencing, and analysis
3. Early development (e.g., polarity, cleavage,
Polymerase chain reaction
and gastrulation)
4. Developmental processes (e.g., induction,
II. Organismal Biology
(33-34%)
determination, differentiation, morpho-
The structure, physiology, behavior, and development
genesis, and metamorphosis)
of plants and animals are addressed. Topics covered
5. External control mechanisms
include nutrient procurement and processing, gas
(e.g., photoperiod)
exchange, internal transport, regulation of fl uids,
C. Plant Structure, Function, and Organization,
control mechanisms and effectors, and reproduction

with Emphasis on Flowering Plants
(7%)
in autotrophic and heterotrophic organisms. Exam-
ples of developmental phenomena range from fertil-
1. Organs, tissue systems, and tissues
ization through differentiation and morphogenesis.
2. Water transport, including absorption
Perceptions and responses to environmental stimuli
and transpiration
are examined as they pertain to both plants and
3. Phloem transport and storage
animals. Major distinguishing characteristics and
4. Mineral nutrition
phylogenetic relationships of selected groups from
5. Plant energetics (e.g., respiration and
the various kingdoms are also covered.
photosynthesis)
A. Animal Structure, Function,
D. Plant Reproduction, Growth, and
and
Organization
(10%)

Development, with Emphasis on
Flowering
Plants
(5%)
1. Exchange with environment
Nutrient, salt, and water exchange
1. Reproductive structures
Gas
exchange
2. Meiosis and sporogenesis
Energy
3. Gametogenesis and fertilization
2. Internal transport and exchange
4. Embryogeny and seed development
(circulatory, gastrovascular, and
5. Meristems, growth, morphogenesis, and
digestive systems)
differentiation
6. Control mechanisms (e.g., hormones,
photoperiod, and tropisms)
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BIOLOGY TEST
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E. Diversity of Life
(6%)
the molecular, individual, population, and higher
levels. Principles of ecology, genetics, and evolution
1. Archaea
are interrelated in many questions. Some questions
Morphology, physiology, and identifi cation
may require quantitative skills, including the inter-
2. Bacteria (including cyanobacteria)
pretation of simple mathematical models.
Morphology, physiology, pathology,
and identifi cation
A. Ecology
(16-17%)
3. Protista
1. Environment/organism interaction
Protozoa, other heterotrophic Protista
Biogeographic
patterns
(slime molds and Oomycota), and
Physiological
ecology
Autotrophic
Protista
Temporal patterns (e.g., seasonal fl uctuations)
Major distinguishing characteristics
2. Behavioral ecology
Phylogenetic
relationships
Habitat
selection
Importance (e.g. eutrophication, disease)
Mating
systems
4. Fungi
Social
systems
Distinctive features of major phyla
Resource
acquisition
(vegetative, asexual and sexual
3. Population Structure and Function
reproduction)
Population
dynamics/regulation
Generalized life cycles
Demography and life history strategies
Importance (e.g., decomposition,
4. Communities
biodegradation, antibiotics, and
Direct and indirect interspecifi c interactions
pathogenicity)
Community structure and diversity
Lichens
Change and succession
5. Animalia with emphasis on major phyla
5. Ecosystems
Major distinguishing characteristics
Productivity and energy fl ow
Phylogenetic
relationships
Chemical
cycling
6. Plantae with emphasis on major phyla
Alternation of generations
B. Evolution
(16-17%)
Major distinguishing characteristics
Phylogenetic
relationships
1. Genetic variability
Origins (mutations, linkage, recombination,
III. Ecology and Evolution
(33-34%)
and chromosomal alterations)
This section deals with the interactions of organ-
Levels (e.g., polymorphism and heritability)
isms and their environment, emphasizing biological
Spatial patterns (e.g., clines and ecotypes)
principles at levels above the individual. Ecologi-
Hardy-Weinberg
equilibrium
cal and evolutionary topics are given equal weight.
2. Evolutionary processes
Ecological questions range from physiological
Gene fl ow and genetic drift
adaptations to the functioning of ecosystems. Al-
Natural selection and its dynamics
though principles are emphasized, some questions
Levels of selection (e.g., individual
may consider applications to current environmental
and
group)
problems. Questions in evolution range from its
Trade-offs and genetic correlations
genetic foundations through evolutionary processes
to their consequences. Evolution is considered at
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PRACTICE BOOK

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3. Evolutionary consequences
Following are some general test-taking strategies
Fitness and adaptation
you may want to consider.
Speciation
Read the test directions carefully, and work
Systematics and phylogeny
as rapidly as you can without being careless.
Convergence, divergence, and extinction
For each question, choose the best answer
Coevolution
from the available options.
4. History of life
Origin of prokaryotic and eukaryotic cells
All questions are of equal value; do not waste
Fossil
record
time pondering individual questions you fi nd
Paleontology and paleoecology
extremely diffi cult or unfamiliar.
You may want to work through the test quite
Preparing for a
rapidly, fi rst answering only the questions
about which you feel confi dent, then going
Subject Test
back and answering questions that require
GRE Subject Test questions are designed to measure
more thought, and concluding with the most
skills and knowledge gained over a long period of
diffi cult questions if there is time.
time. Although you might increase your scores to
If you decide to change an answer, make sure
some extent through preparation a few weeks or
you completely erase it and fi ll in the oval
months before you take the test, last minute cramming
corresponding to your desired answer.
is unlikely to be of further help. The following infor-
Questions for which you mark no answer
mation may be helpful.
or more than one answer are not counted
A general review of your college courses is
in scoring.
probably the best preparation for the test.
Your score will be determined by subtracting
However, the test covers a broad range of
one-fourth the number of incorrect answers
subject matter, and no one is expected to be
from the number of correct answers. If you
familiar with the content of every question.
have some knowledge of a question and
Use this practice book to become familiar
are able to rule out one or more of the
with the types of questions in the GRE
answer choices as incorrect, your chances
Biology Test, paying special attention to the
of selecting the correct answer are improved,
directions. If you thoroughly understand the
and answering such questions will likely
directions before you take the test, you will
improve your score. It is unlikely that pure
have more time during the test to focus on
guessing will raise your score; it may lower
the questions themselves.
your score.
Record all answers on your answer sheet.
Test-Taking Strategies
Answers recorded in your test book will
not be counted.
The questions in the practice test in this book
Do not wait until the last fi ve minutes of
illustrate the types of multiple-choice questions in
a testing session to record answers on your
the test. When you take the actual test, you will
answer sheet.
mark your answers on a separate machine-scorable
answer sheet. Total testing time is two hours and
fi fty minutes; there are no separately timed sections.
8
BIOLOGY TEST
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What Your Scores Mean
Range of Raw Scores* Needed
to Earn Selected Scaled Score
Your raw score, that is—the number of questions
on Three Biology Test Editions
you answered correctly minus one-fourth of the
That Differ in Diffi culty
number you answered incorrectly—is converted to
the scaled score that is reported. This conversion
Raw Scores
Scaled Score
ensures that a scaled score reported for any edition
Form A
Form B
Form C
of a Subject Test is comparable to the same scaled
800
128-130
124-125
120-121
score earned on any other edition of the same test.
700
101-103
95-97
92-94
Thus, equal scaled scores on a particular Subject
600
74-76
67-69
64-66
Test indicate essentially equal levels of performance
regardless of the test edition taken. Test scores
500
47-49
39-41
37-39
should be compared only with other scores on the
Number of Questions Used to Compute Raw Score
same Subject Test. (For example, a 680 on the
199
198
200
Computer Science Test is not equivalent to a 680
on the Mathematics Test.)
*Raw Score = Number of correct answers minus one-fourth the
number of incorrect answers, rounded to the nearest integer.
Before taking the test, you may fi nd it useful
to know approximately what raw scores would be
required to obtain a certain scaled score. Several
For a particular test edition, there are many ways
factors infl uence the conversion of your raw score
to earn the same raw score. For example, on the
to your scaled score, such as the diffi culty of the test
edition listed above as “Form A,” a raw score of
edition and the number of test questions included
101 through 103 would earn a scaled score of 700.
in the computation of your raw score. Based on
Below are a few of the possible ways in which a
recent editions of the Biology Test, the following
scaled score of 700 could be earned on the edition:
table gives the range of raw scores associated with
selected scaled scores for three different test editions.
(Note that when the number of scored questions
for a given test is greater than the range of possible
Examples of Ways to Earn
scaled scores, it is likely that two or more raw scores
a Scaled Score of 700
will convert to the same scaled score.) The three
on the Edition Labeled as “Form A”
test editions in the table that follows were selected
Number of
to refl ect varying degrees of diffi culty. Examinees
Questions
should note that future test editions may be some-
Questions
Questions
Questions
Used to
what more or less diffi cult than those test editions
Raw
Answered
Answered
Not
Compute
Score
Correctly
Incorrectly
Answered
Raw Score
illustrated in the table.
101
101
0
98
199
101
111
39
49
199
101
120
78
1
199
103
103
0
96
199
103
112
37
50
199
103
122
75
2
199
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