GRE Subject Tests Overview | Biology, GRE Test Preparation Practice Exercises for Verbal, Antonyms, Analogies with Explanations, Analytical Writing, Quantitative

GRE Subject Tests Overview | Biology

The test consists of approximately 200 five-choice questions, a number of which are grouped in sets toward the end of the test and are based on descriptions of laboratory and field situations, diagrams, or experimental results.
The content of the test is organized into three major areas: cellular and molecular biology, organismal biology, and ecology and evolution. Approximately equal weight is given to each of these three areas. In addition to the total score, a subscore in each of these subfield areas is reported. Subject area subdivisions indicated by Arabic numerals may not contain equal numbers of questions.

The approximate distribution of questions by content category is shown below.

I. Cellular and Molecular Biology (33-34%)

Fundamentals of cellular biology, genetics, and molecular biology are addressed.
Major topics in cellular structure and function include metabolic pathways and their regulation, membrane dynamics and cell surfaces, organelles, cytoskeleton, and cell cycle.
Major areas in genetics and molecular biology include chromatin and chromosomal structure, genomic organization and maintenance, and the regulation of gene expression.
The cellular basis of immunity and the mechanisms of antigen-antibody interactions are included. Distinctions between prokaryotic and eukaryotic cells are considered where appropriate.
Attention is also given to experimental methodology.

A. Cellular Structure and Function (16-17%)

1. Biological compounds

Macromolecular structure and bonding
Abiotic origin of biological molecules

2. Enzyme activity, receptor binding, and regulation

3. Major metabolic pathways and regulation

Respiration, fermentation, and photosynthesis
Synthesis and degradation of macromolecules
Hormonal control and intracellular messengers

4. Membrane dynamics and cell surfaces

Transport, endocytosis, and exocytosis
Electrical potentials and transmitter substances
Mechanisms of cell recognition, cell junctions, and plasmodesmata
Cell wall and extracellular matrix

5. Organelles: structure, function, synthesis, and targeting

Nucleus, mitochondria, and plastids
Endoplasmic reticulum and ribosomes
Golgi apparatus and secretory vesicles
Lysosomes, peroxisomes, and vacuoles

6. Cytoskeleton, motility, and shape

Actin-based systems
Microtubule-based systems
Intermediate filaments
Bacterial flagella and movement

7. Cell cycle, growth, division, and regulation (including signal transduction)

8. Methods

Microscopy (e.g., electron, light, fluorescence)
Separation (e.g., centrifugation, gel filtration, PAGE, Fluorescence activated cell sorting (FACS))
Immunological (e.g., Western Blotting, immunohistochemistry, immunofluorescence)

B. Genetics and Molecular Biology (16-17%)

1. Genetic foundations

Mendelian inheritance
Pedigree analysis
Prokaryotic genetics (transformation, transduction, and conjugation)
Genetic mapping

2. Chromatin and chromosomes

Nucleosomes
Karyotypes
Chromosomal aberrations
Polytene chromosomes

3. Genome sequence organization

Introns and exons
Single-copy and repetitive DNA
Transposable elements

4. Genome maintenance

DNA replication
DNA mutation and repair

5. Gene expression and regulation in prokaryotes and eukaryotes: mechanisms

The operon
Promoters and enhancers
Transcription factors
RNA and protein synthesis
Processing and modifications of both RNA and protein

6. Gene expression and regulation: effects

Control of normal development
Cancer and oncogenes

7. Immunobiology

Cellular basis of immunity
Antibody diversity and synthesis
Antigen-antibody interactions

8. Bacteriophages, animal viruses, and plant viruses

Viral genomes, replication, and assembly
Virus - host cell interactions

9. Recombinant DNA methodology

Restriction endonucleases
Blotting and hybridization
Restriction fragment length polymorphisms
DNA cloning, sequencing, and analysis
Polymerase chain reaction

II. Organismal Biology (33-34%)

The structure, physiology, behavior, and development of plants and animals are addressed. Topics covered include nutrient procurement and processing, gas exchange, internal transport, regulation of fluids, control mechanisms and effectors, and reproduction in autotrophic and heterotrophic organisms. Examples of developmental phenomena range from fertilization through differentiation and morphogenesis. Perceptions and responses to environmental stimuli are examined as they pertain to both plants and animals. Major distinguishing characteristics and phylogenetic relationships of selected groups from the various kingdoms are also covered.

A. Animal Structure, Function, and Organization (10%)

1. Exchange with environment

Nutrient, salt, and water exchange
Gas exchange
Energy

2. Internal transport and exchange

(circulatory, gastrovascular, and digestive systems)

3. Support and movement

Support systems (external, internal, and hydrostatic)
Movement systems (flagellar, ciliary, and muscular)

4. Integration and control mechanisms

Nervous and endocrine systems

5. Behavior (communication, orientation, learning, and instinct)

6. Metabolic rates (temperature, body size, and activity)

B. Animal Reproduction and Development (6%)

1. Reproductive structures

2. Meiosis, gametogenesis, and fertilization

3. Early development (e.g., polarity, cleavage, and gastrulation)

4. Developmental processes (e.g., induction, determination, differentiation, morphogenesis, and metamorphosis)

5. External control mechanisms (e.g., photoperiod)

C. Plant Structure, Function, and Organization, with Emphasis on Flowering Plants (7%)

1. Organs, tissue systems, and tissues

2. Water transport, including absorption and transpiration

3. Phloem transport and storage

4. Mineral nutrition

5. Plant energetics (e.g., respiration and photosynthesis)

D. Plant Reproduction, Growth, and Development, with Emphasis on Flowering Plants (5%)

1. Reproductive structures

2. Meiosis and sporogenesis

3. Gametogenesis and fertilization

4. Embryogeny and seed development

5. Meristems, growth, morphogenesis, and differentiation

6. Control mechanisms (e.g., hormones, photoperiod, and tropisms)

E. Diversity of Life (6%)

1. Archaea

Morphology, physiology, and identification

2. Bacteria (including cyanobacteria)

Morphology, physiology, pathology, and identification

3. Protista

Protozoa, other heterotrophic Protista (slime molds and Oomycota), and Autotrophic Protista
Major distinguishing characteristics
Phylogenetic relationships
Importance (e.g. eutrophication, disease)

4. Fungi

Distinctive features of major phyla (vegetative, asexual and sexual reproduction)
Generalized life cycles
Importance (e.g., decomposition, biodegradation, antibiotics, and pathogenicity)
Lichens

5. Animalia with emphasis on major phyla

Major distinguishing characteristics
Phylogenetic relationships

6. Plantae with emphasis on major phyla

Alternation of generations
Major distinguishing characteristics
Phylogenetic relationships

III. Ecology and Evolution (33-34%)

This section deals with the interactions of organisms and their environment, emphasizing biological principles at levels above the individual. Ecological and evolutionary topics are given equal weight. Ecological questions range from physiological adaptations to the functioning of ecosystems. Although principles are emphasized, some questions may consider applications to current environmental problems. Questions in evolution range from its genetic foundations through evolutionary processes to their consequences. Evolution is considered at the molecular, individual, population, and higher levels. Principles of ecology, genetics, and evolution are interrelated in many questions. Some questions may require quantitative skills, including the interpretation of simple mathematical models.

A. Ecology (16-17%)

1. Environment/organism interaction