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Biology

Index

BiologyIndex
  1. Preface
  2. Unit 1. The Chemistry of Life
    1. 1 The Study of Life
      1. Introduction
      2. 1.1 The Science of Biology
      3. 1.2 Themes and Concepts of Biology
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    2. 2 The Chemical Foundation of Life
      1. Introduction
      2. 2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
      3. 2.2 Water
      4. 2.3 Carbon
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 3 Biological Macromolecules
      1. Introduction
      2. 3.1 Synthesis of Biological Macromolecules
      3. 3.2 Carbohydrates
      4. 3.3 Lipids
      5. 3.4 Proteins
      6. 3.5 Nucleic Acids
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
  3. Unit 2. The Cell
    1. 4 Cell Structure
      1. Introduction
      2. 4.1 Studying Cells
      3. 4.2 Prokaryotic Cells
      4. 4.3 Eukaryotic Cells
      5. 4.4 The Endomembrane System and Proteins
      6. 4.5 The Cytoskeleton
      7. 4.6 Connections between Cells and Cellular Activities
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    2. 5 Structure and Function of Plasma Membranes
      1. Introduction
      2. 5.1 Components and Structure
      3. 5.2 Passive Transport
      4. 5.3 Active Transport
      5. 5.4 Bulk Transport
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 6 Metabolism
      1. Introduction
      2. 6.1 Energy and Metabolism
      3. 6.2 Potential, Kinetic, Free, and Activation Energy
      4. 6.3 The Laws of Thermodynamics
      5. 6.4 ATP: Adenosine Triphosphate
      6. 6.5 Enzymes
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    4. 7 Cellular Respiration
      1. Introduction
      2. 7.1 Energy in Living Systems
      3. 7.2 Glycolysis
      4. 7.3 Oxidation of Pyruvate and the Citric Acid Cycle
      5. 7.4 Oxidative Phosphorylation
      6. 7.5 Metabolism without Oxygen
      7. 7.6 Connections of Carbohydrate, Protein, and Lipid Metabolic Pathways
      8. 7.7 Regulation of Cellular Respiration
      9. Key Terms
      10. Chapter Summary
      11. Visual Connection Questions
      12. Review Questions
      13. Critical Thinking Questions
    5. 8 Photosynthesis
      1. Introduction
      2. 8.1 Overview of Photosynthesis
      3. 8.2 The Light-Dependent Reactions of Photosynthesis
      4. 8.3 Using Light Energy to Make Organic Molecules
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    6. 9 Cell Communication
      1. Introduction
      2. 9.1 Signaling Molecules and Cellular Receptors
      3. 9.2 Propagation of the Signal
      4. 9.3 Response to the Signal
      5. 9.4 Signaling in Single-Celled Organisms
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    7. 10 Cell Reproduction
      1. Introduction
      2. 10.1 Cell Division
      3. 10.2 The Cell Cycle
      4. 10.3 Control of the Cell Cycle
      5. 10.4 Cancer and the Cell Cycle
      6. 10.5 Prokaryotic Cell Division
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
  4. Unit 3. Genetics
    1. 11 Meiosis and Sexual Reproduction
      1. Introduction
      2. 11.1 The Process of Meiosis
      3. 11.2 Sexual Reproduction
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    2. 12 Mendel's Experiments and Heredity
      1. Introduction
      2. 12.1 Mendel’s Experiments and the Laws of Probability
      3. 12.2 Characteristics and Traits
      4. 12.3 Laws of Inheritance
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 13 Modern Understandings of Inheritance
      1. Introduction
      2. 13.1 Chromosomal Theory and Genetic Linkage
      3. 13.2 Chromosomal Basis of Inherited Disorders
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    4. 14 DNA Structure and Function
      1. Introduction
      2. 14.1 Historical Basis of Modern Understanding
      3. 14.2 DNA Structure and Sequencing
      4. 14.3 Basics of DNA Replication
      5. 14.4 DNA Replication in Prokaryotes
      6. 14.5 DNA Replication in Eukaryotes
      7. 14.6 DNA Repair
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    5. 15 Genes and Proteins
      1. Introduction
      2. 15.1 The Genetic Code
      3. 15.2 Prokaryotic Transcription
      4. 15.3 Eukaryotic Transcription
      5. 15.4 RNA Processing in Eukaryotes
      6. 15.5 Ribosomes and Protein Synthesis
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    6. 16 Gene Expression
      1. Introduction
      2. 16.1 Regulation of Gene Expression
      3. 16.2 Prokaryotic Gene Regulation
      4. 16.3 Eukaryotic Epigenetic Gene Regulation
      5. 16.4 Eukaryotic Transcription Gene Regulation
      6. 16.5 Eukaryotic Post-transcriptional Gene Regulation
      7. 16.6 Eukaryotic Translational and Post-translational Gene Regulation
      8. 16.7 Cancer and Gene Regulation
      9. Key Terms
      10. Chapter Summary
      11. Visual Connection Questions
      12. Review Questions
      13. Critical Thinking Questions
    7. 17 Biotechnology and Genomics
      1. Introduction
      2. 17.1 Biotechnology
      3. 17.2 Mapping Genomes
      4. 17.3 Whole-Genome Sequencing
      5. 17.4 Applying Genomics
      6. 17.5 Genomics and Proteomics
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
  5. Unit 4. Evolutionary Processes
    1. 18 Evolution and the Origin of Species
      1. Introduction
      2. 18.1 Understanding Evolution
      3. 18.2 Formation of New Species
      4. 18.3 Reconnection and Rates of Speciation
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    2. 19 The Evolution of Populations
      1. Introduction
      2. 19.1 Population Evolution
      3. 19.2 Population Genetics
      4. 19.3 Adaptive Evolution
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 20 Phylogenies and the History of Life
      1. Introduction
      2. 20.1 Organizing Life on Earth
      3. 20.2 Determining Evolutionary Relationships
      4. 20.3 Perspectives on the Phylogenetic Tree
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  6. Unit 5. Biological Diversity
    1. 21 Viruses
      1. Introduction
      2. 21.1 Viral Evolution, Morphology, and Classification
      3. 21.2 Virus Infections and Hosts
      4. 21.3 Prevention and Treatment of Viral Infections
      5. 21.4 Other Acellular Entities: Prions and Viroids
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    2. 22 Prokaryotes: Bacteria and Archaea
      1. Introduction
      2. 22.1 Prokaryotic Diversity
      3. 22.2 Structure of Prokaryotes
      4. 22.3 Prokaryotic Metabolism
      5. 22.4 Bacterial Diseases in Humans
      6. 22.5 Beneficial Prokaryotes
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    3. 23 Protists
      1. Introduction
      2. 23.1 Eukaryotic Origins
      3. 23.2 Characteristics of Protists
      4. 23.3 Groups of Protists
      5. 23.4 Ecology of Protists
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    4. 24 Fungi
      1. Introduction
      2. 24.1 Characteristics of Fungi
      3. 24.2 Classifications of Fungi
      4. 24.3 Ecology of Fungi
      5. 24.4 Fungal Parasites and Pathogens
      6. 24.5 Importance of Fungi in Human Life
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    5. 25 Seedless Plants
      1. Introduction
      2. 25.1 Early Plant Life
      3. 25.2 Green Algae: Precursors of Land Plants
      4. 25.3 Bryophytes
      5. 25.4 Seedless Vascular Plants
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    6. 26 Seed Plants
      1. Introduction
      2. 26.1 Evolution of Seed Plants
      3. 26.2 Gymnosperms
      4. 26.3 Angiosperms
      5. 26.4 The Role of Seed Plants
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    7. 27 Introduction to Animal Diversity
      1. Introduction
      2. 27.1 Features of the Animal Kingdom
      3. 27.2 Features Used to Classify Animals
      4. 27.3 Animal Phylogeny
      5. 27.4 The Evolutionary History of the Animal Kingdom
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    8. 28 Invertebrates
      1. Introduction
      2. 28.1 Phylum Porifera
      3. 28.2 Phylum Cnidaria
      4. 28.3 Superphylum Lophotrochozoa
      5. 28.4 Superphylum Ecdysozoa
      6. 28.5 Superphylum Deuterostomia
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    9. 29 Vertebrates
      1. Introduction
      2. 29.1 Chordates
      3. 29.2 Fishes
      4. 29.3 Amphibians
      5. 29.4 Reptiles
      6. 29.5 Birds
      7. 29.6 Mammals
      8. 29.7 The Evolution of Primates
      9. Key Terms
      10. Chapter Summary
      11. Visual Connection Questions
      12. Review Questions
      13. Critical Thinking Questions
  7. Unit 6. Plant Structure and Function
    1. 30 Plant Form and Physiology
      1. Introduction
      2. 30.1 The Plant Body
      3. 30.2 Stems
      4. 30.3 Roots
      5. 30.4 Leaves
      6. 30.5 Transport of Water and Solutes in Plants
      7. 30.6 Plant Sensory Systems and Responses
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    2. 31 Soil and Plant Nutrition
      1. Introduction
      2. 31.1 Nutritional Requirements of Plants
      3. 31.2 The Soil
      4. 31.3 Nutritional Adaptations of Plants
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 32 Plant Reproduction
      1. Introduction
      2. 32.1 Reproductive Development and Structure
      3. 32.2 Pollination and Fertilization
      4. 32.3 Asexual Reproduction
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  8. Unit 7. Animal Structure and Function
    1. 33 The Animal Body: Basic Form and Function
      1. Introduction
      2. 33.1 Animal Form and Function
      3. 33.2 Animal Primary Tissues
      4. 33.3 Homeostasis
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    2. 34 Animal Nutrition and the Digestive System
      1. Introduction
      2. 34.1 Digestive Systems
      3. 34.2 Nutrition and Energy Production
      4. 34.3 Digestive System Processes
      5. 34.4 Digestive System Regulation
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 35 The Nervous System
      1. Introduction
      2. 35.1 Neurons and Glial Cells
      3. 35.2 How Neurons Communicate
      4. 35.3 The Central Nervous System
      5. 35.4 The Peripheral Nervous System
      6. 35.5 Nervous System Disorders
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    4. 36 Sensory Systems
      1. Introduction
      2. 36.1 Sensory Processes
      3. 36.2 Somatosensation
      4. 36.3 Taste and Smell
      5. 36.4 Hearing and Vestibular Sensation
      6. 36.5 Vision
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    5. 37 The Endocrine System
      1. Introduction
      2. 37.1 Types of Hormones
      3. 37.2 How Hormones Work
      4. 37.3 Regulation of Body Processes
      5. 37.4 Regulation of Hormone Production
      6. 37.5 Endocrine Glands
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    6. 38 The Musculoskeletal System
      1. Introduction
      2. 38.1 Types of Skeletal Systems
      3. 38.2 Bone
      4. 38.3 Joints and Skeletal Movement
      5. 38.4 Muscle Contraction and Locomotion
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    7. 39 The Respiratory System
      1. Introduction
      2. 39.1 Systems of Gas Exchange
      3. 39.2 Gas Exchange across Respiratory Surfaces
      4. 39.3 Breathing
      5. 39.4 Transport of Gases in Human Bodily Fluids
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    8. 40 The Circulatory System
      1. Introduction
      2. 40.1 Overview of the Circulatory System
      3. 40.2 Components of the Blood
      4. 40.3 Mammalian Heart and Blood Vessels
      5. 40.4 Blood Flow and Blood Pressure Regulation
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    9. 41 Osmotic Regulation and Excretion
      1. Introduction
      2. 41.1 Osmoregulation and Osmotic Balance
      3. 41.2 The Kidneys and Osmoregulatory Organs
      4. 41.3 Excretion Systems
      5. 41.4 Nitrogenous Wastes
      6. 41.5 Hormonal Control of Osmoregulatory Functions
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    10. 42 The Immune System
      1. Introduction
      2. 42.1 Innate Immune Response
      3. 42.2 Adaptive Immune Response
      4. 42.3 Antibodies
      5. 42.4 Disruptions in the Immune System
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    11. 43 Animal Reproduction and Development
      1. Introduction
      2. 43.1 Reproduction Methods
      3. 43.2 Fertilization
      4. 43.3 Human Reproductive Anatomy and Gametogenesis
      5. 43.4 Hormonal Control of Human Reproduction
      6. 43.5 Human Pregnancy and Birth
      7. 43.6 Fertilization and Early Embryonic Development
      8. 43.7 Organogenesis and Vertebrate Formation
      9. Key Terms
      10. Chapter Summary
      11. Visual Connection Questions
      12. Review Questions
      13. Critical Thinking Questions
  9. Unit 8. Ecology
    1. 44 Ecology and the Biosphere
      1. Introduction
      2. 44.1 The Scope of Ecology
      3. 44.2 Biogeography
      4. 44.3 Terrestrial Biomes
      5. 44.4 Aquatic Biomes
      6. 44.5 Climate and the Effects of Global Climate Change
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    2. 45 Population and Community Ecology
      1. Introduction
      2. 45.1 Population Demography
      3. 45.2 Life Histories and Natural Selection
      4. 45.3 Environmental Limits to Population Growth
      5. 45.4 Population Dynamics and Regulation
      6. 45.5 Human Population Growth
      7. 45.6 Community Ecology
      8. 45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
      9. Key Terms
      10. Chapter Summary
      11. Visual Connection Questions
      12. Review Questions
      13. Critical Thinking Questions
    3. 46 Ecosystems
      1. Introduction
      2. 46.1 Ecology of Ecosystems
      3. 46.2 Energy Flow through Ecosystems
      4. 46.3 Biogeochemical Cycles
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    4. 47 Conservation Biology and Biodiversity
      1. Introduction
      2. 47.1 The Biodiversity Crisis
      3. 47.2 The Importance of Biodiversity to Human Life
      4. 47.3 Threats to Biodiversity
      5. 47.4 Preserving Biodiversity
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
  10. A | The Periodic Table of Elements
  11. B | Geological Time
  12. C | Measurements and the Metric System
  13. Index
Symbols
3' UTR16.5 Eukaryotic Post-transcriptional Gene Regulation
40S ribosomal subunit16.6 Eukaryotic Translational and Post-translational Gene Regulation
5' cap16.5 Eukaryotic Post-transcriptional Gene Regulation
5' UTR16.5 Eukaryotic Post-transcriptional Gene Regulation
60S ribosomal subunit16.6 Eukaryotic Translational and Post-translational Gene Regulation
7-methylguanosine cap15.4 RNA Processing in Eukaryotes
α-helix3.4 Proteins
β-pleated sheet3.4 Proteins
A
A horizon31.2 The Soil
Abduction38.3 Joints and Skeletal Movement
abiotic44.1 The Scope of Ecology
aboveground biomass44.2 Biogeography
abscisic acid30.6 Plant Sensory Systems and Responses
abscission30.6 Plant Sensory Systems and Responses
absorption spectrum8.2 The Light-Dependent Reactions of Photosynthesis
abstract1.1 The Science of Biology
abyssal zone44.4 Aquatic Biomes
Acanthostega29.3 Amphibians
Accessory fruits32.2 Pollination and Fertilization
acclimatization33.3 Homeostasis
acellular21.1 Viral Evolution, Morphology, and Classification
acetyl CoA7.3 Oxidation of Pyruvate and the Citric Acid Cycle
acetylcholine35.4 The Peripheral Nervous System
acetylcholinesterase38.4 Muscle Contraction and Locomotion
acid2.2 Water
Acid rain46.3 Biogeochemical Cycles
acoelomates27.2 Features Used to Classify Animals
acromegaly37.3 Regulation of Body Processes
acrosomal reactions43.6 Fertilization and Early Embryonic Development
Actin38.4 Muscle Contraction and Locomotion
Actinopterygii29.2 Fishes
action potential35.2 How Neurons Communicate
activation energy6.2 Potential, Kinetic, Free, and Activation Energy
activators16.2 Prokaryotic Gene Regulation
active site6.5 Enzymes
Active transport5.3 Active Transport
acute disease21.2 Virus Infections and Hosts
adaptation18.1 Understanding Evolution
adaptive evolution19.3 Adaptive Evolution
Adaptive immunity42.2 Adaptive Immune Response
adaptive radiation18.2 Formation of New Species, 47.1 The Biodiversity Crisis
Addison’s disease37.3 Regulation of Body Processes
Adduction38.3 Joints and Skeletal Movement
adenosine triphosphate6.4 ATP: Adenosine Triphosphate
adenylyl cyclase37.2 How Hormones Work
adhesion2.2 Water
adrenal cortex37.5 Endocrine Glands
adrenal glands37.5 Endocrine Glands
adrenal medulla37.5 Endocrine Glands
adrenocorticotropic hormone (ACTH)37.3 Regulation of Body Processes
Adventitious25.4 Seedless Vascular Plants
adventitious roots30.3 Roots
aerobic respiration7.2 Glycolysis
afferent arteriole41.2 The Kidneys and Osmoregulatory Organs
affinities42.3 Antibodies
Age structure45.5 Human Population Growth
aggregate fruit32.2 Pollination and Fertilization
Aggressive displays45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
aldosterone37.3 Regulation of Body Processes
aleurone32.2 Pollination and Fertilization
algal bloom44.4 Aquatic Biomes
alimentary canal34.1 Digestive Systems
aliphatic hydrocarbons2.3 Carbon
allantois29.4 Reptiles
allele frequency19.1 Population Evolution
alleles12.2 Characteristics and Traits
allergy42.4 Disruptions in the Immune System
Allopatric speciation18.2 Formation of New Species
allopolyploid18.2 Formation of New Species
allosteric inhibition6.5 Enzymes
alpha cells37.5 Endocrine Glands
alteration33.3 Homeostasis
alternation of generations11.2 Sexual Reproduction
alveolar P O 2 P O 2 39.2 Gas Exchange across Respiratory Surfaces
alveolar ducts39.1 Systems of Gas Exchange
alveolar sacs39.1 Systems of Gas Exchange
alveolar ventilation39.3 Breathing
alveoli39.1 Systems of Gas Exchange
Alzheimer’s disease35.5 Nervous System Disorders
amino acid-derived hormones37.1 Types of Hormones
Amino acids3.4 Proteins
aminoacyl tRNA synthetases15.5 Ribosomes and Protein Synthesis
aminopeptidase34.3 Digestive System Processes
ammonia41.4 Nitrogenous Wastes
ammonification22.3 Prokaryotic Metabolism
ammonotelic41.4 Nitrogenous Wastes
amnion29.4 Reptiles
amoebocytes28.1 Phylum Porifera
Amphiarthroses38.3 Joints and Skeletal Movement
Amphibia29.3 Amphibians
amphiphilic5.1 Components and Structure
ampullae of Lorenzini29.2 Fishes
amygdala35.3 The Central Nervous System
Amyloplasts30.6 Plant Sensory Systems and Responses
Anabolic6.1 Energy and Metabolism
anaerobic7.2 Glycolysis, 22.1 Prokaryotic Diversity
anaerobic cellular respiration7.5 Metabolism without Oxygen
analogy20.2 Determining Evolutionary Relationships
analytical model46.1 Ecology of Ecosystems
anaphase10.2 The Cell Cycle
Anapsids29.4 Reptiles
Anatomical dead space39.3 Breathing
androecium32.1 Reproductive Development and Structure
androgens37.3 Regulation of Body Processes
aneuploid13.2 Chromosomal Basis of Inherited Disorders
angina40.3 Mammalian Heart and Blood Vessels
Angiotensin converting enzyme (ACE)41.5 Hormonal Control of Osmoregulatory Functions
angiotensin I41.5 Hormonal Control of Osmoregulatory Functions
angiotensin II41.5 Hormonal Control of Osmoregulatory Functions
Angular movements38.3 Joints and Skeletal Movement
Anions2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Annelida28.3 Superphylum Lophotrochozoa
anoxic22.1 Prokaryotic Diversity
antenna proteins8.2 The Light-Dependent Reactions of Photosynthesis
anterior pituitary37.5 Endocrine Glands
anther26.3 Angiosperms
antheridium25.1 Early Plant Life
Anthophyta26.3 Angiosperms
Anthropoids29.7 The Evolution of Primates
anti-diuretic hormone (ADH)41.5 Hormonal Control of Osmoregulatory Functions
antibiotic22.4 Bacterial Diseases in Humans
antibiotic resistance17.1 Biotechnology
antibody42.3 Antibodies
anticodon15.4 RNA Processing in Eukaryotes
antidiuretic hormone (ADH)37.3 Regulation of Body Processes
antigen42.2 Adaptive Immune Response
antigen-presenting cell (APC)42.2 Adaptive Immune Response
antioxidant41.4 Nitrogenous Wastes
antipodal32.1 Reproductive Development and Structure
antiporter5.3 Active Transport
Anura29.3 Amphibians
anus34.1 Digestive Systems
aorta40.3 Mammalian Heart and Blood Vessels
apex consumers46.1 Ecology of Ecosystems
aphotic zone44.4 Aquatic Biomes
apical bud30.2 Stems
Apical meristems30.1 The Plant Body
Apocrine glands29.6 Mammals
Apoda29.3 Amphibians
apodemes33.1 Animal Form and Function
apomixis32.3 Asexual Reproduction
apoptosis9.3 Response to the Signal
aposematic coloration45.6 Community Ecology
appendicular skeleton38.1 Types of Skeletal Systems
applied science1.1 The Science of Biology
Appositional growth38.2 Bone
Aquaporins5.2 Passive Transport
arachnoid mater35.3 The Central Nervous System
arbuscular mycorrhiza24.3 Ecology of Fungi
arbuscular mycorrhizae24.2 Classifications of Fungi
Archaeopteryx29.5 Birds
archegonia25.1 Early Plant Life
archenteron28.5 Superphylum Deuterostomia
archosaurs29.4 Reptiles
arcuate arteries41.2 The Kidneys and Osmoregulatory Organs
aromatic hydrocarbons2.3 Carbon
Arteries40.3 Mammalian Heart and Blood Vessels
arterioles40.3 Mammalian Heart and Blood Vessels
Arthropoda28.4 Superphylum Ecdysozoa
articulation38.1 Types of Skeletal Systems, 38.3 Joints and Skeletal Movement
ascending limbs41.2 The Kidneys and Osmoregulatory Organs
ascocarp24.2 Classifications of Fungi
Ascomycota24.2 Classifications of Fungi
ascus24.2 Classifications of Fungi
Asexual reproduction43.1 Reproduction Methods
Assimilation46.2 Energy Flow through Ecosystems
assortative mating19.2 Population Genetics
Astrocytes35.1 Neurons and Glial Cells
Asymmetrical33.1 Animal Form and Function
asymptomatic infection21.2 Virus Infections and Hosts
Atherosclerosis40.3 Mammalian Heart and Blood Vessels
atom1.2 Themes and Concepts of Biology, 2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
atomic mass2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
atomic number2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
ATP6.4 ATP: Adenosine Triphosphate
atria40.1 Overview of the Circulatory System
atrial natriuretic peptide (ANP)37.5 Endocrine Glands
atrioventricular valve40.3 Mammalian Heart and Blood Vessels
attention deficit/hyperactivity disorder (ADHD)35.5 Nervous System Disorders
attenuating21.3 Prevention and Treatment of Viral Infections
Audition36.4 Hearing and Vestibular Sensation
auditory ossicles38.1 Types of Skeletal Systems
Australopithecus29.7 The Evolution of Primates
Autism spectrum disorder (ASD)35.5 Nervous System Disorders
autoantibodies42.4 Disruptions in the Immune System
Autocrine signals9.1 Signaling Molecules and Cellular Receptors
autoimmune response42.2 Adaptive Immune Response
Autoimmunity42.4 Disruptions in the Immune System
Autoinducers9.4 Signaling in Single-Celled Organisms
autonomic nervous system35.4 The Peripheral Nervous System
autopolyploidy18.2 Formation of New Species
autosomes12.2 Characteristics and Traits, 13.2 Chromosomal Basis of Inherited Disorders
Auxins30.6 Plant Sensory Systems and Responses
avidity42.3 Antibodies
axial skeleton38.1 Types of Skeletal Systems
axillary bud30.2 Stems
axon35.1 Neurons and Glial Cells
axon hillock35.1 Neurons and Glial Cells
axon terminals35.1 Neurons and Glial Cells
AZT21.2 Virus Infections and Hosts
B
B cells42.1 Innate Immune Response
B horizon31.2 The Soil
back mutations21.3 Prevention and Treatment of Viral Infections
Bacteriophages21.2 Virus Infections and Hosts
balanced chemical equation2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Ball-and-socket joints38.3 Joints and Skeletal Movement
Barcoding26.4 The Role of Seed Plants
bark30.2 Stems
Basal angiosperms26.3 Angiosperms
basal ganglia35.3 The Central Nervous System
basal metabolic rate (BMR)33.1 Animal Form and Function
basal nuclei35.3 The Central Nervous System
basal taxon20.1 Organizing Life on Earth
base2.2 Water
Basic science1.1 The Science of Biology
basidia24.2 Classifications of Fungi
basidiocarp24.2 Classifications of Fungi
Basidiomycota24.2 Classifications of Fungi
basidium24.2 Classifications of Fungi
basilar membrane36.4 Hearing and Vestibular Sensation
basophil42.1 Innate Immune Response
Batesian mimicry45.6 Community Ecology
bedrock31.2 The Soil
Behavior45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Behavioral biology45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Behavioral isolation18.2 Formation of New Species
benthic realm44.4 Aquatic Biomes
beta cells37.5 Endocrine Glands
bicarbonate buffer system39.4 Transport of Gases in Human Bodily Fluids
bicarbonate ions (HCO 3 − ) (HCO 3 − ) 39.4 Transport of Gases in Human Bodily Fluids
bicuspid valve40.3 Mammalian Heart and Blood Vessels
Bilateral symmetry27.2 Features Used to Classify Animals
Bile34.1 Digestive Systems
binary (prokaryotic) fission10.5 Prokaryotic Cell Division
binomial nomenclature20.1 Organizing Life on Earth
biochemistry1.2 Themes and Concepts of Biology
biodiversity47.1 The Biodiversity Crisis
Biodiversity hotspots47.1 The Biodiversity Crisis
bioenergetics6.1 Energy and Metabolism
biofilm22.1 Prokaryotic Diversity
biogeochemical cycle46.3 Biogeochemical Cycles
Biogeography44.2 Biogeography
biological carbon pump23.3 Groups of Protists
biological macromolecules3.1 Synthesis of Biological Macromolecules
Biological nitrogen fixation22.5 Beneficial Prokaryotes
biology1.1 The Science of Biology
bioluminescence23.3 Groups of Protists
Biomagnification46.2 Energy Flow through Ecosystems
biomarker17.5 Genomics and Proteomics
Biomass46.2 Energy Flow through Ecosystems
biomes44.2 Biogeography
bioremediation22.5 Beneficial Prokaryotes
biosphere1.2 Themes and Concepts of Biology
Biotechnology17.1 Biotechnology, 22.5 Beneficial Prokaryotes
biotic44.1 The Scope of Ecology
biotic potential, or rmax45.3 Environmental Limits to Population Growth
bipolar neurons36.3 Taste and Smell
biramous28.4 Superphylum Ecdysozoa
birth rate (B)45.3 Environmental Limits to Population Growth
Black Death22.4 Bacterial Diseases in Humans
blastocyst43.6 Fertilization and Early Embryonic Development
blastopore27.2 Features Used to Classify Animals
blastula27.1 Features of the Animal Kingdom
blending theory of inheritance12.1 Mendel’s Experiments and the Laws of Probability
Blood pressure (BP)40.4 Blood Flow and Blood Pressure Regulation
blood urea nitrogen41.4 Nitrogenous Wastes
blotting17.1 Biotechnology
body plan27.1 Features of the Animal Kingdom
bolus34.1 Digestive Systems
Bone38.2 Bone
Bone remodeling38.2 Bone
botany1.2 Themes and Concepts of Biology
bottleneck effect19.2 Population Genetics
botulism22.4 Bacterial Diseases in Humans
Bowman's capsule41.2 The Kidneys and Osmoregulatory Organs
brachiation29.7 The Evolution of Primates
brainstem35.3 The Central Nervous System
branch point20.1 Organizing Life on Earth
bronchi39.1 Systems of Gas Exchange
bronchioles39.1 Systems of Gas Exchange
Brumation29.4 Reptiles
budding21.2 Virus Infections and Hosts, 43.1 Reproduction Methods
Buffers2.2 Water
bulb30.2 Stems
bulbourethral gland43.3 Human Reproductive Anatomy and Gametogenesis
Bush meat47.3 Threats to Biodiversity
C
C horizon31.2 The Soil
CA-MRSA22.4 Bacterial Diseases in Humans
CAAT box15.3 Eukaryotic Transcription
caecilians29.3 Amphibians
Calcification38.2 Bone
calcitonin37.3 Regulation of Body Processes
calorie2.2 Water
Calvin cycle8.3 Using Light Energy to Make Organic Molecules
calyces41.2 The Kidneys and Osmoregulatory Organs
calyx26.3 Angiosperms
Cambrian explosion27.4 The Evolutionary History of the Animal Kingdom
camouflage45.6 Community Ecology
cAMP-dependent kinase (A-kinase)9.2 Propagation of the Signal
canaliculi33.2 Animal Primary Tissues
candela36.5 Vision
canopy44.3 Terrestrial Biomes
capillaries40.3 Mammalian Heart and Blood Vessels
capillary action2.2 Water
Capillary beds40.3 Mammalian Heart and Blood Vessels
capsid21.1 Viral Evolution, Morphology, and Classification
capsomeres21.1 Viral Evolution, Morphology, and Classification
capsule22.2 Structure of Prokaryotes, 25.3 Bryophytes
captaculae28.3 Superphylum Lophotrochozoa
carbaminohemoglobin39.4 Transport of Gases in Human Bodily Fluids
Carbohydrates3.2 Carbohydrates
carbon8.3 Using Light Energy to Make Organic Molecules
Carbonic anhydrase (CA)39.4 Transport of Gases in Human Bodily Fluids
carboxypeptidase34.3 Digestive System Processes
cardiac cycle40.3 Mammalian Heart and Blood Vessels
Cardiac muscle tissue38.4 Muscle Contraction and Locomotion
Cardiomyocytes40.3 Mammalian Heart and Blood Vessels
Carnivores34.1 Digestive Systems
carotenoids8.2 The Light-Dependent Reactions of Photosynthesis
carpel26.3 Angiosperms
carpus38.1 Types of Skeletal Systems
carrier protein5.2 Passive Transport
carrying capacity, or K45.3 Environmental Limits to Population Growth
Cartilage33.2 Animal Primary Tissues
Cartilaginous joints38.3 Joints and Skeletal Movement
Casineria29.4 Reptiles
Casparian strip30.3 Roots
catabolic6.1 Energy and Metabolism
catabolite activator protein (CAP)16.2 Prokaryotic Gene Regulation
Catarrhini29.7 The Evolution of Primates
Cations2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
caveolin5.4 Bulk Transport
cell1.2 Themes and Concepts of Biology
cell cycle10.1 Cell Division, 10.2 The Cell Cycle
cell cycle checkpoints10.3 Control of the Cell Cycle
cell necrosis21.2 Virus Infections and Hosts
cell plate10.2 The Cell Cycle
cell wall4.3 Eukaryotic Cells
cell-mediated immune response42.2 Adaptive Immune Response
Cell-surface receptors9.1 Signaling Molecules and Cellular Receptors
cellular cloning17.1 Biotechnology
Cellulose3.2 Carbohydrates
centimorgans (cM)13.1 Chromosomal Theory and Genetic Linkage
Central Dogma15.1 The Genetic Code
central vacuole4.3 Eukaryotic Cells
centrioles10.2 The Cell Cycle
centromere10.1 Cell Division
centrosome4.3 Eukaryotic Cells
cephalic phase34.4 Digestive System Regulation
Cephalochordata29.1 Chordates
cephalothorax28.4 Superphylum Ecdysozoa
cerebellum35.3 The Central Nervous System
cerebral cortex35.3 The Central Nervous System
cerebrospinal fluid (CSF)35.3 The Central Nervous System
channel44.4 Aquatic Biomes
Channel proteins5.2 Passive Transport
chaperones3.4 Proteins
Charophytes25.1 Early Plant Life
chelicerae28.4 Superphylum Ecdysozoa
chemical bonds2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
chemical diversity47.1 The Biodiversity Crisis
chemical energy6.2 Potential, Kinetic, Free, and Activation Energy
Chemical reactions2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
chemical reactivity2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
chemical synapses9.1 Signaling Molecules and Cellular Receptors
Chemiosmosis7.1 Energy in Living Systems
chemoautotrophs8.1 Overview of Photosynthesis, 46.2 Energy Flow through Ecosystems
Chemotrophs22.3 Prokaryotic Metabolism
chiasmata11.1 The Process of Meiosis
chitin3.2 Carbohydrates
chloride shift39.4 Transport of Gases in Human Bodily Fluids
chlorophyll4.3 Eukaryotic Cells
Chlorophyll a8.2 The Light-Dependent Reactions of Photosynthesis
chlorophyll b8.2 The Light-Dependent Reactions of Photosynthesis
chloroplast8.1 Overview of Photosynthesis
Chloroplasts4.3 Eukaryotic Cells
Choanocytes28.1 Phylum Porifera
cholecystokinin34.4 Digestive System Regulation
Chondrichthyes29.2 Fishes
chondrocytes33.2 Animal Primary Tissues
Chordata28.5 Superphylum Deuterostomia, 29.1 Chordates
chorion29.4 Reptiles
choroid plexus35.3 The Central Nervous System
chromatids10.1 Cell Division
chromatin4.3 Eukaryotic Cells
chromophore30.6 Plant Sensory Systems and Responses
Chromosomal Theory of Inheritance13.1 Chromosomal Theory and Genetic Linkage
chromosome inversion13.2 Chromosomal Basis of Inherited Disorders
Chromosomes4.3 Eukaryotic Cells, 10.1 Cell Division
chronic infections21.2 Virus Infections and Hosts
chylomicrons34.3 Digestive System Processes
chyme34.1 Digestive Systems
chymotrypsin34.3 Digestive System Processes
Chytridiomycetes24.2 Classifications of Fungi
chytridiomycosis47.3 Threats to Biodiversity
cilia4.5 The Cytoskeleton
cingulate gyrus35.3 The Central Nervous System
circadian36.5 Vision
Circumduction38.3 Joints and Skeletal Movement
cis-acting element16.4 Eukaryotic Transcription Gene Regulation
citric acid cycle7.3 Oxidation of Pyruvate and the Citric Acid Cycle
cladistics20.2 Determining Evolutionary Relationships
class20.1 Organizing Life on Earth
classical conditioning45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Clathrates44.5 Climate and the Effects of Global Climate Change
clathrin5.4 Bulk Transport
clavicles38.1 Types of Skeletal Systems
clay31.2 The Soil
cleavage27.1 Features of the Animal Kingdom, 27.2 Features Used to Classify Animals
cleavage furrow10.2 The Cell Cycle
Climate44.5 Climate and the Effects of Global Climate Change
climax community45.6 Community Ecology
cline19.2 Population Genetics
clitellum28.3 Superphylum Lophotrochozoa
clitoris43.3 Human Reproductive Anatomy and Gametogenesis
cloaca43.2 Fertilization
clonal selection42.2 Adaptive Immune Response
closed circulatory system40.1 Overview of the Circulatory System
club mosses25.4 Seedless Vascular Plants
Cnidaria28.2 Phylum Cnidaria
cnidocytes28.2 Phylum Cnidaria
cochlea36.4 Hearing and Vestibular Sensation
codominance12.2 Characteristics and Traits
codons15.1 The Genetic Code
coelom27.2 Features Used to Classify Animals
coenocytic hyphae24.1 Characteristics of Fungi
coenzymes6.5 Enzymes
cofactors6.5 Enzymes
cognitive learning45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
cohesin11.1 The Process of Meiosis
cohesion2.2 Water
coleoptile32.2 Pollination and Fertilization
coleorhiza32.2 Pollination and Fertilization
colinear15.1 The Genetic Code
Collenchyma cells30.2 Stems
colloid37.5 Endocrine Glands
Columnar epithelial33.2 Animal Primary Tissues
commensal45.6 Community Ecology
Commensalism24.4 Fungal Parasites and Pathogens
community1.2 Themes and Concepts of Biology
Compact bone38.2 Bone
Companion cells30.2 Stems
competitive exclusion principle45.6 Community Ecology
competitive inhibition6.5 Enzymes
complement system42.1 Innate Immune Response
complementary DNA (cDNA) libraries17.2 Mapping Genomes
compliance39.3 Breathing
compound leaf30.4 Leaves
compounds2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
concentration gradient5.2 Passive Transport
conceptual model46.1 Ecology of Ecosystems
conclusion1.1 The Science of Biology
condensin10.2 The Cell Cycle
Conditioned behaviors45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Condyloid joints38.3 Joints and Skeletal Movement
cones36.5 Vision
Conifers26.2 Gymnosperms
conispiral28.3 Superphylum Lophotrochozoa
conjugation22.2 Structure of Prokaryotes
Connective tissues33.2 Animal Primary Tissues
consensus15.2 Prokaryotic Transcription
conspecifics44.1 The Scope of Ecology
contig17.3 Whole-Genome Sequencing
Continuous variation12.1 Mendel’s Experiments and the Laws of Probability
Contour feathers29.5 Birds
contraception43.5 Human Pregnancy and Birth
contractile vacuoles23.3 Groups of Protists
control group1.1 The Science of Biology
convergent evolution18.1 Understanding Evolution
Coral reefs44.4 Aquatic Biomes
core enzyme15.2 Prokaryotic Transcription
Corms30.2 Stems
cornea36.5 Vision
corolla26.3 Angiosperms
corona28.3 Superphylum Lophotrochozoa
coronary arteries40.3 Mammalian Heart and Blood Vessels
coronary veins40.3 Mammalian Heart and Blood Vessels
corpus callosum35.3 The Central Nervous System
cortex30.2 Stems, 41.2 The Kidneys and Osmoregulatory Organs
Cortical41.2 The Kidneys and Osmoregulatory Organs
cortical nephrons41.2 The Kidneys and Osmoregulatory Organs
corticosteroids37.3 Regulation of Body Processes
cortisol37.3 Regulation of Body Processes
cotyledons26.3 Angiosperms, 32.2 Pollination and Fertilization
countercurrent exchanger41.2 The Kidneys and Osmoregulatory Organs
countercurrent multiplier41.2 The Kidneys and Osmoregulatory Organs
Courtship displays45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
covalent bonds2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
coxal bones38.1 Types of Skeletal Systems
cranial bones38.1 Types of Skeletal Systems
cranial nerves35.4 The Peripheral Nervous System
Craniata29.1 Chordates
cranium29.1 Chordates
Crocodilia29.4 Reptiles
crops26.4 The Role of Seed Plants
Cross reactivity42.3 Antibodies
Cross-pollination32.2 Pollination and Fertilization
crossover11.1 The Process of Meiosis
Cryogenian period27.4 The Evolutionary History of the Animal Kingdom
Cryptochromes30.6 Plant Sensory Systems and Responses
cryptofauna44.4 Aquatic Biomes
ctenidia28.3 Superphylum Lophotrochozoa
Cuboidal epithelial33.2 Animal Primary Tissues
Cushing’s disease37.3 Regulation of Body Processes
cutaneous respiration29.3 Amphibians
cuticle30.4 Leaves, 30.5 Transport of Water and Solutes in Plants
cuttings32.3 Asexual Reproduction
cyanobacteria22.1 Prokaryotic Diversity
Cycads26.2 Gymnosperms
cyclic AMP (cAMP)9.2 Propagation of the Signal
cyclin-dependent kinases10.3 Control of the Cell Cycle
cyclins10.3 Control of the Cell Cycle
cypris28.4 Superphylum Ecdysozoa
cytochrome complex8.2 The Light-Dependent Reactions of Photosynthesis
Cytogenetic mapping17.2 Mapping Genomes
cytokine42.1 Innate Immune Response
Cytokinesis10.2 The Cell Cycle
cytokinin30.6 Plant Sensory Systems and Responses
cytopathic21.2 Virus Infections and Hosts
cytoplasm4.3 Eukaryotic Cells
cytoplasmic streaming23.3 Groups of Protists
cytoskeleton4.5 The Cytoskeleton
cytosol4.3 Eukaryotic Cells
cytotoxic T lymphocytes (CTLs)42.2 Adaptive Immune Response
D
dead space39.3 Breathing
dead zone46.3 Biogeochemical Cycles
death rate (D)45.3 Environmental Limits to Population Growth
decomposers22.3 Prokaryotic Metabolism
Deductive reasoning1.1 The Science of Biology
degenerate15.1 The Genetic Code
dehydration synthesis3.1 Synthesis of Biological Macromolecules
demographic-based models45.4 Population Dynamics and Regulation
demography45.1 Population Demography
denaturation3.4 Proteins
denature6.5 Enzymes
Dendrites35.1 Neurons and Glial Cells
Dendritic cells42.2 Adaptive Immune Response
denitrification22.3 Prokaryotic Metabolism
density-dependent45.4 Population Dynamics and Regulation
density-independent45.4 Population Dynamics and Regulation
dentary29.6 Mammals
deoxynucleotide17.3 Whole-Genome Sequencing
deoxyribonucleic acid (DNA)3.5 Nucleic Acids
dephosphorylation7.1 Energy in Living Systems
depolarization35.2 How Neurons Communicate
Depression38.3 Joints and Skeletal Movement
Dermal tissue30.1 The Plant Body
descending41.2 The Kidneys and Osmoregulatory Organs
Descriptive (or discovery) science1.1 The Science of Biology
desmosomes4.6 Connections between Cells and Cellular Activities
determinate cleavage27.2 Features Used to Classify Animals
detrital food web46.1 Ecology of Ecosystems
Deuteromycota24.2 Classifications of Fungi
Deuterostomes27.2 Features Used to Classify Animals
diabetes insipidus37.3 Regulation of Body Processes
diabetes mellitus37.3 Regulation of Body Processes
diabetogenic effect37.3 Regulation of Body Processes
diacylglycerol (DAG)9.2 Propagation of the Signal
diaphragm39.1 Systems of Gas Exchange
diaphysis38.2 Bone
diapsids29.4 Reptiles
Diarthroses38.3 Joints and Skeletal Movement
diastole40.3 Mammalian Heart and Blood Vessels
dicer16.5 Eukaryotic Post-transcriptional Gene Regulation
dicots26.3 Angiosperms
dideoxynucleotides17.3 Whole-Genome Sequencing
Diffusion5.2 Passive Transport
Digestion34.3 Digestive System Processes
dihybrid12.3 Laws of Inheritance
dimer9.2 Propagation of the Signal
dimerization9.2 Propagation of the Signal
dioecious26.2 Gymnosperms
dipeptidase34.3 Digestive System Processes
diphyodonts29.6 Mammals
diploblasts27.2 Features Used to Classify Animals
diploid10.1 Cell Division
diploid-dominant11.2 Sexual Reproduction
directional selection19.3 Adaptive Evolution
Disaccharides3.2 Carbohydrates
discontinuous variation12.1 Mendel’s Experiments and the Laws of Probability
discussion1.1 The Science of Biology
Dispersal18.2 Formation of New Species
dissociation2.2 Water
distal convoluted tubule (DCT)41.2 The Kidneys and Osmoregulatory Organs
Distraction displays45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
divergent evolution18.1 Understanding Evolution
diversifying selection19.3 Adaptive Evolution
DNA barcoding47.4 Preserving Biodiversity
DNA microarrays17.3 Whole-Genome Sequencing
dominant lethal12.2 Characteristics and Traits
Dominant traits12.1 Mendel’s Experiments and the Laws of Probability
dormancy32.2 Pollination and Fertilization
dorsal cavity33.1 Animal Form and Function
dorsal hollow nerve cord29.1 Chordates
Dorsiflexion38.3 Joints and Skeletal Movement
double circulation40.1 Overview of the Circulatory System
double fertilization32.2 Pollination and Fertilization
down feathers29.5 Birds
down-regulation37.2 How Hormones Work
downstream15.2 Prokaryotic Transcription
duodenum34.1 Digestive Systems
dura mater35.3 The Central Nervous System
E
Eccrine glands29.6 Mammals
Ecdysozoa27.3 Animal Phylogeny
Echinodermata28.5 Superphylum Deuterostomia
Ecological pyramids46.2 Energy Flow through Ecosystems
Ecology44.1 The Scope of Ecology
ecosystem1.2 Themes and Concepts of Biology, 46.1 Ecology of Ecosystems
ecosystem diversity47.1 The Biodiversity Crisis
ecosystem dynamics46.1 Ecology of Ecosystems
ecosystem services44.4 Aquatic Biomes
Ectomycorrhizae24.3 Ecology of Fungi
ectothermic33.1 Animal Form and Function
Ediacaran period27.4 The Evolutionary History of the Animal Kingdom
effector cells42.2 Adaptive Immune Response
efferent arteriole41.2 The Kidneys and Osmoregulatory Organs
elastase34.3 Digestive System Processes
elastic recoil39.3 Breathing
elastic work39.3 Breathing
electrocardiogram (ECG)40.3 Mammalian Heart and Blood Vessels
electrochemical gradient5.3 Active Transport
electrogenic pump5.3 Active Transport
electrolyte41.1 Osmoregulation and Osmotic Balance
electrolytes2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
electromagnetic spectrum8.2 The Light-Dependent Reactions of Photosynthesis
electron configuration2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
electron microscopes4.1 Studying Cells
electron orbitals2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
electron transfer2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
electron transport chain8.2 The Light-Dependent Reactions of Photosynthesis
electronegativity2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Electrons2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
electrophoresis14.2 DNA Structure and Sequencing
Elements2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Elevation38.3 Joints and Skeletal Movement
embryophytes25.1 Early Plant Life
Emergent vegetation44.4 Aquatic Biomes
emerging disease22.4 Bacterial Diseases in Humans
Emsleyan/Mertensian mimicry45.6 Community Ecology
Enantiomers2.3 Carbon
Enantiornithes29.5 Birds
endemic44.2 Biogeography
endemic disease22.4 Bacterial Diseases in Humans
Endemic species47.1 The Biodiversity Crisis
endergonic reactions6.2 Potential, Kinetic, Free, and Activation Energy
endocardium40.3 Mammalian Heart and Blood Vessels
endocarp32.2 Pollination and Fertilization
Endochondral ossification38.2 Bone
endocrine34.4 Digestive System Regulation
endocrine cells9.1 Signaling Molecules and Cellular Receptors
endocrine glands37.5 Endocrine Glands
endocrine signals9.1 Signaling Molecules and Cellular Receptors
Endocytosis5.4 Bulk Transport
endodermis30.3 Roots
endoplasmic reticulum (ER)4.4 The Endomembrane System and Proteins
endoskeleton38.1 Types of Skeletal Systems
endosperm32.2 Pollination and Fertilization
endospermic dicots32.2 Pollination and Fertilization
endosymbiosis23.1 Eukaryotic Origins
endosymbiotic theory23.1 Eukaryotic Origins
endotherm33.1 Animal Form and Function
energy budget45.2 Life Histories and Natural Selection
enhancers16.4 Eukaryotic Transcription Gene Regulation
enterocoelom28.5 Superphylum Deuterostomia
enterocoely27.2 Features Used to Classify Animals
enthalpy6.2 Potential, Kinetic, Free, and Activation Energy
entropy6.3 The Laws of Thermodynamics
envelope21.1 Viral Evolution, Morphology, and Classification
environmental disturbances45.6 Community Ecology
Enzyme-linked receptors9.1 Signaling Molecules and Cellular Receptors
Enzymes3.4 Proteins
eosinophil42.1 Innate Immune Response
Ependymal35.1 Neurons and Glial Cells
epicardium40.3 Mammalian Heart and Blood Vessels
epicotyl32.2 Pollination and Fertilization
epidemic22.4 Bacterial Diseases in Humans
epidermis28.2 Phylum Cnidaria, 30.2 Stems
epigenetic16.1 Regulation of Gene Expression
epilepsy35.5 Nervous System Disorders
epinephrine37.3 Regulation of Body Processes
epiphyseal plate38.2 Bone
epiphyses38.2 Bone
epiphyte31.3 Nutritional Adaptations of Plants
epistasis12.3 Laws of Inheritance
Epithelial tissues33.2 Animal Primary Tissues
epitopes42.2 Adaptive Immune Response
equilibrium2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks, 46.1 Ecology of Ecosystems
Erythropoietin (EPO)37.5 Endocrine Glands
esophagus34.1 Digestive Systems
essential31.1 Nutritional Requirements of Plants
essential nutrients34.2 Nutrition and Energy Production
estivation33.1 Animal Form and Function
estrogen37.1 Types of Hormones, 43.4 Hormonal Control of Human Reproduction
Estrogens37.5 Endocrine Glands
Estuaries44.4 Aquatic Biomes
ethology45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Ethylene30.6 Plant Sensory Systems and Responses
eucoelomates27.2 Features Used to Classify Animals
eukaryote-first20.3 Perspectives on the Phylogenetic Tree
eukaryotes1.2 Themes and Concepts of Biology
eukaryotic cells4.3 Eukaryotic Cells
eukaryotic initiation factor-2 (eIF-2)16.6 Eukaryotic Translational and Post-translational Gene Regulation
Eumetazoa27.3 Animal Phylogeny
euploid13.2 Chromosomal Basis of Inherited Disorders
Eutherian mammals29.6 Mammals
eutrophication46.3 Biogeochemical Cycles
evaporation2.2 Water
Eversion38.3 Joints and Skeletal Movement
evolution1.2 Themes and Concepts of Biology
evolutionary (Darwinian) fitness19.3 Adaptive Evolution
excitatory postsynaptic potential (EPSP)35.2 How Neurons Communicate
exergonic reactions6.2 Potential, Kinetic, Free, and Activation Energy
exine32.1 Reproductive Development and Structure
exocarp32.2 Pollination and Fertilization
Exocytosis5.4 Bulk Transport
exons15.4 RNA Processing in Eukaryotes
exoskeleton38.1 Types of Skeletal Systems
Exotic species47.3 Threats to Biodiversity
expiratory reserve volume (ERV)39.2 Gas Exchange across Respiratory Surfaces
exponential growth45.3 Environmental Limits to Population Growth
expressed sequence tag (EST)17.2 Mapping Genomes
extant25.1 Early Plant Life
Extension38.3 Joints and Skeletal Movement
external fertilization43.2 Fertilization
extinct25.1 Early Plant Life
extinction47.1 The Biodiversity Crisis
extinction rates47.1 The Biodiversity Crisis
extracellular digestion28.2 Phylum Cnidaria
extracellular domain9.1 Signaling Molecules and Cellular Receptors
extracellular matrix4.6 Connections between Cells and Cellular Activities
extremophiles22.1 Prokaryotic Diversity
F
F112.1 Mendel’s Experiments and the Laws of Probability
F212.1 Mendel’s Experiments and the Laws of Probability
facial bones38.1 Types of Skeletal Systems
facilitated transport5.2 Passive Transport
FACT15.3 Eukaryotic Transcription
faculative anaerobes24.1 Characteristics of Fungi
fallout46.3 Biogeochemical Cycles
false negative17.5 Genomics and Proteomics
falsifiable1.1 The Science of Biology
family20.1 Organizing Life on Earth
Fecundity45.2 Life Histories and Natural Selection
Feedback inhibition6.5 Enzymes
femur38.1 Types of Skeletal Systems
fermentation7.5 Metabolism without Oxygen
ferns25.4 Seedless Vascular Plants
fertilization11.1 The Process of Meiosis
FEV1/FVC ratio39.2 Gas Exchange across Respiratory Surfaces
Fibrous connective tissues33.2 Animal Primary Tissues
fibrous joints38.3 Joints and Skeletal Movement
fibrous root system30.3 Roots
fibula38.1 Types of Skeletal Systems
field36.1 Sensory Processes
filament26.3 Angiosperms
first messenger37.2 How Hormones Work
Fission43.1 Reproduction Methods
fixation8.3 Using Light Energy to Make Organic Molecules
fixed action pattern45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
flagella4.5 The Cytoskeleton
flame cells41.3 Excretion Systems
Flat bones38.2 Bone
Flexion38.3 Joints and Skeletal Movement
Flight feathers29.5 Birds
Flow-resistive39.3 Breathing
flower26.1 Evolution of Seed Plants
fluid mosaic model5.1 Components and Structure
follicle stimulating hormone (FSH)43.4 Hormonal Control of Human Reproduction
follicle-stimulating hormone (FSH)37.3 Regulation of Body Processes
food chain46.1 Ecology of Ecosystems
food web46.1 Ecology of Ecosystems
foodborne disease22.4 Bacterial Diseases in Humans
Foraging45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
forced expiratory volume (FEV)39.2 Gas Exchange across Respiratory Surfaces
forearm38.1 Types of Skeletal Systems
foreign DNA17.1 Biotechnology
Foundation species45.6 Community Ecology
founder effect19.1 Population Evolution
fovea36.5 Vision
Fragmentation43.1 Reproduction Methods
free energy6.2 Potential, Kinetic, Free, and Activation Energy
free nerve ending36.2 Somatosensation
frequency-dependent selection19.3 Adaptive Evolution
Frogs29.3 Amphibians
frontal lobe35.3 The Central Nervous System
frontal plane33.1 Animal Form and Function
fruit26.1 Evolution of Seed Plants
FtsZ10.5 Prokaryotic Cell Division
Functional groups2.3 Carbon
functional residual capacity (FRC)39.2 Gas Exchange across Respiratory Surfaces
functional vital capacity (FVC)39.3 Breathing
furcula29.5 Birds
fusiform33.1 Animal Form and Function
fusion21.2 Virus Infections and Hosts
G
G-protein37.2 How Hormones Work
G-protein-linked receptors9.1 Signaling Molecules and Cellular Receptors
G0 phase10.2 The Cell Cycle
G1 phase10.2 The Cell Cycle
G2 phase10.2 The Cell Cycle
gallbladder34.1 Digestive Systems
galls21.2 Virus Infections and Hosts
Gametangia25.1 Early Plant Life
gametes10.1 Cell Division
gametic barrier18.2 Formation of New Species
gametophyte32.1 Reproductive Development and Structure
gametophytes11.2 Sexual Reproduction
Gap junctions4.6 Connections between Cells and Cellular Activities
gastric inhibitory peptide34.4 Digestive System Regulation
gastric phase34.4 Digestive System Regulation
gastrin34.4 Digestive System Regulation
gastrodermis28.2 Phylum Cnidaria
gastrovascular cavity28.2 Phylum Cnidaria, 34.1 Digestive Systems
gastrula27.1 Features of the Animal Kingdom
gastrulation43.6 Fertilization and Early Embryonic Development
GC-rich boxes15.3 Eukaryotic Transcription
Gel electrophoresis17.1 Biotechnology
gemmae25.3 Bryophytes
Gemmules28.1 Phylum Porifera
gene expression16.1 Regulation of Gene Expression
gene flow19.2 Population Genetics
gene pool19.1 Population Evolution
Gene targeting17.1 Biotechnology
Gene therapy17.1 Biotechnology, 21.3 Prevention and Treatment of Viral Infections
gene transfer agents (GTAs)20.3 Perspectives on the Phylogenetic Tree
genes10.1 Cell Division
genetic diagnosis17.1 Biotechnology
Genetic diversity47.1 The Biodiversity Crisis
genetic drift19.2 Population Genetics
Genetic engineering17.1 Biotechnology
genetic map17.2 Mapping Genomes
genetic marker17.2 Mapping Genomes
genetic recombination17.2 Mapping Genomes
genetic structure19.1 Population Evolution
genetic testing17.1 Biotechnology
genetic variance19.2 Population Genetics
genetically modified organism17.1 Biotechnology
genome10.1 Cell Division
genome annotation17.3 Whole-Genome Sequencing
genome fusion20.3 Perspectives on the Phylogenetic Tree
Genome mapping17.2 Mapping Genomes
genomic libraries17.2 Mapping Genomes
Genomics17.2 Mapping Genomes
genotype12.2 Characteristics and Traits
genus20.1 Organizing Life on Earth
geographical variation19.2 Population Genetics
Geometric isomers2.3 Carbon
germ cells11.2 Sexual Reproduction
germ layers27.1 Features of the Animal Kingdom
gestation43.5 Human Pregnancy and Birth
Gibberellins30.6 Plant Sensory Systems and Responses
gigantism37.3 Regulation of Body Processes
gill circulation40.1 Overview of the Circulatory System
gingkophytes26.2 Gymnosperms
gizzard34.1 Digestive Systems
glabrous36.2 Somatosensation
glia35.1 Neurons and Glial Cells
Gliding movements38.3 Joints and Skeletal Movement
Global climate change44.5 Climate and the Effects of Global Climate Change
Glomeromycota24.2 Classifications of Fungi
glomerular filtration41.2 The Kidneys and Osmoregulatory Organs
Glomerular filtration rate (GFR)41.2 The Kidneys and Osmoregulatory Organs
glomeruli36.3 Taste and Smell
glomerulus41.2 The Kidneys and Osmoregulatory Organs
glucagon37.3 Regulation of Body Processes
glucocorticoids37.3 Regulation of Body Processes
gluconeogenesis37.3 Regulation of Body Processes
glucose-sparing effect37.3 Regulation of Body Processes
GLUT proteins7.7 Regulation of Cellular Respiration
Glycogen3.2 Carbohydrates
glycogenolysis37.3 Regulation of Body Processes
glycolipids5.1 Components and Structure
Glycolysis7.2 Glycolysis
glycoproteins5.1 Components and Structure
glycosidic bond3.2 Carbohydrates
Gnathostomes29.2 Fishes
Gnetophytes26.2 Gymnosperms
goiter37.3 Regulation of Body Processes
Golgi apparatus4.4 The Endomembrane System and Proteins
Golgi tendon organs36.2 Somatosensation
Gomphoses38.3 Joints and Skeletal Movement
gonadotropin-releasing hormone (GnRH)43.4 Hormonal Control of Human Reproduction
gonadotropins37.3 Regulation of Body Processes
good genes hypothesis19.3 Adaptive Evolution
Gorilla29.7 The Evolution of Primates
gradual speciation model18.3 Reconnection and Rates of Speciation
grafting32.3 Asexual Reproduction
Gram negative22.2 Structure of Prokaryotes
Gram positive22.2 Structure of Prokaryotes
granum8.1 Overview of Photosynthesis
granzyme42.1 Innate Immune Response
grazing food web46.1 Ecology of Ecosystems
greenhouse effect44.5 Climate and the Effects of Global Climate Change
greenhouse gases44.5 Climate and the Effects of Global Climate Change
gross primary productivity46.2 Energy Flow through Ecosystems
Ground tissue30.1 The Plant Body
Group I21.1 Viral Evolution, Morphology, and Classification
Group II21.1 Viral Evolution, Morphology, and Classification
Group III21.1 Viral Evolution, Morphology, and Classification
Group IV21.1 Viral Evolution, Morphology, and Classification
Group V21.1 Viral Evolution, Morphology, and Classification
Group VI21.1 Viral Evolution, Morphology, and Classification
Group VII21.1 Viral Evolution, Morphology, and Classification
growth factors9.3 Response to the Signal
Growth hormone (GH)37.3 Regulation of Body Processes
growth hormone-inhibiting hormone (GHIH)37.3 Regulation of Body Processes
growth hormone-releasing hormone (GHRH)37.3 Regulation of Body Processes
guanosine diphosphate (GDP)16.6 Eukaryotic Translational and Post-translational Gene Regulation
guanosine triphosphate (GTP)16.6 Eukaryotic Translational and Post-translational Gene Regulation
guard cells30.2 Stems
gustation36.3 Taste and Smell
Gymnosperms26.2 Gymnosperms
gynoecium26.3 Angiosperms, 32.1 Reproductive Development and Structure
gyri35.3 The Central Nervous System
H
habitat isolation18.2 Formation of New Species
Habituation45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Hagfishes29.2 Fishes
hairpin15.2 Prokaryotic Transcription
handicap principle19.3 Adaptive Evolution
haploid10.1 Cell Division
haploid-dominant11.2 Sexual Reproduction
haustoria24.1 Characteristics of Fungi
Haversian canal38.2 Bone
haze-effect cooling44.5 Climate and the Effects of Global Climate Change
Heat energy6.2 Potential, Kinetic, Free, and Activation Energy, 6.3 The Laws of Thermodynamics
heat of vaporization2.2 Water
Heirloom seeds26.4 The Role of Seed Plants
helicase14.4 DNA Replication in Prokaryotes
helper T (TH) lymphocytes42.2 Adaptive Immune Response
heme group39.4 Transport of Gases in Human Bodily Fluids
hemizygous12.2 Characteristics and Traits
hemocoel28.4 Superphylum Ecdysozoa, 40.1 Overview of the Circulatory System
Hemoglobin39.4 Transport of Gases in Human Bodily Fluids
hemolymph40.1 Overview of the Circulatory System
herbaceous26.3 Angiosperms
Herbivores34.1 Digestive Systems
herbivory26.4 The Role of Seed Plants
Heritability19.2 Population Genetics
hermaphrodites28.4 Superphylum Ecdysozoa
Hermaphroditism43.1 Reproduction Methods
heterodont teeth29.6 Mammals
heterogeneity47.1 The Biodiversity Crisis
heterospecifics44.1 The Scope of Ecology
heterosporous25.1 Early Plant Life
Heterothallic24.1 Characteristics of Fungi
heterotrophs8.1 Overview of Photosynthesis
heterozygous12.2 Characteristics and Traits
hibernation33.1 Animal Form and Function
hilum41.2 The Kidneys and Osmoregulatory Organs
hinge joints38.3 Joints and Skeletal Movement
hippocampus35.3 The Central Nervous System
histone acetylation16.7 Cancer and Gene Regulation
histone proteins10.1 Cell Division
holistic ecosystem model46.1 Ecology of Ecosystems
holoblastic43.6 Fertilization and Early Embryonic Development
holoenzyme15.2 Prokaryotic Transcription
homeostasis1.2 Themes and Concepts of Biology, 33.3 Homeostasis
hominin29.7 The Evolution of Primates
hominoids29.7 The Evolution of Primates
Homo29.7 The Evolution of Primates
Homo sapiens sapiens29.7 The Evolution of Primates
homologous10.1 Cell Division
homologous recombination13.1 Chromosomal Theory and Genetic Linkage
homologous structures18.1 Understanding Evolution
homosporous25.1 Early Plant Life
homothallic24.1 Characteristics of Fungi
homozygous12.2 Characteristics and Traits
honest signal19.3 Adaptive Evolution
horizon31.2 The Soil
Horizontal gene transfer (HGT)20.3 Perspectives on the Phylogenetic Tree
horizontal transmission21.2 Virus Infections and Hosts
Hormonal stimuli37.4 Regulation of Hormone Production
hormone37.2 How Hormones Work
Hormones3.4 Proteins
hornworts25.3 Bryophytes
horsetails25.4 Seedless Vascular Plants
hostIntroduction, 45.6 Community Ecology
host DNA17.1 Biotechnology
Hox genes27.1 Features of the Animal Kingdom
human beta chorionic gonadotropin (β-HCG)43.5 Human Pregnancy and Birth
humerus38.1 Types of Skeletal Systems
humoral immune response42.2 Adaptive Immune Response
humoral stimulus37.4 Regulation of Hormone Production
humus31.2 The Soil
hybrid18.2 Formation of New Species
hybrid inviability18.2 Formation of New Species
hybrid zone18.3 Reconnection and Rates of Speciation
hybridizations12.1 Mendel’s Experiments and the Laws of Probability
Hydrocarbons2.3 Carbon
hydrogen bond2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
hydrogenosomes23.3 Groups of Protists
hydrolysis reactions3.1 Synthesis of Biological Macromolecules
hydrophilic2.2 Water, 5.1 Components and Structure
hydrophobic2.2 Water, 5.1 Components and Structure
hydrosphere46.3 Biogeochemical Cycles
hydrostatic skeleton38.1 Types of Skeletal Systems
hydrothermal vent22.1 Prokaryotic Diversity
Hylobatidae29.7 The Evolution of Primates
Hylonomus29.4 Reptiles
hyoid bone38.1 Types of Skeletal Systems
hyperextension38.3 Joints and Skeletal Movement
hyperglycemia37.3 Regulation of Body Processes
hyperopia36.5 Vision
hyperplasia21.2 Virus Infections and Hosts
hyperpolarizes35.2 How Neurons Communicate
hypersensitivities42.4 Disruptions in the Immune System
Hyperthyroidism37.3 Regulation of Body Processes
hypertonic5.2 Passive Transport
hypha24.1 Characteristics of Fungi
hyphae24.1 Characteristics of Fungi
hypocotyl32.2 Pollination and Fertilization
hypoglycemia37.3 Regulation of Body Processes
hypophyseal portal system37.5 Endocrine Glands
hypoplasia21.2 Virus Infections and Hosts
hypothalamus35.3 The Central Nervous System, 37.5 Endocrine Glands
hypothesis1.1 The Science of Biology
hypothesis-based science1.1 The Science of Biology
Hypothyroidism37.3 Regulation of Body Processes
hypotonic5.2 Passive Transport
I
ileum34.1 Digestive Systems
immune tolerance42.2 Adaptive Immune Response
Immunodeficiency42.4 Disruptions in the Immune System
Imprinting45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
inbreeding19.2 Population Genetics
inbreeding depression19.2 Population Genetics
incomplete dominance12.2 Characteristics and Traits
incus36.4 Hearing and Vestibular Sensation
indeterminate cleavage27.2 Features Used to Classify Animals
induced fit6.5 Enzymes
Induced mutations14.6 DNA Repair
inducible operons16.2 Prokaryotic Gene Regulation
Inductive reasoning1.1 The Science of Biology
inert gases2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
inferior vena cava40.3 Mammalian Heart and Blood Vessels, 41.2 The Kidneys and Osmoregulatory Organs
Infertility43.5 Human Pregnancy and Birth
inflammation42.1 Innate Immune Response
ingestion34.3 Digestive System Processes
inhibin43.4 Hormonal Control of Human Reproduction
inhibitor9.3 Response to the Signal
inhibitory postsynaptic potentials (IPSPs)35.2 How Neurons Communicate
initiation complex16.6 Eukaryotic Translational and Post-translational Gene Regulation
initiation site15.2 Prokaryotic Transcription
initiator tRNA15.5 Ribosomes and Protein Synthesis
innate behaviors45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Innate immunity42.1 Innate Immune Response
inner cell mass43.6 Fertilization and Early Embryonic Development
inner ear36.4 Hearing and Vestibular Sensation
inorganic compound31.1 Nutritional Requirements of Plants
inositol phospholipids9.2 Propagation of the Signal
inositol triphosphate (IP3)9.2 Propagation of the Signal
insectivorous31.3 Nutritional Adaptations of Plants
inspiratory capacity (IC)39.2 Gas Exchange across Respiratory Surfaces
inspiratory reserve volume (IRV)39.2 Gas Exchange across Respiratory Surfaces
Insulin37.3 Regulation of Body Processes
insulin-like growth factors (IGFs)37.3 Regulation of Body Processes
Integral proteins5.1 Components and Structure
integument26.2 Gymnosperms
Intercalary meristems30.1 The Plant Body
intercellular signaling9.1 Signaling Molecules and Cellular Receptors
intercostal muscles39.3 Breathing
interferon42.1 Innate Immune Response
interkinesis11.1 The Process of Meiosis
interlobar arteries41.2 The Kidneys and Osmoregulatory Organs
Intermediate filaments4.5 The Cytoskeleton
intermittent21.2 Virus Infections and Hosts
internal fertilization43.2 Fertilization
Internal receptors9.1 Signaling Molecules and Cellular Receptors
internode30.2 Stems
interphase10.2 The Cell Cycle
intersexual selection45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
interspecific competition45.4 Population Dynamics and Regulation
interstitial cells of Leydig43.4 Hormonal Control of Human Reproduction
interstitial fluid40.1 Overview of the Circulatory System
intertidal zone44.4 Aquatic Biomes
Intervertebral discs38.1 Types of Skeletal Systems
intestinal phase34.4 Digestive System Regulation
intine32.1 Reproductive Development and Structure
intracellular hormone receptors37.2 How Hormones Work
intracellular mediators9.1 Signaling Molecules and Cellular Receptors
intracellular signaling9.1 Signaling Molecules and Cellular Receptors
Intramembranous ossification38.2 Bone
intrapleural space39.3 Breathing
intrasexual selection45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
intraspecific competition45.3 Environmental Limits to Population Growth
introduction1.1 The Science of Biology
introns15.4 RNA Processing in Eukaryotes
Inversion38.3 Joints and Skeletal Movement
invertebrata28.1 Phylum Porifera
Ion channel-linked receptors9.1 Signaling Molecules and Cellular Receptors
Ionic bonds2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
ions2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
iris36.5 Vision
Irregular bones38.2 Bone
irreversible2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
island biogeography45.6 Community Ecology
islets of Langerhans37.5 Endocrine Glands
isomerase7.2 Glycolysis
isomers2.3 Carbon
isotonic5.2 Passive Transport
Isotopes2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
isthmus37.5 Endocrine Glands
Iteroparity45.2 Life Histories and Natural Selection
J
J-shaped growth curve45.3 Environmental Limits to Population Growth
Jasmonates30.6 Plant Sensory Systems and Responses
jejunum34.1 Digestive Systems
joint38.3 Joints and Skeletal Movement
juxtaglomerular cells41.2 The Kidneys and Osmoregulatory Organs
juxtamedullary nephrons41.2 The Kidneys and Osmoregulatory Organs
K
K-selected species45.4 Population Dynamics and Regulation
karyogamy24.1 Characteristics of Fungi
karyogram13.2 Chromosomal Basis of Inherited Disorders
karyokinesis10.2 The Cell Cycle
karyotype13.2 Chromosomal Basis of Inherited Disorders
keystone species45.6 Community Ecology
kidneys41.2 The Kidneys and Osmoregulatory Organs
kin selection45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
kinase9.2 Propagation of the Signal
kinesis45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
kinesthesia36.1 Sensory Processes
kinetic energy6.2 Potential, Kinetic, Free, and Activation Energy
kinetochore10.2 The Cell Cycle
kinetoplast23.3 Groups of Protists
kingdom20.1 Organizing Life on Earth
Kozak’s rules15.5 Ribosomes and Protein Synthesis
Krebs cycle7.3 Oxidation of Pyruvate and the Citric Acid Cycle
L
labia majora43.3 Human Reproductive Anatomy and Gametogenesis
labia minora43.3 Human Reproductive Anatomy and Gametogenesis
labyrinth36.4 Hearing and Vestibular Sensation
lac operon16.2 Prokaryotic Gene Regulation
lactases34.3 Digestive System Processes
lacunae33.2 Animal Primary Tissues
lagging strand14.4 DNA Replication in Prokaryotes
lamellae38.2 Bone
lamina30.4 Leaves
Lampreys29.2 Fishes
lancelets29.1 Chordates
large intestine34.1 Digestive Systems
larynx39.1 Systems of Gas Exchange
latency21.2 Virus Infections and Hosts
lateral line29.2 Fishes
Lateral meristems30.1 The Plant Body
lateral rotation38.3 Joints and Skeletal Movement
law of dominance12.3 Laws of Inheritance
law of independent assortment12.3 Laws of Inheritance
law of mass action2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
law of segregation12.3 Laws of Inheritance
Layering32.3 Asexual Reproduction
leading strand14.4 DNA Replication in Prokaryotes
learned behaviors45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
lens36.5 Vision
lenticels30.2 Stems
lepidosaurs29.4 Reptiles
leptin37.5 Endocrine Glands
Lichens24.3 Ecology of Fungi
life cycles11.2 Sexual Reproduction
life history45.2 Life Histories and Natural Selection
life sciences1.1 The Science of Biology
life tables45.1 Population Demography
ligand9.1 Signaling Molecules and Cellular Receptors
ligase14.4 DNA Replication in Prokaryotes
light microscopes4.1 Studying Cells
light-dependent reactions8.1 Overview of Photosynthesis
light-harvesting complex8.2 The Light-Dependent Reactions of Photosynthesis
light-independent reactions8.1 Overview of Photosynthesis
lignin25.4 Seedless Vascular Plants
limbic system35.3 The Central Nervous System
linkage12.3 Laws of Inheritance
linkage analysis17.2 Mapping Genomes
lipase34.1 Digestive Systems
lipid hormones37.1 Types of Hormones
Lipids3.3 Lipids
litmus2.2 Water
liver34.1 Digestive Systems
Liverworts25.3 Bryophytes
loams31.2 The Soil
lobe35.3 The Central Nervous System, 35.3 The Central Nervous System, 35.3 The Central Nervous System
lobes of the kidney41.2 The Kidneys and Osmoregulatory Organs
locus10.1 Cell Division
logistic growth45.3 Environmental Limits to Population Growth
Long bones38.2 Bone
Long-term depression (LTD)35.2 How Neurons Communicate
Long-term potentiation (LTP)35.2 How Neurons Communicate
loop of Henle41.2 The Kidneys and Osmoregulatory Organs
Loose connective tissue33.2 Animal Primary Tissues
Lophotrochozoa27.3 Animal Phylogeny
lower limb38.1 Types of Skeletal Systems
lung capacities39.2 Gas Exchange across Respiratory Surfaces
lung volumes39.2 Gas Exchange across Respiratory Surfaces
luteinizing hormone (LH)43.4 Hormonal Control of Human Reproduction
Lycopodiophyta25.4 Seedless Vascular Plants
Lymph42.2 Adaptive Immune Response
Lymph nodes40.4 Blood Flow and Blood Pressure Regulation
Lymphocytes42.1 Innate Immune Response
lysis21.2 Virus Infections and Hosts
lysis buffer17.1 Biotechnology
lysogenic cycle21.2 Virus Infections and Hosts
lysosomes4.3 Eukaryotic Cells
lytic cycle21.2 Virus Infections and Hosts
M
macroevolution19.1 Population Evolution
macromolecules1.2 Themes and Concepts of Biology
macronutrients31.1 Nutritional Requirements of Plants
macrophage42.1 Innate Immune Response
macula densa41.2 The Kidneys and Osmoregulatory Organs
madreporite28.5 Superphylum Deuterostomia
Major depression35.5 Nervous System Disorders
major histocompatibility class (MHC) I molecules42.1 Innate Immune Response
malleus36.4 Hearing and Vestibular Sensation
Malpighian tubules41.3 Excretion Systems
maltases34.3 Digestive System Processes
Mammals29.6 Mammals
Mammary glands29.6 Mammals
mantle28.3 Superphylum Lophotrochozoa
mark and recapture45.1 Population Demography
Marsupials29.6 Mammals
mass extinction27.4 The Evolutionary History of the Animal Kingdom
mass number2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
mast cell42.1 Innate Immune Response
mastax28.3 Superphylum Lophotrochozoa
materials and methods1.1 The Science of Biology
mating factor9.4 Signaling in Single-Celled Organisms
matrix33.2 Animal Primary Tissues
matrix proteins21.1 Viral Evolution, Morphology, and Classification
Matter2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
maximum parsimony20.2 Determining Evolutionary Relationships
mechanoreceptor36.1 Sensory Processes
medial rotation38.3 Joints and Skeletal Movement
medulla41.2 The Kidneys and Osmoregulatory Organs
medusa28.2 Phylum Cnidaria
megafauna47.1 The Biodiversity Crisis
megagametogenesis32.1 Reproductive Development and Structure
megapascals30.5 Transport of Water and Solutes in Plants
megaphylls25.4 Seedless Vascular Plants
megasporangium32.1 Reproductive Development and Structure
megaspores25.1 Early Plant Life
megasporocyte26.2 Gymnosperms
megasporogenesis32.1 Reproductive Development and Structure
megasporophylls32.1 Reproductive Development and Structure
meiosis11.1 The Process of Meiosis
meiosis I11.1 The Process of Meiosis
Meiosis II11.1 The Process of Meiosis
Meissner’s corpuscles36.2 Somatosensation
membrane potential35.2 How Neurons Communicate
memory cell42.2 Adaptive Immune Response
meninges35.3 The Central Nervous System
menopause43.4 Hormonal Control of Human Reproduction
menstrual cycle43.4 Hormonal Control of Human Reproduction
Meristematic tissue30.1 The Plant Body
meristems30.1 The Plant Body
Merkel’s disks36.2 Somatosensation
meroblastic43.6 Fertilization and Early Embryonic Development
mesocarp32.2 Pollination and Fertilization
mesocosm46.1 Ecology of Ecosystems
mesoglea28.2 Phylum Cnidaria
Mesohyl28.1 Phylum Porifera
mesophyll8.1 Overview of Photosynthesis
messenger RNA (mRNA)3.5 Nucleic Acids
metabolism6.1 Energy and Metabolism
metabolome17.5 Genomics and Proteomics
Metabolomics17.5 Genomics and Proteomics
metacarpus38.1 Types of Skeletal Systems
Metagenomics17.4 Applying Genomics
metamerism28.3 Superphylum Lophotrochozoa
metaphase10.2 The Cell Cycle
metaphase plate10.2 The Cell Cycle
metatarsals38.1 Types of Skeletal Systems
Metazoa27.3 Animal Phylogeny
methicillin-resistant Staphylococcus aureus (MRSA)22.4 Bacterial Diseases in Humans
MHC II molecules42.1 Innate Immune Response
microbial mat22.1 Prokaryotic Diversity
Microbiology1.2 Themes and Concepts of Biology
microcosm46.1 Ecology of Ecosystems
microevolution19.1 Population Evolution
microfilaments4.5 The Cytoskeleton
Microglia35.1 Neurons and Glial Cells
micronutrients31.1 Nutritional Requirements of Plants
microphyll25.4 Seedless Vascular Plants
Micropropagation32.3 Asexual Reproduction
micropyle32.1 Reproductive Development and Structure
microRNAs16.5 Eukaryotic Post-transcriptional Gene Regulation
microsatellite polymorphisms17.2 Mapping Genomes
microscope4.1 Studying Cells
microsporangium32.1 Reproductive Development and Structure
microspores25.1 Early Plant Life
microsporocytes26.2 Gymnosperms
microsporophylls32.1 Reproductive Development and Structure
microtubules4.5 The Cytoskeleton
microvilli41.3 Excretion Systems
middle ear36.4 Hearing and Vestibular Sensation
midsagittal plane33.1 Animal Form and Function
Migration45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Milankovitch cycles44.5 Climate and the Effects of Global Climate Change
mineral soils31.2 The Soil
mineralocorticoid37.3 Regulation of Body Processes
Minerals34.2 Nutrition and Energy Production
mismatch repair14.6 DNA Repair
Mitochondria4.3 Eukaryotic Cells
mitochondria-first20.3 Perspectives on the Phylogenetic Tree
mitosis10.2 The Cell Cycle
mitosomes23.3 Groups of Protists
mitotic phase10.2 The Cell Cycle
mitotic spindle10.2 The Cell Cycle
mixotrophs23.2 Characteristics of Protists
model organism17.3 Whole-Genome Sequencing
model system12.1 Mendel’s Experiments and the Laws of Probability
modern synthesis19.1 Population Evolution
molality41.1 Osmoregulation and Osmotic Balance
molarity41.1 Osmoregulation and Osmotic Balance
mold24.2 Classifications of Fungi
mole41.1 Osmoregulation and Osmotic Balance
molecular biology1.2 Themes and Concepts of Biology
molecular systematics20.2 Determining Evolutionary Relationships
molecule1.2 Themes and Concepts of Biology
Molecules2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Mollusca28.3 Superphylum Lophotrochozoa
monocarpic32.3 Asexual Reproduction
Monocots26.3 Angiosperms
monocyte42.1 Innate Immune Response
monoecious26.2 Gymnosperms
monogamous45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
monogastric34.1 Digestive Systems
monohybrid12.2 Characteristics and Traits
monomers3.1 Synthesis of Biological Macromolecules
monophyletic group20.2 Determining Evolutionary Relationships
Monosaccharides3.2 Carbohydrates
monosomy13.2 Chromosomal Basis of Inherited Disorders
monotremes29.6 Mammals
mortality rate45.1 Population Demography
mosses25.3 Bryophytes
motor end plate38.4 Muscle Contraction and Locomotion
mucin39.1 Systems of Gas Exchange
Mucosa-associated lymphoid tissue (MALT)42.2 Adaptive Immune Response
mucus39.1 Systems of Gas Exchange
Müllerian mimicry45.6 Community Ecology
multiple cloning site (MCS)17.1 Biotechnology
Multiple fruit32.2 Pollination and Fertilization
Muscle spindles36.2 Somatosensation
Mutations14.6 DNA Repair
mutualism45.6 Community Ecology
Myc16.7 Cancer and Gene Regulation
mycelium24.1 Characteristics of Fungi
Mycetismus24.4 Fungal Parasites and Pathogens
mycology24.1 Characteristics of Fungi
Mycorrhiza24.3 Ecology of Fungi
mycorrhizaeIntroduction
mycosis24.4 Fungal Parasites and Pathogens
Mycotoxicosis24.4 Fungal Parasites and Pathogens
myelin35.1 Neurons and Glial Cells
myocardial infarction40.3 Mammalian Heart and Blood Vessels
myocardium40.3 Mammalian Heart and Blood Vessels
myofibrils38.4 Muscle Contraction and Locomotion
myofilaments38.4 Muscle Contraction and Locomotion
Myopia36.5 Vision
myosin38.4 Muscle Contraction and Locomotion
Myxini29.2 Fishes
N
nacre28.3 Superphylum Lophotrochozoa
nasal cavity39.1 Systems of Gas Exchange
natural killer (NK) cells42.1 Innate Immune Response
natural sciences1.1 The Science of Biology
Natural selection18.1 Understanding Evolution
nauplius28.4 Superphylum Ecdysozoa
nectar26.4 The Role of Seed Plants
nectar guide32.2 Pollination and Fertilization
negative feedback loop33.3 Homeostasis
negative gravitropism30.6 Plant Sensory Systems and Responses
negative polarity21.1 Viral Evolution, Morphology, and Classification
negative regulators16.2 Prokaryotic Gene Regulation
nematocysts28.2 Phylum Cnidaria
Nematoda28.4 Superphylum Ecdysozoa
Nemertea28.3 Superphylum Lophotrochozoa
Neognathae29.5 Birds
Neornithes29.5 Birds
nephridia41.3 Excretion Systems
nephridiopore41.3 Excretion Systems
nephrons41.2 The Kidneys and Osmoregulatory Organs
neritic zone44.4 Aquatic Biomes
Net consumer productivity46.2 Energy Flow through Ecosystems
Net primary productivity44.2 Biogeography, 46.2 Energy Flow through Ecosystems
Net production efficiency (NPE)46.2 Energy Flow through Ecosystems
neural stimuli37.4 Regulation of Hormone Production
neural tube43.7 Organogenesis and Vertebrate Formation
neurobiology1.2 Themes and Concepts of Biology
Neurodegenerative disorders35.5 Nervous System Disorders
neurons35.1 Neurons and Glial Cells
neurotransmitters9.1 Signaling Molecules and Cellular Receptors
neutron2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
neutrophil42.1 Innate Immune Response
next-generation sequencing17.3 Whole-Genome Sequencing
Nitrification22.3 Prokaryotic Metabolism
nitrogen fixation22.3 Prokaryotic Metabolism
nitrogenase31.3 Nutritional Adaptations of Plants
noble gases2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
nociception36.2 Somatosensation
Nodes30.2 Stems
nodes of Ranvier35.1 Neurons and Glial Cells
nodules22.5 Beneficial Prokaryotes, 31.3 Nutritional Adaptations of Plants
non-electrolyte41.1 Osmoregulation and Osmotic Balance
non-endospermic dicots32.2 Pollination and Fertilization
non-renewable resource46.3 Biogeochemical Cycles
non-vascular plants25.1 Early Plant Life
nondisjunction13.2 Chromosomal Basis of Inherited Disorders
nonparental types13.1 Chromosomal Theory and Genetic Linkage
Nonpolar covalent bonds2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
nonrandom mating19.2 Population Genetics
nonsense codons15.1 The Genetic Code
nontemplate strand15.2 Prokaryotic Transcription
norepinephrine35.4 The Peripheral Nervous System, 37.3 Regulation of Body Processes
northern blotting17.1 Biotechnology
notochord29.1 Chordates
nuclear envelope4.3 Eukaryotic Cells
Nucleic acids3.5 Nucleic Acids
nucleoid4.2 Prokaryotic Cells
nucleolus4.3 Eukaryotic Cells
nucleoplasm4.3 Eukaryotic Cells
nucleosome10.1 Cell Division
nucleotide excision repair14.6 DNA Repair
nucleotides3.5 Nucleic Acids
nucleus2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks, 4.3 Eukaryotic Cells
nucleus-first20.3 Perspectives on the Phylogenetic Tree
nutrients22.1 Prokaryotic Diversity, 22.3 Prokaryotic Metabolism
O
O horizon31.2 The Soil
obligate aerobes24.1 Characteristics of Fungi
obligate anaerobes24.1 Characteristics of Fungi
Obstructive diseases39.3 Breathing
occipital35.3 The Central Nervous System
Ocean upwelling44.2 Biogeography
oceanic zone44.4 Aquatic Biomes
octamer boxes15.3 Eukaryotic Transcription
octet rule2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Odorants36.3 Taste and Smell
Okazaki fragments14.4 DNA Replication in Prokaryotes
olfaction36.3 Taste and Smell
olfactory bulb36.3 Taste and Smell
olfactory epithelium36.3 Taste and Smell
olfactory receptor36.3 Taste and Smell
Oligodendrocytes35.1 Neurons and Glial Cells
Oligosaccharins30.6 Plant Sensory Systems and Responses
Omega3.3 Lipids
Omnivores34.1 Digestive Systems
oncogenes10.4 Cancer and the Cell Cycle
oncogenic viruses21.2 Virus Infections and Hosts
Oncolytic viruses21.3 Prevention and Treatment of Viral Infections
one-child policy45.5 Human Population Growth
oogenesis43.3 Human Reproductive Anatomy and Gametogenesis
open circulatory system40.1 Overview of the Circulatory System
operant conditioning45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
operator16.2 Prokaryotic Gene Regulation
operons16.2 Prokaryotic Gene Regulation
Opposition38.3 Joints and Skeletal Movement
opsonization42.1 Innate Immune Response
orbitals2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
order20.1 Organizing Life on Earth
organ of Corti36.4 Hearing and Vestibular Sensation
organ system1.2 Themes and Concepts of Biology
organelles1.2 Themes and Concepts of Biology, 4.3 Eukaryotic Cells
organic compound31.1 Nutritional Requirements of Plants
organic molecules2.3 Carbon
organic soils31.2 The Soil
Organisms1.2 Themes and Concepts of Biology
organogenesis27.1 Features of the Animal Kingdom, 43.7 Organogenesis and Vertebrate Formation
Organs1.2 Themes and Concepts of Biology
origin10.5 Prokaryotic Cell Division
Ornithorhynchidae29.6 Mammals
osculum28.1 Phylum Porifera
osmoconformers41.1 Osmoregulation and Osmotic Balance
Osmolarity5.2 Passive Transport
osmoreceptors37.3 Regulation of Body Processes
Osmoregulation41.1 Osmoregulation and Osmotic Balance
osmoregulatory41.1 Osmoregulation and Osmotic Balance
Osmosis5.2 Passive Transport
osmotic balance41.1 Osmoregulation and Osmotic Balance
osmotic pressure41.1 Osmoregulation and Osmotic Balance
osseous tissue38.2 Bone
ossicles36.4 Hearing and Vestibular Sensation
Ossification38.2 Bone
Osteichthyes29.2 Fishes
Osteoblasts38.2 Bone
Osteoclasts38.2 Bone
Osteocytes38.2 Bone
osteons33.2 Animal Primary Tissues, 38.2 Bone
Osteoprogenitor cells38.2 Bone
ostia28.1 Phylum Porifera, 40.1 Overview of the Circulatory System
ostracoderms29.2 Fishes
outer ear36.4 Hearing and Vestibular Sensation
oval window36.4 Hearing and Vestibular Sensation
ovarian cycle43.4 Hormonal Control of Human Reproduction
ovary26.3 Angiosperms
oviducts43.3 Human Reproductive Anatomy and Gametogenesis
ovigers28.4 Superphylum Ecdysozoa
oviparity43.2 Fertilization
ovoviparity43.2 Fertilization
ovulate cones26.2 Gymnosperms
ovulation43.4 Hormonal Control of Human Reproduction
ovule26.1 Evolution of Seed Plants
oxidative phosphorylation7.1 Energy in Living Systems
oxygen dissociation curve39.4 Transport of Gases in Human Bodily Fluids
oxygen-carrying capacity39.4 Transport of Gases in Human Bodily Fluids
oxytocin37.3 Regulation of Body Processes
P
P012.1 Mendel’s Experiments and the Laws of Probability
p2110.3 Control of the Cell Cycle
p5310.3 Control of the Cell Cycle
P6808.2 The Light-Dependent Reactions of Photosynthesis
P7008.2 The Light-Dependent Reactions of Photosynthesis
Pacinian corpuscles36.2 Somatosensation
pairwise-end sequencing17.3 Whole-Genome Sequencing
Paleognathae29.5 Birds
Paleontology1.2 Themes and Concepts of Biology
palmately compound leaf30.4 Leaves
Pan29.7 The Evolution of Primates
pancreas34.1 Digestive Systems, 37.5 Endocrine Glands
pandemic22.4 Bacterial Diseases in Humans
papillae36.3 Taste and Smell
paracentric13.2 Chromosomal Basis of Inherited Disorders
paracrine signals9.1 Signaling Molecules and Cellular Receptors
parafollicular cells37.5 Endocrine Glands
parapodia28.3 Superphylum Lophotrochozoa
parasite45.6 Community Ecology
parasitic plant31.3 Nutritional Adaptations of Plants
Parasitism24.4 Fungal Parasites and Pathogens
parasympathetic nervous system35.4 The Peripheral Nervous System
parathyroid glands37.5 Endocrine Glands
parathyroid hormone (PTH)37.3 Regulation of Body Processes
Parazoa27.3 Animal Phylogeny
Parenchyma cells30.2 Stems
parent material31.2 The Soil
Parental types13.1 Chromosomal Theory and Genetic Linkage
parietal35.3 The Central Nervous System
Parkinson’s disease35.5 Nervous System Disorders
Parthenogenesis43.1 Reproduction Methods
Partial pressure39.2 Gas Exchange across Respiratory Surfaces
particulate matter39.1 Systems of Gas Exchange
passive immunity42.3 Antibodies
Passive transport5.2 Passive Transport
patella38.1 Types of Skeletal Systems
pathogen-associated molecular patterns (PAMPs)42.1 Innate Immune Response
pathogens21.4 Other Acellular Entities: Prions and Viroids, Introduction
pattern recognition receptors (PRRs)42.1 Innate Immune Response
peat moss25.4 Seedless Vascular Plants
pectoral girdle38.1 Types of Skeletal Systems
pedigree analysis12.2 Characteristics and Traits
pedipalps28.4 Superphylum Ecdysozoa
Peer-reviewed manuscripts1.1 The Science of Biology
pelagic realm44.4 Aquatic Biomes
pellicles23.2 Characteristics of Protists
pelvic girdle38.1 Types of Skeletal Systems
penis43.3 Human Reproductive Anatomy and Gametogenesis
Pepsin34.1 Digestive Systems
pepsinogen34.1 Digestive Systems
peptide bond3.4 Proteins
peptide hormones37.1 Types of Hormones
peptidoglycan22.2 Structure of Prokaryotes
peptidyl transferase15.5 Ribosomes and Protein Synthesis
Perception36.1 Sensory Processes
perforin42.1 Innate Immune Response
perianth26.3 Angiosperms, 32.1 Reproductive Development and Structure
pericardium40.3 Mammalian Heart and Blood Vessels
pericarp32.2 Pollination and Fertilization
pericentric13.2 Chromosomal Basis of Inherited Disorders
pericycle30.3 Roots
periderm30.2 Stems
periodic table2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Peripheral proteins5.1 Components and Structure
peripheral resistance40.4 Blood Flow and Blood Pressure Regulation
perirenal fat capsule41.2 The Kidneys and Osmoregulatory Organs
peristalsis34.1 Digestive Systems
peristome25.3 Bryophytes
peritubular capillary network41.2 The Kidneys and Osmoregulatory Organs
permafrost44.3 Terrestrial Biomes
permanent tissue30.1 The Plant Body
permissive21.2 Virus Infections and Hosts
Peroxisomes4.3 Eukaryotic Cells
Petals26.3 Angiosperms
petiole30.4 Leaves
Petromyzontidae29.2 Fishes
pH scale2.2 Water
phage therapy21.3 Prevention and Treatment of Viral Infections
phagolysosome23.2 Characteristics of Protists
phalanges38.1 Types of Skeletal Systems
Pharmacogenomics17.4 Applying Genomics
Pharyngeal slits29.1 Chordates
pharynx39.1 Systems of Gas Exchange
phenotype12.2 Characteristics and Traits
pheromone36.3 Taste and Smell
Phloem25.4 Seedless Vascular Plants
phosphatases9.3 Response to the Signal
phosphoanhydride bonds6.4 ATP: Adenosine Triphosphate
phosphodiester3.5 Nucleic Acids
phosphodiesterase9.3 Response to the Signal, 37.2 How Hormones Work
Phospholipids3.3 Lipids
Phosphorylation7.1 Energy in Living Systems
photic zone44.4 Aquatic Biomes
photoact8.2 The Light-Dependent Reactions of Photosynthesis
photoautotrophs8.1 Overview of Photosynthesis
Photomorphogenesis30.6 Plant Sensory Systems and Responses
photon8.2 The Light-Dependent Reactions of Photosynthesis
Photoperiodism30.6 Plant Sensory Systems and Responses
photosystem8.2 The Light-Dependent Reactions of Photosynthesis
photosystem I8.2 The Light-Dependent Reactions of Photosynthesis
photosystem II8.2 The Light-Dependent Reactions of Photosynthesis
phototrophs22.1 Prokaryotic Diversity, 22.3 Prokaryotic Metabolism
phototropins30.6 Plant Sensory Systems and Responses
Phototropism30.6 Plant Sensory Systems and Responses
phyllotaxy30.4 Leaves
phylogenetic tree1.2 Themes and Concepts of Biology, 20.1 Organizing Life on Earth
phylogeny20.1 Organizing Life on Earth
phylum20.1 Organizing Life on Earth
physical map17.2 Mapping Genomes
physical sciences1.1 The Science of Biology
physiological dead space39.3 Breathing
phytochromes30.6 Plant Sensory Systems and Responses
pia mater35.3 The Central Nervous System
pigment8.1 Overview of Photosynthesis
pili22.2 Structure of Prokaryotes
pilidium28.3 Superphylum Lophotrochozoa
Pinacocytes28.1 Phylum Porifera
pinna36.4 Hearing and Vestibular Sensation
Pinnately compound leaves30.4 Leaves
pinocytosis5.4 Bulk Transport
pioneer species45.6 Community Ecology
pistil26.3 Angiosperms
pith30.2 Stems
pituitary dwarfism37.3 Regulation of Body Processes
pituitary gland37.5 Endocrine Glands
pituitary stalk37.5 Endocrine Glands
Pivot joints38.3 Joints and Skeletal Movement
placenta43.5 Human Pregnancy and Birth
plagiarism1.1 The Science of Biology
Planar joints38.3 Joints and Skeletal Movement
planktivores44.4 Aquatic Biomes
plankton23.3 Groups of Protists
planospiral28.3 Superphylum Lophotrochozoa
Plantar flexion38.3 Joints and Skeletal Movement
planuliform28.3 Superphylum Lophotrochozoa
plasma40.2 Components of the Blood
plasma cell42.2 Adaptive Immune Response
plasma membrane4.3 Eukaryotic Cells
plasma membrane hormone receptors37.2 How Hormones Work
plasmids15.2 Prokaryotic Transcription
plasmodesmata4.6 Connections between Cells and Cellular Activities
plasmogamy24.1 Characteristics of Fungi
plasmolysis5.2 Passive Transport
plastid23.1 Eukaryotic Origins
platelets40.2 Components of the Blood
Platyrrhini29.7 The Evolution of Primates
Plesiadapis29.7 The Evolution of Primates
pleura39.3 Breathing
Pleurisy39.3 Breathing
plumule32.2 Pollination and Fertilization
Pneumatic bones29.5 Birds
Point mutations14.6 DNA Repair
polar covalent bond2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
polar nuclei32.1 Reproductive Development and Structure
pollen grains26.1 Evolution of Seed Plants
pollen tube26.1 Evolution of Seed Plants
pollination26.4 The Role of Seed Plants, 32.2 Pollination and Fertilization
poly-A tail15.4 RNA Processing in Eukaryotes, 16.5 Eukaryotic Post-transcriptional Gene Regulation
polyandrous45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
Polycarpic32.3 Asexual Reproduction
polygenic17.4 Applying Genomics
Polygynous45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
polymers3.1 Synthesis of Biological Macromolecules
polymorphic28.2 Phylum Cnidaria
polynucleotide3.5 Nucleic Acids
polyp28.2 Phylum Cnidaria
polyploid13.2 Chromosomal Basis of Inherited Disorders
polysaccharide3.2 Carbohydrates
polysome15.5 Ribosomes and Protein Synthesis
polyspermy43.6 Fertilization and Early Embryonic Development
polytomy20.1 Organizing Life on Earth
Pongo29.7 The Evolution of Primates
population1.2 Themes and Concepts of Biology
population density45.1 Population Demography
population genetics19.1 Population Evolution
population growth rate45.3 Environmental Limits to Population Growth
population size (N)45.1 Population Demography
population variation19.2 Population Genetics
Porifera28.1 Phylum Porifera
positive feedback loop33.3 Homeostasis
positive gravitropism30.6 Plant Sensory Systems and Responses
Positive polarity21.1 Viral Evolution, Morphology, and Classification
positive regulator16.2 Prokaryotic Gene Regulation
post-anal tail29.1 Chordates
post-transcriptional16.1 Regulation of Gene Expression
post-translational16.1 Regulation of Gene Expression
posterior pituitary37.5 Endocrine Glands
postzygotic barrier18.2 Formation of New Species
potential energy6.2 Potential, Kinetic, Free, and Activation Energy
potocytosis5.4 Bulk Transport
predators44.4 Aquatic Biomes
preinitiation complex15.3 Eukaryotic Transcription
presbyopia36.5 Vision
prezygotic barrier18.2 Formation of New Species
primary (main) bronchi39.1 Systems of Gas Exchange
Primary active transport5.3 Active Transport
primary consumers46.1 Ecology of Ecosystems
primary electron acceptor8.2 The Light-Dependent Reactions of Photosynthesis
Primary feathers29.5 Birds
primary growth30.2 Stems
primary producers46.1 Ecology of Ecosystems
primary structure3.4 Proteins
primary succession45.6 Community Ecology
primase14.4 DNA Replication in Prokaryotes
Primates29.7 The Evolution of Primates
primer14.4 DNA Replication in Prokaryotes
Prions21.4 Other Acellular Entities: Prions and Viroids
probes17.1 Biotechnology
product rule12.1 Mendel’s Experiments and the Laws of Probability
productive21.2 Virus Infections and Hosts
products2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Progesterone43.4 Hormonal Control of Human Reproduction
prognathic jaws29.7 The Evolution of Primates
progymnosperms26.1 Evolution of Seed Plants
prokaryote4.2 Prokaryotic Cells
Prokaryotes1.2 Themes and Concepts of Biology
prolactin (PRL)37.3 Regulation of Body Processes
prolactin-inhibiting hormone (PIH)37.3 Regulation of Body Processes
prolactin-releasing hormone (PRH)37.3 Regulation of Body Processes
prometaphase10.2 The Cell Cycle
promoter15.2 Prokaryotic Transcription
Pronation38.3 Joints and Skeletal Movement
proofreading14.6 DNA Repair
prophage21.2 Virus Infections and Hosts
prophase10.2 The Cell Cycle
proprioception35.3 The Central Nervous System, 36.1 Sensory Processes
Prosimians29.7 The Evolution of Primates
prostate gland43.3 Human Reproductive Anatomy and Gametogenesis
prosthetic group7.4 Oxidative Phosphorylation
proteases17.1 Biotechnology
proteasome16.6 Eukaryotic Translational and Post-translational Gene Regulation
protein signature17.5 Genomics and Proteomics
Proteins3.4 Proteins
proteome17.5 Genomics and Proteomics
proteomics17.5 Genomics and Proteomics
proto-oncogenes10.4 Cancer and the Cell Cycle
proton2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
protonema25.3 Bryophytes
protonephridia41.3 Excretion Systems
Protostomes27.2 Features Used to Classify Animals
Protraction38.3 Joints and Skeletal Movement
proventriculus34.1 Digestive Systems
proximal convoluted tubule (PCT)41.2 The Kidneys and Osmoregulatory Organs
PrPc21.4 Other Acellular Entities: Prions and Viroids
PrPsc21.4 Other Acellular Entities: Prions and Viroids
pseudocoelomates27.2 Features Used to Classify Animals
pseudopeptidoglycan22.2 Structure of Prokaryotes
pseudostratified33.2 Animal Primary Tissues
pulmocutaneous circulation40.1 Overview of the Circulatory System
pulmonary circulation40.1 Overview of the Circulatory System
pumps5.3 Active Transport
punctuated equilibrium18.3 Reconnection and Rates of Speciation
Punnett square12.2 Characteristics and Traits
pure culture17.4 Applying Genomics
purines3.5 Nucleic Acids
pyrimidines3.5 Nucleic Acids
pyruvate7.2 Glycolysis
Q
quadrat45.1 Population Demography
quaternary structure3.4 Proteins
quiescent10.2 The Cell Cycle
quorum sensing9.4 Signaling in Single-Celled Organisms
R
r-selected species45.4 Population Dynamics and Regulation
radial27.2 Features Used to Classify Animals
Radial glia35.1 Neurons and Glial Cells
Radial symmetry27.2 Features Used to Classify Animals
radiate arteries41.2 The Kidneys and Osmoregulatory Organs
Radiation hybrid mapping17.2 Mapping Genomes
radicle32.2 Pollination and Fertilization
radioisotopes2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
radioresistant22.1 Prokaryotic Diversity
radius38.1 Types of Skeletal Systems
radula28.3 Superphylum Lophotrochozoa
raphe23.3 Groups of Protists
reactants2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
reaction center8.2 The Light-Dependent Reactions of Photosynthesis
reading frame15.1 The Genetic Code
reception36.1 Sensory Processes
receptive36.1 Sensory Processes
receptor potential36.1 Sensory Processes
receptor-mediated endocytosis5.4 Bulk Transport
receptors9.1 Signaling Molecules and Cellular Receptors, 37.2 How Hormones Work
recessive lethal12.2 Characteristics and Traits
Recessive traits12.1 Mendel’s Experiments and the Laws of Probability
reciprocal cross12.1 Mendel’s Experiments and the Laws of Probability
recombinant DNA17.1 Biotechnology
recombinant proteins17.1 Biotechnology
recombination frequency13.1 Chromosomal Theory and Genetic Linkage
recombination nodules11.1 The Process of Meiosis
recruitment39.3 Breathing
rectum34.1 Digestive Systems
Red blood cells40.2 Components of the Blood
redox reactions7.1 Energy in Living Systems
reduction8.3 Using Light Energy to Make Organic Molecules
reduction division11.1 The Process of Meiosis
reflex action45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
refractory period35.2 How Neurons Communicate
regulatory T (Treg) cells42.2 Adaptive Immune Response
reinforcement18.3 Reconnection and Rates of Speciation
relative fitness19.3 Adaptive Evolution
Relative species abundance45.6 Community Ecology
renal arteries41.2 The Kidneys and Osmoregulatory Organs
renal capsule41.2 The Kidneys and Osmoregulatory Organs
renal columns41.2 The Kidneys and Osmoregulatory Organs
renal corpuscle41.2 The Kidneys and Osmoregulatory Organs
renal fascia41.2 The Kidneys and Osmoregulatory Organs
renal pelvis41.2 The Kidneys and Osmoregulatory Organs
renal pyramids41.2 The Kidneys and Osmoregulatory Organs
renal tubule41.2 The Kidneys and Osmoregulatory Organs
renal veins41.2 The Kidneys and Osmoregulatory Organs
renin37.3 Regulation of Body Processes
renin-angiotensin-aldosterone41.5 Hormonal Control of Osmoregulatory Functions
replication forks14.4 DNA Replication in Prokaryotes
replicative intermediates21.1 Viral Evolution, Morphology, and Classification
Repressors16.2 Prokaryotic Gene Regulation
Reproductive cloning17.1 Biotechnology
reproductive isolation18.2 Formation of New Species
Residence time46.3 Biogeochemical Cycles
residual volume (RV)39.2 Gas Exchange across Respiratory Surfaces
resilience46.1 Ecology of Ecosystems
resistance39.3 Breathing, 46.1 Ecology of Ecosystems
respiratory bronchioles39.1 Systems of Gas Exchange
respiratory distress syndrome39.3 Breathing
respiratory quotient (RQ)39.2 Gas Exchange across Respiratory Surfaces
respiratory rate39.3 Breathing
Restriction endonucleases17.1 Biotechnology
restriction fragment length polymorphisms17.2 Mapping Genomes
restrictive diseases39.3 Breathing
results1.1 The Science of Biology
resuscitation22.1 Prokaryotic Diversity
retina36.5 Vision
retinoblastoma protein (Rb)10.3 Control of the Cell Cycle
Retraction38.3 Joints and Skeletal Movement
reverse transcriptase21.1 Viral Evolution, Morphology, and Classification
reverse transcriptase PCR (RT-PCR)17.1 Biotechnology
Reversible reactions2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
Review articles1.1 The Science of Biology
rhizobia31.3 Nutritional Adaptations of Plants
rhizoids25.3 Bryophytes
rhizome30.2 Stems
rhizosphere31.2 The Soil
Rho-dependent termination15.2 Prokaryotic Transcription
Rho-independent termination15.2 Prokaryotic Transcription
rhodopsin36.5 Vision
rhynchocoel28.3 Superphylum Lophotrochozoa
ribonucleases17.1 Biotechnology
ribonucleic acid (RNA)3.5 Nucleic Acids
Ribosomal RNA (rRNA)3.5 Nucleic Acids
Ribosomes4.3 Eukaryotic Cells
ribs38.1 Types of Skeletal Systems
ring of life20.3 Perspectives on the Phylogenetic Tree
RNA editing15.4 RNA Processing in Eukaryotes
RNA-binding proteins16.5 Eukaryotic Post-transcriptional Gene Regulation
RNA-induced silencing complex (RISC)16.5 Eukaryotic Post-transcriptional Gene Regulation
RNAs15.3 Eukaryotic Transcription
rods36.5 Vision
root cap30.3 Roots
Root hairs30.3 Roots
root system30.1 The Plant Body
rooted20.1 Organizing Life on Earth
Rotational movement38.3 Joints and Skeletal Movement
rough endoplasmic reticulum (RER)4.4 The Endomembrane System and Proteins
roughage34.1 Digestive Systems
Ruffini endings36.2 Somatosensation
Ruminants34.1 Digestive Systems
Runners30.2 Stems
S
S phase10.2 The Cell Cycle
S-layer22.2 Structure of Prokaryotes
S-shaped curve45.3 Environmental Limits to Population Growth
Saddle joints38.3 Joints and Skeletal Movement
sagittal plane33.1 Animal Form and Function
Salamanders29.3 Amphibians
salivary amylase34.1 Digestive Systems
saltatory conduction35.2 How Neurons Communicate
sand31.2 The Soil
saprobes24.1 Characteristics of Fungi
saprophyte31.3 Nutritional Adaptations of Plants
sarcolemma38.4 Muscle Contraction and Locomotion
sarcomeres38.4 Muscle Contraction and Locomotion
Sarcopterygii29.2 Fishes
Sargassum44.4 Aquatic Biomes
Satellite glia35.1 Neurons and Glial Cells
saturated fatty acid3.3 Lipids
Sauropsids29.4 Reptiles
scapulae38.1 Types of Skeletal Systems
Scarification32.2 Pollination and Fertilization
schizocoelom28.3 Superphylum Lophotrochozoa
schizocoely27.2 Features Used to Classify Animals
Schizophrenia35.5 Nervous System Disorders
Schwann cell35.1 Neurons and Glial Cells
Science1.1 The Science of Biology
scientific method1.1 The Science of Biology
scion32.3 Asexual Reproduction
Sclerenchyma cells30.2 Stems
sclerocytes28.1 Phylum Porifera
scrotum43.3 Human Reproductive Anatomy and Gametogenesis
scutellum32.2 Pollination and Fertilization
Sebaceous glands29.6 Mammals
Second messengers9.2 Propagation of the Signal
Secondary active transport5.3 Active Transport
Secondary consumers46.1 Ecology of Ecosystems
Secondary feathers29.5 Birds
Secondary growth30.2 Stems
secondary plant compounds47.2 The Importance of Biodiversity to Human Life
secondary structure3.4 Proteins
secondary succession45.6 Community Ecology
secretin34.4 Digestive System Regulation
seed26.1 Evolution of Seed Plants
seedless25.1 Early Plant Life
Seedless non-vascular plants25.1 Early Plant Life
segmental arteries41.2 The Kidneys and Osmoregulatory Organs
selection pressure19.2 Population Genetics
selectively permeable5.2 Passive Transport
Self-pollination32.2 Pollination and Fertilization
Semelparity45.2 Life Histories and Natural Selection
Semen43.3 Human Reproductive Anatomy and Gametogenesis
semi-permeable membranes41.1 Osmoregulation and Osmotic Balance
semicircular canals36.4 Hearing and Vestibular Sensation
semilunar valve40.3 Mammalian Heart and Blood Vessels
seminal vesicles43.3 Human Reproductive Anatomy and Gametogenesis
seminiferous tubules43.3 Human Reproductive Anatomy and Gametogenesis
senescence32.3 Asexual Reproduction
sensory receptor36.1 Sensory Processes
sensory transduction36.1 Sensory Processes
sensory-somatic nervous system35.4 The Peripheral Nervous System
sepals26.3 Angiosperms
septa24.1 Characteristics of Fungi
septum10.5 Prokaryotic Cell Division, 24.1 Characteristics of Fungi
Sequence mapping 17.2 Mapping Genomes
serendipity1.1 The Science of Biology
serotype22.4 Bacterial Diseases in Humans
Sertoli cells43.4 Hormonal Control of Human Reproduction
serum40.2 Components of the Blood
Sesamoid bones38.2 Bone
sessile30.4 Leaves
set point33.3 Homeostasis
seta25.3 Bryophytes
setae/chaetae28.3 Superphylum Lophotrochozoa
sexual dimorphisms19.3 Adaptive Evolution
sexual reproduction43.1 Reproduction Methods
shared ancestral character20.2 Determining Evolutionary Relationships
shared derived character20.2 Determining Evolutionary Relationships
Shine-Dalgarno sequence15.5 Ribosomes and Protein Synthesis
shoot system30.1 The Plant Body
Short bones38.2 Bone
shotgun sequencing17.3 Whole-Genome Sequencing
sickle cell anemia39.4 Transport of Gases in Human Bodily Fluids
sieve-tube cells30.2 Stems
signal integration9.2 Propagation of the Signal
signal sequence15.5 Ribosomes and Protein Synthesis
signal transduction9.2 Propagation of the Signal
signaling cells9.1 Signaling Molecules and Cellular Receptors
signaling pathway9.2 Propagation of the Signal
signals45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
silent mutations14.6 DNA Repair
silt31.2 The Soil
simple epithelia33.2 Animal Primary Tissues
simple fruit32.2 Pollination and Fertilization
simple leaf30.4 Leaves
simulation model46.1 Ecology of Ecosystems
single nucleotide polymorphisms17.2 Mapping Genomes
Single-strand binding proteins14.4 DNA Replication in Prokaryotes
sinks30.5 Transport of Water and Solutes in Plants
sinoatrial (SA) node40.3 Mammalian Heart and Blood Vessels
siphonophore28.2 Phylum Cnidaria
sister taxa20.1 Organizing Life on Earth
Skeletal muscle tissue38.4 Muscle Contraction and Locomotion
skull38.1 Types of Skeletal Systems
sliding clamp14.4 DNA Replication in Prokaryotes
small intestine34.1 Digestive Systems
small nuclear 15.3 Eukaryotic Transcription
smooth endoplasmic reticulum (SER)4.4 The Endomembrane System and Proteins
Smooth muscle tissue38.4 Muscle Contraction and Locomotion
Soil31.2 The Soil
soil profile31.2 The Soil
Solar intensity44.5 Climate and the Effects of Global Climate Change
solute5.2 Passive Transport
solutes5.2 Passive Transport
solvent2.2 Water
somatic cell11.1 The Process of Meiosis
somatosensation35.3 The Central Nervous System
somatostatin34.4 Digestive System Regulation
somites43.7 Organogenesis and Vertebrate Formation
soredia24.3 Ecology of Fungi
source water44.4 Aquatic Biomes
sources30.5 Transport of Water and Solutes in Plants
Southern blotting17.1 Biotechnology
speciation18.2 Formation of New Species
species18.2 Formation of New Species, 20.1 Organizing Life on Earth
Species dispersion patterns45.1 Population Demography
Species richness45.6 Community Ecology
species-area relationship47.1 The Biodiversity Crisis
specific heat capacity2.2 Water
spectrophotometer8.2 The Light-Dependent Reactions of Photosynthesis
spermatheca43.2 Fertilization
spermatogenesis43.3 Human Reproductive Anatomy and Gametogenesis
spermatophytes26.1 Evolution of Seed Plants
Sphenodontia29.4 Reptiles
sphere of hydration2.2 Water
sphincter34.1 Digestive Systems
spicules28.1 Phylum Porifera
spinal cord35.3 The Central Nervous System
Spinal nerves35.4 The Peripheral Nervous System
spiral cleavage27.2 Features Used to Classify Animals
spirometry39.2 Gas Exchange across Respiratory Surfaces
splicing15.4 RNA Processing in Eukaryotes
spongocoel28.1 Phylum Porifera
spongy bone38.2 Bone
Spontaneous mutations14.6 DNA Repair
sporangium24.1 Characteristics of Fungi
Spores11.1 The Process of Meiosis, Introduction
sporocytes25.1 Early Plant Life
sporophylls25.4 Seedless Vascular Plants
sporophyte11.2 Sexual Reproduction, 32.1 Reproductive Development and Structure
sporopollenin25.1 Early Plant Life
spring and fall turnover44.2 Biogeography
Squamata29.4 Reptiles
Squamous epithelial33.2 Animal Primary Tissues
stabilizing selection19.3 Adaptive Evolution
stamens26.3 Angiosperms
standard metabolic rate (SMR)33.1 Animal Form and Function
stapes36.4 Hearing and Vestibular Sensation
starch3.2 Carbohydrates
start codon15.5 Ribosomes and Protein Synthesis
statoliths30.6 Plant Sensory Systems and Responses
stele30.3 Roots
stereocilia36.4 Hearing and Vestibular Sensation
stereoscopic vision29.7 The Evolution of Primates
sternum38.1 Types of Skeletal Systems
steroids3.3 Lipids
stigma26.3 Angiosperms
stipules30.4 Leaves
Stolons30.2 Stems
stomach34.1 Digestive Systems
stomata8.1 Overview of Photosynthesis
stratified epithelia33.2 Animal Primary Tissues
Streptophyta25.2 Green Algae: Precursors of Land Plants
Strigolactones30.6 Plant Sensory Systems and Responses
Strobili25.4 Seedless Vascular Plants
strobilus26.2 Gymnosperms
stroke volume40.4 Blood Flow and Blood Pressure Regulation
stroma8.1 Overview of Photosynthesis
stromatolite22.1 Prokaryotic Diversity
Structural isomers2.3 Carbon
style26.3 Angiosperms
subduction46.3 Biogeochemical Cycles
substituted hydrocarbons2.3 Carbon
substrate-level phosphorylation7.1 Energy in Living Systems
substrates6.5 Enzymes
sucrases34.3 Digestive System Processes
sulci35.3 The Central Nervous System
sum rule12.1 Mendel’s Experiments and the Laws of Probability
summation35.2 How Neurons Communicate
superior colliculus36.5 Vision
superior vena cava40.3 Mammalian Heart and Blood Vessels
Supination38.3 Joints and Skeletal Movement
suprachiasmatic nucleus36.5 Vision
surface tension2.2 Water
Surfactant39.3 Breathing
survivorship curve45.1 Population Demography
suspensor32.2 Pollination and Fertilization
Sutural bones38.2 Bone
Sutures38.3 Joints and Skeletal Movement
swim bladder29.2 Fishes
symbiont31.3 Nutritional Adaptations of Plants
symbioses45.6 Community Ecology
sympathetic nervous system35.4 The Peripheral Nervous System
Sympatric speciation18.2 Formation of New Species
symphyses38.3 Joints and Skeletal Movement
symporter5.3 Active Transport
synapses35.1 Neurons and Glial Cells
Synapsids29.4 Reptiles
synapsis11.1 The Process of Meiosis
synaptic cleft35.2 How Neurons Communicate
synaptic signal9.1 Signaling Molecules and Cellular Receptors
synaptic vesicles35.2 How Neurons Communicate
synaptonemal complex11.1 The Process of Meiosis
synarthrosis38.3 Joints and Skeletal Movement
synchondrosis38.3 Joints and Skeletal Movement
Syndesmoses38.3 Joints and Skeletal Movement
synergid32.1 Reproductive Development and Structure
Synovial joints38.3 Joints and Skeletal Movement
system34.4 Digestive System Regulation
systematics20.1 Organizing Life on Earth
systemic circulation40.1 Overview of the Circulatory System
Systems biology17.5 Genomics and Proteomics
systole40.3 Mammalian Heart and Blood Vessels
T
T cells42.1 Innate Immune Response
Tachyglossidae29.6 Mammals
tadpole29.3 Amphibians
tap root system30.3 Roots
target cells9.1 Signaling Molecules and Cellular Receptors
tarsals38.1 Types of Skeletal Systems
tastants36.3 Taste and Smell
taste bud36.3 Taste and Smell
taxis45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
taxon20.1 Organizing Life on Earth
Taxonomy20.1 Organizing Life on Earth
TCA cycle7.3 Oxidation of Pyruvate and the Citric Acid Cycle
tectorial membrane36.4 Hearing and Vestibular Sensation
tegmen32.2 Pollination and Fertilization
teichoic acids