Student Resources

Activities

• Activity 1.1 The Hierarchy of Biological Organization
• Activity 2.1 Electron Orbitals
• Activity 3.1 Functional Groups
• Activity 3.2 Features of Amino Acids
• Activity 3.3 Forms of Glucose
• Activity 3.4 Macromolecule Building Simulation
• Activity 4.1 Nucleic Acid Building Blocks
• Activity 4.2 DNA Structure
• Activity 5.1 The Scale of Life
• Activity 5.2 Know Your Techniques
• Activity 5.3 Eukaryotic Cell Tour
• Activity 5.4 Lysosomal Digestion
• Activity 6.1 The Fluid Mosaic Model
• Activity 6.2 Lipid Bilayer Composition Simulation
• Activity 6.3 Animal Cell Junctions
• Activity 6.4 Membrane Transport Simulation
• Activity 7.1 Chemical Signaling Systems
• Activity 7.2 Cell Signaling and Amplification Simulation
• Activity 7.3 Concept Matching: Signaling in Cells
• Activity 8.1 ATP and Coupled Reactions
• Activity 8.2 Free Energy Changes
• Activity 8.3 System Simulation
• Activity 9.1 Glycolysis and Fermentation
• Activity 9.2 Energy Pathways in Cells
• Activity 9.3 The Citric Acid Cycle
• Activity 9.4 Respiratory Chain
• Activity 9.5 Electron Transport Chain Building Simulation
• Activity 9.6 Energy Levels
• Activity 9.7 Regulation of Energy Pathways
• Activity 10.1 The Calvin Cycle
• Activity 10.2 C₃ and C₄ Leaf Anatomy
• Activity 11.1 Images of Mitosis
• Activity 11.2 The Mitotic Spindle
• Activity 11.3 Sexual Life Cycle
• Activity 11.4 Meiosis Simulation
• Activity 11.5 Images of Meiosis
• Activity 12.1 Homozygous or Heterozygous?
• Activity 12.2 Pedigree Analysis Simulation
• Activity 12.3 Concept Matching: Inheritance, Genes, and Chromosomes
• Activity 13.1 The Replication Complex
• Activity 13.2 Polymerase Chain Reaction Simulation
• Activity 14.1 Eukaryotic Gene Expression
• Activity 14.2 The Genetic Code
• Activity 15.1 Mutations and Function Simulation
• Activity 15.2 Point Mutations Simulation
• Activity 15.3 Allele-Specific Cleavage
• Activity 16.1 Eukaryotic Gene Expression Control Points
• Activity 16.2 Concept Matching: Gene Expression
• Activity 17.1 Concept Matching: Genomes
• Activity 18.1 CRISPR Simulation
• Activity 18.2 Expression Vectors
• Activity 19.1 Stages of Development
• Activity 19.2 Cell Fates Simulation
• Activity 19.3 Genes and Development Simulation
• Activity 20.1 Darwin's Voyage
• Activity 20.2 Natural Selection Simulation
• Activity 20.3 Genetic Drift Simulation
• Activity 20.4 Hardy-Weinberg Equilibrium
• Activity 21.1 Constructing a Phylogenetic Tree
• Activity 21.2 Phylogeny and Molecular Evolution Simulation
• Activity 21.3 Types of Taxa
• Activity 22.1 Speciation Simulation
• Activity 22.2 Concept Matching: Speciation
• Activity 23.1 Amino Acid Sequence Alignment
• Activity 23.2 Similarity Matrix Construction
• Activity 23.3 Gene Tree Construction
• Activity 24.1 Concept Matching: The History of Life
• Activity 25.1 Gram Stain and Bacteria
• Activity 26.1 Anatomy of Paramecium
• Activity 27.1 The Fern Life Cycle
• Activity 27.2 Homospory
• Activity 27.3 Heterospory
• Activity 28.1 Flower Morphology
• Activity 28.2 Life Cycle of a Conifer
• Activity 29.1 Fungal Phylogeny
• Activity 29.2 Life Cycle of a Dikaryotic Fungus
• Activity 30.1 Animal Body Cavities
• Activity 30.2 Sponge and Diploblast Classification
• Activity 30.3 Diversity Simulation
• Activity 31.1 Features of the Protostomes
• Activity 31.2 Protostome Classification
• Activity 32.1 Deuterostome Phylogeny
• Activity 32.2 The Amniote Egg
• Activity 32.3 Deuterostome Classification
• Activity 32.4 The Major Groups of Organisms
• Activity 33.1 Eudicot Root
• Activity 33.2 Monocot Root
• Activity 33.3 Eudicot Stem
• Activity 33.4 Monocot Stem
• Activity 33.5 Eudicot Leaf
• Activity 34.1 Water Uptake in Plants
• Activity 34.2 Apoplast and Symplast of the Root
• Activity 35.1 Concept Matching: Plant Nutrition
• Activity 36.1 Monocot Shoot Development
• Activity 36.2 Eudicot Shoot Development
• Activity 36.3 Events of Seed Germination
• Activity 37.1 Sexual Reproduction in Angiosperms
• Activity 37.2 Flowering and Day Length Simulation
• Activity 38.1 Plant Defenses Simulation
• Activity 38.2 Concept Matching: Plant Adaptations
• Activity 39.1 Tissues and Cell Types
• Activity 39.2 Temperature Regulation System Simulation
• Activity 39.3 Thermoregulation in an Endotherm
• Activity 40.1 The Human Endocrine Glands
• Activity 40.2 Concept Matching: Vertebrate Hormones
• Activity 41.1 The Human Defense System
• Activity 41.2 Cells of the Immune System
• Activity 41.3 Inflammatory Response
• Activity 41.4 Immunoglobulin Structure
• Activity 42.1 The Human Male Reproductive Tract
• Activity 42.2 Spermatogenesis
• Activity 42.3 The Human Female Reproductive Tract
• Activity 43.1 Extraembryonic Membranes
• Activity 44.1 Neurons and Synapses Simulation
• Activity 44.2 Neurotransmitters
• Activity 45.1 Structures of the Human Ear
• Activity 45.2 Mechanoreceptors Simulation
• Activity 45.3 Structure of the Human Eye
• Activity 45.4 Structure of the Human Retina
• Activity 46.1 The Human Cerebrum
• Activity 46.2 Visual Receptive Fields Simulation
• Activity 46.3 Language Areas of the Cortex
• Activity 46.4 Concept Matching: The Mammalian Nervous System
• Activity 47.1 The Structure of a Sarcomere
• Activity 47.2 The Neuromuscular Junction
• Activity 47.3 Joints
• Activity 48.1 The Human Respiratory System
• Activity 48.2 Hemoglobin Loading Simulation
• Activity 48.3 Oxygen-Binding Curves
• Activity 48.4 Concept Matching: Gas Exchange
• Activity 49.1 Vertebrate Circulatory Systems
• Activity 49.2 The Human Heart
• Activity 49.3 Structure of Blood Vessels
• Activity 49.4 Blood Pressure and Heart Rate Simulation
• Activity 50.1 Mineral Elements Required by Animals
• Activity 50.2 Vitamins in the Human Diet
• Activity 50.3 Mammalian Teeth
• Activity 50.4 The Human Digestive System
• Activity 50.5 Parabiotic Mice Simulation
• Activity 51.1 Annelid Metanephridia
• Activity 51.2 The Vertebrate Nephron
• Activity 51.3 The Human Excretory System
• Activity 51.4 Kidney Regulation Simulation
• Activity 51.5 The Major Organ Systems
• Activity 52.1 Homing Simulation
• Activity 52.2 Honey Bee Dance Communication
• Activity 52.3 Concept Matching: Animal Behavior
• Activity 53.1 Biomes
• Activity 53.2 Aquatic Biomes
• Activity 53.3 Major Biogeographic Regions
• Activity 53.4 Biogeography Simulation
• Activity 54.1 Exponential Population Growth Simulation
• Activity 54.2 Logistic Population Growth
• Activity 54.3 Logistic Population Growth Simulation
• Activity 54.4 Age Structure and Survivorship Simulation
• Activity 54.5 Metapopulation Simulation
• Activity 55.1 Ecological Interactions
• Activity 55.2 Coevolution Simulation
• Activity 55.3 Predator-Prey System Simulation
• Activity 56.1 The Major Trophic Levels
• Activity 56.2 Measures of Species Diversity
• Activity 57.1 Energy Flow through an Ecosystem
• Activity 57.2 Concept Matching: Ecosystems
• Activity 58.1 Concept Matching: A Changing Biosphere
• Activity B1 Standard Deviations, Standard Errors, and Confidence Intervals Simulation

Animations

• Animation 1.1 Using Scientific Methodology
• Animation 2.1 Chemical Bond Formation
• Animation 3.1 Proteins, Carbohydrates, and Lipids
• Animation 4.1 Nucleic Acids
• Animation 4.2 Pasteur's Experiment
• Animation 4.3 Synthesis of Prebiotic Molecules
• Animation 5.1 The Golgi Apparatus
• Animation 6.1 Passive Transport
• Animation 6.2 Active Transport
• Animation 6.3 Endocytosis and Exocytosis
• Animation 7.1 A Signal Transduction Pathway
• Animation 7.2 Signal Transduction and Cancer
• Animation 8.1 Enzyme Catalysis
• Animation 8.2 Allosteric Regulation of Enzymes
• Animation 9.1 Electron Transport and ATP Synthesis
• Animation 9.2 Two Experiments Demonstrate the Chemiosmotic Mechanism
• Animation 10.1 The Source of the Oxygen Produced by Photosynthesis
• Animation 10.2 Photophosphorylation
• Animation 10.3 Tracing the Pathway of CO₂
• Animation 11.1 Mitosis
• Animation 11.2 Meiosis
• Animation 12.1 Independent Assortment of Alleles
• Animation 12.2 Alleles That Do Not Assort Independently
• Animation 13.1 The Hershey-Chase Experiment
• Animation 13.2 DNA Replication and Polymerization
• Animation 13.3 The Meselson–Stahl Experiment
• Animation 13.4 Leading and Lagging Strand Synthesis
• Animation 14.1 Transcription
• Animation 14.2 Deciphering the Genetic Code
• Animation 14.3 RNA Splicing
• Animation 14.4 Translation
• Animation 15.1 Gel Electrophoresis
• Animation 15.2 DNA Testing
• Animation 16.1 The lac Operon
• Animation 16.2 The trp Operon
• Animation 16.3 Initiation of Transcription
• Animation 17.1 Sequencing the Genome
• Animation 17.2 High-Throughput Sequencing
• Animation 18.1 DNA Microarray Technology
• Animation 19.1 Embryonic Stem Cells
• Animation 19.2 Early Asymmetry in the Embryo
• Animation 19.3 Pattern Formation in the Drosophila Embryo
• Animation 19.4 Modularity
• Animation 20.1 Natural Selection
• Animation 20.2 Assessing the Costs of Adaptation
• Animation 21.1 Using Phylogenetic Analysis to Reconstruct Evolutionary History
• Animation 22.1 Speciation Mechanisms
• Animation 22.2 Founder Events and Allopatric Speciation
• Animation 23.1 Concerted Evolution
• Animation 24.1 Movement of the Continents
• Animation 25.1 The Evolution of the Three Domains
• Animation 26.1 Family Tree of Chloroplasts
• Animation 26.2 Digestive Vacuoles
• Animation 26.3 The Life Cycle of the Malarial Parasite
• Animation 27.1 Life Cycle of a Moss
• Animation 28.1 Life Cycle of a Conifer
• Animation 28.2 Life Cycle of an Angiosperm
• Animation 29.1 Life Cycle of a Zygospore Fungus
• Animation 30.1 Life Cycle of a Cnidarian
• Animation 31.1 An Overview of the Protostomes
• Animation 32.1 An Overview of the Deuterostomes
• Animation 32.2 Life Cycle of a Frog
• Animation 33.1 Secondary Growth: The Vascular Cambium
• Animation 34.1 Xylem Transport
• Animation 34.2 The Pressure Flow Model
• Animation 35.1 Nitrogen and Iron Deficiencies
• Animation 36.1 Tropisms
• Animation 36.2 Went’s Experiment
• Animation 36.3 Auxin Affects Cell Walls
• Animation 37.1 Double Fertilization
• Animation 37.2 The Effect of Interrupted Days and Nights
• Animation 38.1 Signaling between Plants and Pathogens
• Animation 39.1 The Hypothalamus
• Animation 40.1 The Hypothalamic–Pituitary–Endocrine Axis
• Animation 40.2 Complete Metamorphosis
• Animation 40.3 Hormonal Regulation of Calcium
• Animation 41.1 Pregnancy Test
• Animation 41.2 Humoral Immune Response
• Animation 41.3 A B Cell Builds an Antibody
• Animation 41.4 Cellular Immune Response
• Animation 42.1 Fertilization in a Sea Urchin Egg
• Animation 42.2 The Ovarian and Uterine Cycles
• Animation 43.1 Gastrulation
• Animation 43.2 The Primary Embryonic Organizer
• Animation 44.1 The Resting Membrane Potential
• Animation 44.2 The Action Potential
• Animation 44.3 Synaptic Transmission
• Animation 44.4 Information Processing in the Spinal Cord
• Animation 45.1 Sound Transduction in the Human Ear
• Animation 45.2 Photosensitivity
• Animation 46.1 Information Processing in the Retina
• Animation 47.1 Molecular Mechanisms of Muscle Contraction
• Animation 47.2 Smooth Muscle Action
• Animation 48.1 Airflow in Birds
• Animation 48.2 Airflow in Mammals
• Animation 49.1 The Cardiac Cycle
• Animation 50.1 The Digestion and Absorption of Fats
• Animation 50.2 Insulin and Glucose Regulation
• Animation 51.1 The Mammalian Kidney
• Animation 52.1 The Costs of Defending a Territory
• Animation 52.2 Foraging Behavior
• Animation 52.3 Circadian Rhythms
• Animation 52.4 Time-Compensated Solar Compass
• Animation 53.1 Radiant Energy Balance
• Animation 53.2 Rain Shadow
• Animation 53.3 Island Biogeography in the Florida Keys
• Animation 53.4 Edge Effects
• Animation 54.1 The Mark-Recapture Method
• Animation 55.1 Mutualism
• Animation 56.1 Primary Succession on a Glacial Moraine
• Animation 57.1 The Global Hydrologic Cycle
• Animation 57.2 The Global Carbon Cycle
• Animation 57.3 The Global Nitrogen Cycle
• Animation 58.1 The Effects of Climate Change

Media Clips

• Media Clip 1.1 Leaping Lemurs
• Media Clip 2.1 The Elements Song
• Media Clip 3.1 Protein Structures in 3D
• Media Clip 4.1 DNA Building Blocks from Space
• Media Clip 5.1 The Inner Life of a Cell
• Media Clip 6.1 An Amoeba Eats by Phagocytosis
• Media Clip 7.1 Social Amoebas Aggregate on Cue
• Media Clip 8.1 Bioluminescence in the Deep Sea
• Media Clip 9.1 ATP Synthase in Motion
• Media Clip 10.1 Chloroplasts in Close-Up
• Media Clip 11.1 Mitosis: Live and Up Close
• Media Clip 12.1 Mendel's Discoveries
• Media Clip 13.1 Discovery of the Double Helix
• Media Clip 14.1 Protein Synthesis: An Epic on a Cellular Level
• Media Clip 15.1 Sickle Cells: Deformed by a Mutation
• Media Clip 16.1 The Surprising Epigenetics of Identical Twins
• Media Clip 17.1 A Big Surprise from Genomics
• Media Clip 18.1 Striking Views of Recombinant DNA Being Made
• Media Clip 19.1 Spectacular Fly Development in 3D
• Media Clip 20.1 Watching Evolution in Real Time
• Media Clip 20.2 A. luna in Flight
• Media Clip 20.3 Big Brown Bats (E. fuscus) versus A. luna
• Media Clip 20.4 Human Echolocation
• Media Clip 21.1 Morphing Arachnids
• Media Clip 22.1 Narrowmouth Toads Calling for Mates
• Media Clip 23.1 The Ubiquitous Protein
• Media Clip 24.1 The Age of the Earth
• Media Clip 24.2 Lava Flows and Magma Explosions
• Media Clip 25.1 Cyanobacteria
• Media Clip 25.2 A Swarm of Salmonella
• Media Clip 25.3 Bacteriophages Attack E. coli
• Media Clip 26.1 A Dinoflagellate Shows Off Its Flagellum
• Media Clip 26.2 Diatoms in Action
• Media Clip 26.3 A Kelp Forest
• Media Clip 26.4 Euglenids
• Media Clip 26.5 Amoeboid Movement
• Media Clip 26.6 Plasmodial Slime Mold Growth
• Media Clip 26.7 Cellular Slime Mold Aggregation
• Media Clip 26.8 Flashing Dinoflagellates
• Media Clip 27.1 Reproductive Structures of Stoneworts
• Media Clip 27.2 Nonvascular Plant Reproduction
• Media Clip 27.3 Liverwort Life Cycle
• Media Clip 28.1 Pollen Transfer by Wind
• Media Clip 28.2 Pollen Transfer by a Bat
• Media Clip 28.3 Flower and Fruit Formation
• Media Clip 29.1 Fungal Decomposers
• Media Clip 29.2 Mind-Control Killer Fungi
• Media Clip 29.3 Time Lapse of Beer Fermentation
• Media Clip 30.1 Nervous Systems Lead to Efficient Predators
• Media Clip 30.2 Filter Feeders
• Media Clip 30.3 Detritivores
• Media Clip 30.4 Ctenophores
• Media Clip 30.5 Stunning Siphonophore: Colonial Hydrozoans
• Media Clip 31.1 Feeding with a Lophophore
• Media Clip 31.2 Molting a Cuticle
• Media Clip 31.3 Rotifer Feeding
• Media Clip 31.4 Explosive Extrusion of Ribbon Worm Proboscis
• Media Clip 31.5 Leeches Feeding on Blood
• Media Clip 31.6 Octopuses Can Pass Through Small Openings
• Media Clip 31.7 Barnacles Feeding
• Media Clip 31.8 Complete Metamorphosis
• Media Clip 32.1 Sea Star Hunting Bivalves
• Media Clip 32.2 Hagfish Slime
• Media Clip 32.3 Coelacanths in the Deep Seas
• Media Clip 32.4 Answering a Mating Call
• Media Clip 32.5 Komodo Dragons Bring Down Prey
• Media Clip 32.6 Falcons in Flight
• Media Clip 32.7 Bats Feeding in Flight
• Media Clip 33.1 Rapid Growth of Brambles
• Media Clip 33.2 Cell Expansion in Root Hairs
• Media Clip 34.1 Inside the Xylem
• Media Clip 35.1 A Venus Flytrap "Snaps to It"
• Media Clip 36.1 Gibberellin Binding to Its Receptor
• Media Clip 37.1 Pollen Germination in Real Time
• Media Clip 37.2 How Plants Remember
• Media Clip 38.1 Plants Can Hear Danger
• Media Clip 38.2 Leaves for Every Environment
• Media Clip 39.1 Thermoregulation in Animals
• Media Clip 40.1 The Testosterone Factor
• Media Clip 41.1 The Chase Is On: Phagocyte versus Bacteria
• Media Clip 42.1 Human Ovulation
• Media Clip 43.1 Frog Gastrulation Time-Lapse
• Media Clip 44.1 Put Some ACh Into It!
• Media Clip 45.1 Into the Eye
• Media Clip 46.1 The Man with No Short-Term Memory
• Media Clip 47.1 Be Still My Beating Stem Cell Heart
• Media Clip 48.1 Sea Bed Hunting on One Breath
• Media Clip 49.1 Capillary Flow: A Tight Squeeze
• Media Clip 50.1 Following Food from Mouth to Gut
• Media Clip 51.1 Inside the Bladder
• Media Clip 52.1 Social Shrimps
• Media Clip 53.1 Rafting to Madagascar
• Media Clip 54.1 World Population Growth
• Media Clip 55.1 Bombardier Beetle Sprays Its Enemies
• Media Clip 55.2 Lionfish "Strike" Again!
• Media Clip 56.1 A Food Web in Africa
• Media Clip 56.2 How Wolves Change Rivers
• Media Clip 57.1 Tracking Dead Zones from Space
• Media Clip 58.1 New Species Found in the Twenty-First Century
• Media Clip B1 Interpreting Frequency Distributions

Tree of Life

• Interactive Tree of Life