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CK-12 Biology Concepts
CK-12 Understanding Biodiversity
Human Biology - Breathing
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Human Biology - Circulation
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Teacher Edition
Human Biology - Digestion and Nutrition
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Teacher Edition
Human Biology - Ecology
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Teacher Edition
Human Biology - Genetics
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Human Biology - Lives of Cells
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Teacher Edition
Human Biology - Nervous System
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Human Biology - Reproduction
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Human Biology - Sexuality
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Human Biology - Your Changing Body
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Teacher Edition
Introduction to Biology
Scientific Investigation
Science Experiments
Scientific Theories
Characteristics of Life
Principles of Biology
Interdependence of Living Things
Organization of Living Things
Evolution of Life
Cell Biology
Chemistry of Life
Significance of Carbon
Carbohydrates
Proteins
Lipids
Nucleic Acids
Biochemical Reactions
Energy and Biochemical Reactions
Types of Biochemical Reactions
Enzymes
Enzyme Function
Water and Life
Acids and Bases in Biology
Common Parts of the Cell
Cytoplasm and Cytoskeletons
Organization of Cells
Prokaryotic and Eukaryotic Cells
Viruses
Plant Cell Structures
Phospholipid Bilayers
Membrane Proteins
Cell Nucleus
Ribosomes and Mitochondria
Other Cell Organelles
Diffusion
Osmosis
Facilitated Diffusion
Active Transport
Sodium-Potassium Pump
Exocytosis and Endocytosis
Autotrophs and Heterotrophs
Glucose and ATP
Chloroplasts
Light Reactions of Photosynthesis
Calvin Cycle
Chemosynthesis
Cellular Respiration
Glycolysis
Krebs Cycle
Electron Transport
Anaerobic vs Aerobic Respiration
Fermentation
Anaerobic and Aerobic Respiration
Cell Cycle, Mitosis, and Meiosis
Cell Division
Cell Cycle
Chromosomes
Mitosis and Cytokinesis
Asexual vs. Sexual Reproduction
Meiosis
Gametogenesis
Genetic Variation
Reproductive Life Cycles
Molecular Biology and Genetics
Gregor Mendel and Genetics
Mendel's Pea Plants
Mendel's First Set of Experiments
Mendel's Second Set of Experiments
Mendel's Laws and Genetics
Probability and Inheritance
Punnett Squares
Non-Mendelian Inheritance
Central Dogma of Molecular Biology
DNA, the Genetic Material
DNA Structure and Replication
RNA
Transcription of DNA to RNA
Genetic Code
Translation of RNA to Protein
Mutation Types
Mutation Causes
Mutation Effects
Gene Expression
Prokaryotic Gene Regulation
Eukaryotic Gene Regulation
Human Genome
Human Chromosomes and Genes
Genetic Linkage
Mendelian Inheritance in Humans
Genetic Disorders
Biotechnology
Biotechnology Applications
Ethical, Legal, and Social Issues of Biotechnology
Evolution
History of Life
How Earth Formed
First Organic Molecules
First Cells
Evolution of Eukaryotes
Late Precambrian Period
Life During the Paleozoic
Mesozoic Era - The Age of Dinosaurs
Cenozoic Era - The Age of Mammals
Linnaean Classification
Phylogenetic Classification
Darwin's Voyage of the Beagle
Influences on Darwin
Theory of Evolution by Natural Selection
Evidence for Evolution
Fossils
Living Species
Biogeography
Population Genetics
Hardy-Weinberg Theorem
Forces of Evolution
Natural Selection
Origin of Species
Types of Evolution
Coevolution
Macroevolution
Animal Evolution
Ecology
Ecosystems
Flow of Energy
Food Chains and Food Webs
Trophic Levels
Biogeochemical Cycles
Water Cycle
Carbon Cycle
Nitrogen Cycle
Terrestrial Biomes
Climate Effects on Biomes
Aquatic Biomes
Freshwater and Wetlands Biomes
Aquatic Organisms
Predation
Competition
Symbiosis
Succession
Population Size, Density, and Distribution
Population Structure
Population Growth
Population Growth Patterns
Human Population
Demographic Transition
Recent and Future Population Growth
Biodiversity
Importance of Biodiversity
Human Actions and the Sixth Mass Extinction
Renewable and Nonrenewable Resources
Soil and Water Resources
Air Pollution
Global Climate Change
Prokaryotes, Viruses, Protists and Fungi
Prokaryote Evolution
Prokaryote Classification
Prokaryote Structure
Prokaryote Metabolism
Prokaryote Habitats
Prokaryote Reproduction
Bacteria and Humans
Virus Characteristics
Virus Structures
Virus Classification
Virus Replication
Discovery and Origin of Viruses
Viruses and Human Disease
HIV
Control of Viruses
Viruses in Research and Medicine
Protist Kingdom
Protist Evolution
Protist Characteristics
Protozoa
Algae
Molds
Fungi
Fungi Structure
How Fungi Eat
Fungi Reproduction
Fungi Evolution
Fungi Classification
Symbiotic Relationships of Fungi
Human Uses of Fungi
Protists and Human Disease
Fungi and Human Disease
Plants
Plant Classification
Plant Characteristics
Importance of Plants
Early Evolution of Plants
Evolution of Seed Plants
Nonvascular Plants
Vascular Plants
Seed Plants
Flowering Plants
Plant Biology
Plant Cells
Plant Tissues
Plant Growth
Roots
Stems
Leaves
Plant Life Cycle Overview
Photosynthesis
Plant Life Cycles
Life Cycle of Nonvascular Plants
Life Cycle of Seedless Vascular Plants
Gymnosperm Life Cycle
Angiosperm Life Cycle
Plant Adaptations
Plant Responses
Animals
Animal Characteristics
Animal Classification
Invertebrate Characteristics
Invertebrate Evolution
Invertebrate Classification
Invertebrates
Sponges
Cnidarians
Flatworms
Roundworms
Mollusks
Annelids
Arthropods
Insects
Echinoderms
Chordates
Invertebrate Chordates
Vertebrate Characteristics
Vertebrate Reproduction
Vertebrate Classification
Vertebrate Evolution
Fish Structure and Function
Fish Reproduction and Development
Fish Classification
Fish Evolution and Ecology
Amphibian Structure and Function
Amphibian Reproduction and Development
Amphibian Classification
Amphibian Evolution and Ecology
Reptile Structure and Function
Reptile Reproduction
Reptile Classification
Reptile Evolution
Reptile Ecology
Bird Structure and Function
Bird Reproduction
Bird Classification
Bird Evolution
Bird Ecology
Mammal Characteristics
Mammal Structure and Function
Mammal Endothermy
Mammal Living and Locomotion
Placental Mammals
Marsupials
Monotremes
Mammal Ancestors
Evolution of Early Mammals
Evolution of Modern Mammals
Mammal Classification
Evolution of Animal Behavior
Innate Behavior of Animals
Learned Behavior of Animals
Social Behavior of Animals
Cyclic Behavior of Animals
Reproductive Behavior of Animals
Human Biology
Carcinogens and Cancer
Air Pollution and Illness
Bioterrorism
Organization of the Human Body
Homeostasis
Human Skeletal System
Structure of Bones
Growth and Development of Bones
Skeletal System Problems and Diseases
Skeletal System Joints
Smooth, Skeletal, and Cardiac Muscles
Skeletal Muscles
Muscle Contraction
Skin
Nails and Hair
Nervous and Endocrine Systems
Nerve Cells
Nerve Impulses
Central Nervous System
Peripheral Nervous System
Senses
Drugs and the Nervous System
Nervous System Disorders
Glands
Hormones
Hormone Regulation
Endocrine System Disorders
Heart
Blood Vessels
Blood
Circulatory System
Circulatory System Diseases
Respiration
Respiratory System Organs
Respiratory System Regulation
Respiratory System Diseases
Processes of Breathing
Human Digestive System
Digestive System Organs
Digestion
Small Intestine
Large Intestine
Digestive System Diseases
Food and Nutrients
Balanced Eating
Excretion
Urinary System
Excretory System Diseases
Kidneys
Immune System and Disease
Barriers to Pathogens
Preventing Noninfectious Diseases
Inflammatory Response and Leukocytes
Lymphatic System
B and T Cell Response
Humoral Immune Response
Cell-Mediated Immune Response
Immunity
Allergies
Autoimmune Diseases
Immunodeficiency
HIV and AIDS
Reproduction and Human Development
Male Reproductive Structures
Male Reproductive Development
Human Sperm
Female Reproductive Structures
Female Reproductive Development
Human Egg Cells
Menstrual Cycle
Fertilization
Embryo Growth and Development
Fetus Growth and Development
Fetal Development and the Placenta
Pregnancy and Childbirth
Development from Birth to Adulthood
Adulthood and Aging
Sexually Transmitted Infections
Bacterial Sexually Transmitted Infections
Viral Sexually Transmitted Infections
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