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Biology organized around your syllabus
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Organized around eight AP Biology units — official College Board syllabus.
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Find the Biology concept you need without searching through a long list of unrelated articles.
Cell Biology
Cell structure, organelles and the cell cycle.
ExploreBiomolecules & Biochemistry
Proteins, enzymes, lipids and carbohydrates.
ExploreMolecular Biology
DNA, RNA, replication and gene expression.
ExploreGenetics & Heredity
Inheritance, genes and chromosomes.
ExplorePlant Biology
Plant structure, nutrition and growth.
ExploreHuman Physiology
How the body's systems work together.
ExploreReproduction & Development
From gametes to growth and life cycles.
ExploreEcology & Environment
Ecosystems, populations and the environment.
ExploreDiversity, Classification & Biodiversity
Taxonomy, kingdoms and the variety of life.
ExploreEvolution & Natural Selection
Origin of life, adaptation and speciation.
ExploreBiotechnology & Bioinformatics
Genetic engineering, tools and data.
ExploreHealth, Disease & Immunology
Pathogens, immunity and human health.
ExploreAnimal Biology
Animal structure, diversity and behaviour.
ExploreMicrobiology
Bacteria, viruses, fungi and microbes in life.
ExploreNeuroscience & Behaviour
Neurons, the nervous system and coordination.
ExploreBioenergetics
Photosynthesis, respiration and energy flow.
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