AP Biology AP生物学
📌 Course at a glance
· 8 units · key topics drilled across the official outline
· Next exam: 2026-05-11 · 2026-05-11
📝 Full chapter-by-chapter lecture walkthroughs are being written. This page is the course outline — every unit and topic that will be covered, with key concepts you can already start to recognise. Use it as a study map; the chapter notes drop in over the coming weeks.
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Course outline
Unit 1 · Chemistry of Life 生命的化学基础
Exam weight: 8-11%
1.1 — Structure of Water and Hydrogen Bonding 水的结构与氢键
· Polarity of water molecules · Mechanism of hydrogen bond formation · Special properties of water (high specific heat, cohesion, solvent properties)
1.2 — Elements of Life 生命的元素
· Major elements in living organisms (C, H, O, N, P, S) · Biological functions of trace elements · Carbon skeleton and diversity of organic molecules
1.3 — Introduction to Biological Macromolecules 生物大分子简介
· Overview of four classes of biological macromolecules · Concept of monomers and polymers · Dehydration synthesis and hydrolysis reactions
1.4 — Properties of Biological Macromolecules 生物大分子的性质
· Classification and functions of carbohydrates · Types and properties of lipids · Levels of protein structure
1.5 — Structure and Function of Biological Macromolecules 生物大分子的结构与功能
· Four levels of protein structure · Principle of structure determines function · Effect of environmental factors on macromolecular structure (denaturation)
1.6 — Nucleic Acids 核酸
· Structural comparison of DNA and RNA · Composition of nucleotides · Base complementary pairing rules
Unit 2 · Cell Structure and Function 细胞结构与功能
Exam weight: 10-13%
2.1 — Cell Structure: Subcellular Components 细胞结构：亚细胞组分
· Comparison of prokaryotic and eukaryotic cells · Structure and function of major organelles · Components of the endomembrane system
2.2 — Cell Structure and Function 细胞结构与功能
· Coordinated functions among organelles · Adaptation of structure and function · Differences between plant and animal cells
2.3 — Cell Size 细胞大小
· Surface area to volume ratio · Limiting factors of cell size · Effect of cell shape on transport efficiency
2.4 — Plasma Membranes 细胞膜
· Fluid mosaic model · Structure of the phospholipid bilayer · Types and functions of membrane proteins
2.5 — Membrane Transport 膜运输
· Passive and active transport · Principles of free diffusion · Concentration gradient and direction of transport
2.6 — Facilitated Diffusion 协助扩散
· Channel proteins and carrier proteins · Characteristics of facilitated diffusion · Ion channels and aquaporins
2.7 — Tonicity and Osmoregulation 渗透压与渗透调节
· Isotonic, hypertonic, and hypotonic solutions · Principles of osmosis · Response of plant and animal cells in different osmotic environments
2.8 — Mechanisms of Transport 运输机制
· Relationship between active transport and ATP · Mechanism of the sodium-potassium pump · Endocytosis and exocytosis
2.9 — Cell Compartmentalization 细胞区隔化
· Advantages of compartmentalization · Role of membrane systems in cell function · Microenvironments of different organelles
2.10 — Origins of Cell Compartmentalization 细胞区隔化的起源
· Endosymbiotic theory · Evidence for the origin of mitochondria and chloroplasts · Evolution of eukaryotic cells
Unit 3 · Cellular Energetics 细胞能量学
Exam weight: 12-16%
3.1 — Enzyme Structure 酶的结构
· Protein nature of enzymes · Relationship between active site and substrate · Enzyme specificity (lock-and-key model and induced fit model)
3.2 — Enzyme Catalysis 酶催化
· Mechanism by which enzymes lower activation energy · Factors affecting enzyme reaction rate · Relationship between substrate concentration and reaction rate
3.3 — Environmental Impacts on Enzyme Function 环境对酶功能的影响
· Effects of temperature and pH on enzyme activity · Enzyme denaturation and optimal conditions · Competitive and noncompetitive inhibition
3.4 — Cellular Energy 细胞能量
· Structure and function of ATP · Interconversion of ATP and ADP · Coupling of free energy and metabolic reactions
3.5 — Photosynthesis 光合作用
· Light reactions and Calvin cycle · Photosynthetic pigments and light absorption · Overall equation and location of photosynthesis
3.6 — Cellular Respiration 细胞呼吸
· Glycolysis, pyruvate oxidation, citric acid cycle · Oxidative phosphorylation and electron transport chain · Comparison of aerobic and anaerobic respiration
3.7 — Fitness 适合度
· Metabolic efficiency and biological fitness · Energy allocation strategies · Evolutionary significance of metabolic pathways
Unit 4 · Cell Communication and Cell Cycle 细胞通讯与细胞周期
Exam weight: 10-15%
4.1 — Cell Communication 细胞通讯
· Types of cell communication (autocrine, paracrine, endocrine) · Types of signal molecules · Direct contact communication
4.2 — Introduction to Signal Transduction 信号转导简介
· Basic steps of signal transduction · Receptor-ligand binding · Components of cell signaling pathways
4.3 — Signal Transduction 信号转导
· Signal amplification mechanisms · Second messengers (e.g., cAMP, Ca2+) · Phosphorylation cascades
4.4 — Changes in Signal Transduction Pathways 信号转导通路的变化
· Consequences of signaling pathway mutations · Cancer and abnormal signal transduction · Drug intervention in signaling pathways
4.5 — Feedback 反馈调节
· Positive and negative feedback mechanisms · Feedback regulation to maintain homeostasis · Examples of feedback in biological systems
4.6 — Cell Cycle 细胞周期
· Phases of the cell cycle (G1, S, G2, M phase) · Process of mitosis · Cytokinesis
4.7 — Regulation of Cell Cycle 细胞周期的调控
· Cell cycle checkpoints · Cyclins and cyclin-dependent kinases · Loss of cell cycle control and cancer
Unit 5 · Heredity 遗传学
Exam weight: 8-11%
5.1 — Meiosis 减数分裂
· Process of meiosis I and meiosis II · Separation of homologous chromosomes · Comparison of meiosis and mitosis
5.2 — Meiosis and Genetic Diversity 减数分裂与遗传多样性
· Crossing over and genetic recombination · Law of Independent Assortment · Random fertilization increases genetic variation
5.3 — Mendelian Genetics 孟德尔遗传学
· Law of Segregation · Law of Independent Assortment · Genetic diagrams and predicting phenotypic ratios
5.4 — Non-Mendelian Genetics 非孟德尔遗传
· Incomplete dominance and codominance · Polygenic inheritance · Linkage and crossing over · Epigenetics
5.5 — Environmental Effects on Phenotype 环境对表现型的影响
· Relationship between genotype and phenotype · Environmental effects on gene expression · Phenotypic plasticity
5.6 — Chromosomal Inheritance 染色体遗传
· Sex-linked inheritance · Chromosomal number abnormalities (aneuploidy) · Chromosomal structural variations
Unit 6 · Gene Expression and Regulation 基因表达与调控
Exam weight: 12-16%
6.1 — DNA and RNA Structure DNA和RNA的结构
· DNA double helix structure · Types of RNA (mRNA, tRNA, rRNA) · Chemical structure of nucleotides
6.2 — Replication DNA复制
· Semiconservative replication mechanism · Role of DNA polymerase · Synthesis of leading and lagging strands
6.3 — Transcription and RNA Processing 转录与RNA加工
· Basic process of transcription · RNA polymerase and promoters · Eukaryotic RNA processing (5' capping, 3' poly-A tail, splicing)
6.4 — Translation 翻译
· Codons and anticodons · Function of ribosomes · Initiation, elongation, and termination of translation
6.5 — Regulation of Gene Expression 基因表达的调控
· Operon model in prokaryotes · Levels of gene regulation in eukaryotes · Transcription factors and enhancers
6.6 — Gene Expression and Cell Specialization 基因表达与细胞特化
· Cell differentiation and differential gene expression · Properties of stem cells · Gene regulation during development
6.7 — Mutations 突变
· Types of point mutations (missense, nonsense, silent) · Frameshift mutations · Effects of mutations on protein structure and function
Unit 7 · Natural Selection 自然选择
Exam weight: 13-20%
7.1 — Introduction to Natural Selection 自然选择简介
· Core ideas of Darwin's theory of natural selection · Concept of adaptation · Prerequisites for natural selection
7.2 — Natural Selection 自然选择
· Directional, stabilizing, and disruptive selection · Fitness and reproductive success · Natural selection acts on phenotypes
7.3 — Artificial Selection 人工选择
· Principles and examples of artificial selection · Comparison of artificial and natural selection · Applications of selective breeding
7.4 — Population Genetics 群体遗传学
· Concept of the gene pool · Allele frequencies · Factors affecting allele frequencies
7.5 — Hardy-Weinberg Equilibrium 哈迪-温伯格平衡
· Conditions of Hardy-Weinberg equilibrium · Application of p squared + 2pq + q squared = 1 · Causes of deviation from Hardy-Weinberg equilibrium
7.6 — Evidence of Evolution 进化的证据
· Fossil record · Comparative anatomy (homologous and analogous structures) · Molecular biological evidence
7.7 — Common Ancestry 共同祖先
· Evidence for common ancestry of life · Universality of the genetic code · Comparison of conserved gene sequences
7.8 — Continuing Evolution 持续进化
· Evolution of antibiotic resistance · Effects of modern human activities on evolution · Ongoing and dynamic nature of evolution
7.9 — Phylogeny 系统发育
· Construction and interpretation of phylogenetic trees · Basic methods of cladistics · Molecular clocks and rates of evolution
7.10 — Speciation 物种形成
· Geographic isolation and allopatric speciation · Sympatric speciation · Reproductive isolation mechanisms
7.11 — Extinction 灭绝
· Causes of extinction · Mass extinction events · Effects of extinction on biodiversity
7.12 — Variations in Populations 群体中的变异
· Sources of genetic variation · Genetic drift and bottleneck effect · Gene flow and mutation
7.13 — Origin of Life on Earth 地球上生命的起源
· Chemical evolution hypothesis · RNA world hypothesis · Early Earth environment and formation of organic molecules
Unit 8 · Ecology 生态学
Exam weight: 10-15%
8.1 — Responses to the Environment 对环境的响应
· Fundamentals of behavioral ecology · Innate and learned behaviors · Taxis, phototaxis, and biological rhythms
8.2 — Energy Flow Through Ecosystems 生态系统中的能量流动
· Food chains and food webs · Trophic levels and energy transfer efficiency · Ecological pyramids
8.3 — Population Ecology 种群生态学
· Population growth models (exponential and logistic growth) · Carrying capacity (K) · Population density and distribution
8.4 — Effect of Density of Populations 种群密度的影响
· Density-dependent and density-independent factors · Intraspecific competition · Density-dependent disease transmission
8.5 — Community Ecology 群落生态学
· Interspecific relationships (competition, predation, mutualism, parasitism) · Concept of ecological niche · Community succession
8.6 — Biodiversity 生物多样性
· Species diversity, genetic diversity, and ecosystem diversity · Importance of biodiversity · Concept of keystone species
8.7 — Disruptions to Ecosystems 生态系统的干扰
· Impact of human activities on ecosystems · Harm from invasive species · Climate change and ecosystem responses