IB Biology Study Notes

Free, topic-by-topic revision notes for the current IB Biology syllabus. Each page explains the key concepts, defines the terms you need, and links straight to practice questions.

A1.1

Water

Theme A: Unity and Diversity A1.2

Nucleic acids

Theme A: Unity and Diversity A2.1

Origins of cells

Theme A: Unity and Diversity A2.2

Cell structure

Theme A: Unity and Diversity A2.3

Viruses

Theme A: Unity and Diversity A3.1

Diversity of organisms

Theme A: Unity and Diversity A3.2

Classification and cladistics

Theme A: Unity and Diversity A4.1

Evolution and speciation

Theme A: Unity and Diversity A4.2

Conservation of biodiversity

Theme A: Unity and Diversity B1.1

Carbohydrates and lipids

Theme B: Form and Function B1.2

Proteins

Theme B: Form and Function B2.1

Membranes and membrane transport

Theme B: Form and Function B2.2

Organelles and compartmentalization

Theme B: Form and Function B2.3

Cell specialization

Theme B: Form and Function B3.1

Gas exchange

Theme B: Form and Function B3.2

Transport

Theme B: Form and Function B3.3

Muscle and motility

Theme B: Form and Function B4.1

Adaptation to environment

Theme B: Form and Function B4.2

Ecological niches

Theme B: Form and Function C1.1

Enzymes and metabolism

Theme C: Interaction and Interdependence C1.2

Cell respiration

Theme C: Interaction and Interdependence C1.3

Photosynthesis

Theme C: Interaction and Interdependence C2.1

Chemical signalling

Theme C: Interaction and Interdependence C2.2

Neural signalling

Theme C: Interaction and Interdependence C3.1

Integration of body systems

Theme C: Interaction and Interdependence C3.2

Defence against infectious disease

Theme C: Interaction and Interdependence C4.1

Populations and communities

Theme C: Interaction and Interdependence C4.2

Transfers of energy and matter

Theme C: Interaction and Interdependence D1.1

DNA replication

Theme D: Continuity and Change D1.2

Protein synthesis

Theme D: Continuity and Change D1.3

Mutation and gene editing

Theme D: Continuity and Change D2.1

Cell and nuclear division

Theme D: Continuity and Change D2.2

Gene expression

Theme D: Continuity and Change D2.3

Water potential

Theme D: Continuity and Change D3.1

Reproduction

Theme D: Continuity and Change D3.2

Inheritance

Theme D: Continuity and Change D3.3

Homeostasis

Theme D: Continuity and Change D4.1

Natural selection

Theme D: Continuity and Change D4.2

Stability and change

Theme D: Continuity and Change D4.3

Climate change

Theme D: Continuity and Change