GCSE
IGCSE
IB
A-Level
Revise
How it works
Pricing
For parents
For schools
Log in
Start 7-day free trial
IB
›
IB Biology HL
IB Biology HL Revision notes
Clear notes for every subtopic, with key terms and exam tips.
Unity and diversity
9 subtopics
A1.1 Water
A1.2 Nucleic acids
A2.1 Origins of cells
A2.2 Cell structure
A2.3 Viruses
A3.1 Diversity of organisms
A3.2 Classification and cladistics
A4.1 Evolution and speciation
A4.2 Conservation of biodiversity
Form and function
10 subtopics
B1.1 Carbohydrates and lipids
B1.2 Proteins
B2.1 Membranes and membrane transport
B2.2 Organelles and compartmentalization
B2.3 Cell specialization
B3.1 Gas exchange
B3.2 Transport
B3.3 Muscle and motility
B4.1 Adaptation to environment
B4.2 Ecological niches
Interaction and interdependence
9 subtopics
C1.1 Enzymes and metabolism
C1.2 Cell respiration
C1.3 Photosynthesis
C2.1 Chemical signalling
C2.2 Neural signalling
C3.1 Integration of body systems
C3.2 Defence against disease
C4.1 Populations and communities
C4.2 Transfers of energy and matter
Continuity and change
12 subtopics
D1.1 DNA replication
D1.2 Protein synthesis
D1.3 Mutation and gene editing
D2.1 Cell and nuclear division
D2.2 Gene expression
D2.3 Water potential
D3.1 Reproduction
D3.2 Inheritance
D3.3 Homeostasis
D4.1 Natural selection
D4.2 Stability and change
D4.3 Climate change