A Unity and Diversity

A1.2 Nucleic acids

A2.2 Cell structure

A3.1 Diversity of organisms

A4.1 Evolution and speciation

A4.2 Conservation of biodiversity

B Form and Function

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

B4.1 Adaptation to environment

B4.2 Ecological niches

C Interaction and Interdependence

C1.1 Enzymes and metabolism

C1.2 Cell respiration

C1.3 Photosynthesis

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

D Continuity and Change

D1.1 DNA replication

D1.2 Protein synthesis

D1.3 Mutation and gene editing

D2.1 Cell and nuclear division

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

IB Biology SL Question Bank

Browse IB Biology SL practice questions by topic across the four syllabus themes, within the SL scope. Check available mark-scheme points as you revise.

Exam analysis

SL · 2010–2025

Past-paper evidence across IB Biology clusters around structure-function relationships, molecular information, regulated interactions and evolutionary change. The course pattern is strongest when students connect mechanisms across levels of organisation rather than learning each topic as isolated facts.

Papers analysed141in the analysed sample

Latest appearanceNovember 2025

Tagged question parts2431

Paper types5

Most tested syllabus areas

B Form and Function141 papers
C Interaction and Interdependence139 papers
D Continuity and Change139 papers
A Unity and Diversity131 papers

141 papers analysed · Tagging incomplete

Unity and Diversity

A1.1 WaterA1.2 Nucleic acidsA2.2 Cell structureA3.1 Diversity of organismsA4.1 Evolution and speciationA4.2 Conservation of biodiversity

Form and Function

B1.1 Carbohydrates and lipidsB1.2 ProteinsB2.1 Membranes and membrane transportB2.2 Organelles and compartmentalizationB2.3 Cell specializationB3.1 Gas exchangeB3.2 TransportB4.1 Adaptation to environmentB4.2 Ecological niches

Interaction and Interdependence

C1.1 Enzymes and metabolismC1.2 Cell respirationC1.3 PhotosynthesisC2.2 Neural signallingC3.1 Integration of body systemsC3.2 Defence against diseaseC4.1 Populations and communitiesC4.2 Transfers of energy and matter

Continuity and Change

D1.1 DNA replicationD1.2 Protein synthesisD1.3 Mutation and gene editingD2.1 Cell and nuclear divisionD2.3 Water potentialD3.1 ReproductionD3.2 InheritanceD3.3 HomeostasisD4.1 Natural selectionD4.2 Stability and changeD4.3 Climate change

Frequently Asked Questions

Which syllabus scope does the IB Biology SL question bank use?

The topic directory follows the Biology syllabus for first assessment 2025. Choose an SL topic or syllabus statement; HL-only areas are outside this route.

How can I find IB Biology SL practice questions by topic?

Choose a topic from the four-theme directory or the syllabus sidebar. Narrow the scope to the knowledge point you want to revise before opening its questions.

What answer support is available?

Review the answer and mark guidance available for the question you open. Check terminology, calculations and data interpretation against the available scoring points; the support varies between questions.

How is the Question Bank different from Practice and the course guide?

The Question Bank helps you browse questions for a chosen syllabus scope. Practice lets you configure a practice session. The IB Biology SL course guide explains the syllabus, assessment and study methods.