IB Biology IA examples, experiments and research questions
The Biology IA is a 6–12 page individual investigation worth 20% of your final grade. Criterion helps you scope a feasible experiment — and grades your draft against the official IB Biology IA markscheme.
Example research questions
- Catalase + caffeine: How does caffeine concentration affect the rate of catalase activity in potato extract, measured by oxygen production?
- Yeast fermentation + pH: How does pH affect the rate of fermentation in Saccharomyces cerevisiae, measured by CO₂ produced per minute?
- Photosynthesis + wavelength: How does light wavelength affect the rate of photosynthesis in Elodea, measured by oxygen bubble count?
- Germination + soil moisture: How does soil moisture affect the percentage germination of cress seeds over 7 days?
Criteria scored
- Personal Engagement: Genuine curiosity and personal input into the design.
- Exploration: Focused RQ, justified methodology, controlled variables, awareness of safety/ethics.
- Analysis: Sufficient data, appropriate processing, uncertainty, and clear graphical presentation.
- Evaluation: Conclusion linked to RQ and theory; honest evaluation of limitations and improvements.
- Communication: Clear, concise, well-structured report using correct biological terminology.
Frequently asked questions
- How long is the IB Biology IA?
- The Biology IA is 6–12 pages (recommended) and worth 20% of your final Biology grade.
- How is the Biology IA marked?
- Marked out of 24 across five criteria: Personal Engagement (2), Exploration (6), Analysis (6), Evaluation (6), Communication (4).
- Can Criterion help me design a Biology IA experiment?
- Yes. Brainstorming mode helps you turn a curiosity into an investigable RQ with a feasible methodology.
- Will Criterion write my Biology IA?
- No. Criterion never writes or paraphrases.