Criterion Explainer

Understand exactly what each IB assessment criterion is looking for — plain-language breakdowns, mark-band descriptions, and annotated examples.

Subject

Criteria

24 marks total

Science IA · Criteria A–E · 24 marks

Biology IAs favour wet-lab work and living organisms. Your background must explain the biochemical or physiological mechanism that links your IV to your DV. Name your organism precisely (e.g. Solanum tuberosum), use ≥5 IV levels, and propagate uncertainty through every calculated rate or mean.

Personal Engagement

Max 2 marks

In plain language

Show the examiner this is genuinely YOUR investigation. Not just 'I find biology interesting' — but that you made real decisions, thought about them, and cared about what you found.

What examiners look for

A specific, personal reason for this exact topic — not a generic interest statement
Evidence of independent decisions you made (method, variable range, organism choice)
Reflection on what you discovered or what surprised you
Your voice throughout — not only in the introduction

Mark bands

0 mark

Purely descriptive. No personal connection to the investigation.

1 marks

Some personal input (a reason for the topic), but independent thinking and reflection are not clearly shown.

2 marks

Clear personal engagement: specific reason, evidence of independent decisions, and authentic reflection on findings or process.

Most common mistake

'I chose this topic because I find biology interesting.' This is generic, not personal. Describe a specific observation, experience, or question that led you to this exact investigation.

iBacalao helps you understand and revise your work. It should not replace your teacher's guidance or write your IA for you.