IB Bio Paper 1 – Top Revision Tips

Tony has been teaching Science to middle school and high school students for over two decades over a range of curricula. We’ve invited him to share his top revision tips for IB Biology Paper 1.

Article reviewed and updated by Tony, 23rd  June 2025.

The exam season is on the horizon, but your IB Biology Paper 1 doesn’t have to be a source of that stress! In this article Tony will break down the paper, and help you understand the groups of questions and the tactics to increase your chance of success. Whether you are taking HL or SL IB Biology these tips will help you approach your final IB Paper 1 exam with confidence.

What to expect from IB Biology Paper 1

The new IB Biology syllabus had its first assessment in May 2025 and included changes to Biology Paper 1, with some key differences for SL and HL students.

• Duration: 1 hour 30 minutes total for SL; and 2 hours for HL.
• Paper 1A: 30 multiple-choice questions for SL or 40 multiple-choice questions for  HL
• Paper 1B: Four data-based questions related to experimental work and the syllabus for both HL and SL students with a few more total marks in the HL version.
• Paper 1 covers all four syllabus themes: Unity & Diversity, Form & Function, Interaction & Interdependence, Continuity & Change.
• In Paper 1 there is no longer negative marking so always try to answer everything!
• A calculator is allowed for both sections.

The questions are short and sweet and are designed to be only one or two-stage problems.  The questions address objectives 1, 2 and 3 (see the objectives below).

1. Demonstrate an understanding of Scientific:
   1. facts and concepts
   2. methods and techniques
   3. terminology
   4. methods of presenting scientific information.
2. Apply and use Scientific:
   1. facts and concepts
   2. methods and techniques
   3. terminology to communicate effectively
   4. appropriate methods to present scientific information.

While all our IB Biology experts agree that practise, practise, practise is the most important thing you can do, Tony has some very specific tips that should help you nail this paper.

During your IB Biology Revision for Paper 1, you can use his top 6 tips to get yourself up to speed and on track to do your best. So, here they are;

Tip 1 – Learn question “families”

The multiple-choice questions will hit recurring concepts— so it’s important to recognise patterns like “enzyme action”, “water potential”, “cell structure”.

Use practise papers or question banks to help you “read ahead” and anticipate twists in phrasing.

Tip 2 – Target strengths first

Read through all questions at the start, mark those you can confidently answer, and tackle those first.

Tony says,

Start with what you know—get these marks early on and then you have a bit more time to consider the ones you need more time on. Remember you don’t have to answer the questions in order.

This prevents getting stuck early and frees up time for more challenging data questions. 

Tip 3 – Use elimination effectively

For each multiple-choice question, identify and rule out obviously wrong answers quickly.

Tony emphasises the importance of re-reading the wording very carefully— as paper writers often drop subtle clues in phrasing.

When teaching IB Biology I have an old favourite MCQ where language is used to subtly check understanding. It is a past paper question where students are asked about properties of water that depend on “intermolecular” or intramolecular” bonds….Perhaps more of a check on language skills than your Biology skills!

Tip 4 – Be ready for diagram interpretation

Some MCQs will feature images like cell ultrastructure or membrane diagrams, similar to your drawing practice.

So Tony says it’s important to know how to label, identify, and explain structures like mitochondria, ER, chloroplasts. This means seeing as many electron micrographs as possible, so that you know the differences between “Smooth” and “Rough” endoplasmic reticulum and can tell by looking.

If a cell has enough Golgi apparatus to suggest it will excrete lots of hormones or is crammed with mitochondria, suggesting a high energy production and consumption like muscle tissues, these are significant clues in identifying which type of cell it might be.

Tip 5 – Master data interpretation

In Paper 1B, Tony says to expect tables, graphs, or experimental setups.

I always recommend looking at as many past papers with data analysis questions, so that you get familiar with the format and the breadth of ways in which data can be represented in IB Biology graphs.

Identify variables, control conditions, and trends in the data and pay close attention to the units used and the scales on the graph axes.

Finally, get comfortable with basic descriptive statistics (mean, standard deviation) and explain anomalies or uncertainties.

Tip 6 – Calculator confidence

Although simple arithmetic is needed, Tony recommends using a calculator to avoid errors. However, practise estimating and checking results:

Don’t rely solely on a calculation where you might have mistyped a key on the calculator. Always try to have some idea of the scale of the answer before using the calculator. Does the answer you get make sense?

Before Exam Day

1. Drill with specimen papers (Paper 1A/1B SL & HL)
2. Time yourself to make sure you are on track. Tony says, “I tell my students to aim roughly for 1.5 minutes per mark available. Sometimes you might go faster on multiple choice questions and gain some time for the longer answers sections.”
3. Review diagrams, ensure you’re fluent with labeling and interpreting structures
4. Practice data questions: describe trends, draw conclusions, evaluate reliability.

If you would like more articles on the other IB Biology papers, more tips on IB Biology Paper 2 and Paper 3 are here.

To book a lesson with one of our IB Biology Examiners check out our IB Biology page HERE.

In case you want to review the course outline on the IBO site, click HERE.