Crafting a clear and thoughtful conclusion for your IB Biology IA is crucial for achieving a high score. In this section, you should summarize your main findings, interpret the results using relevant biological concepts, and discuss any uncertainties in your investigation. Essentially, the conclusion condenses and communicates your experimental outcomes effectively to the examiner. This post will highlight important tips to consider when writing your Biology IA conclusion.
Begin your conclusion by briefly restating the aim of your experiment. This reminds the reader of the focus and purpose of your investigation. Keep it concise but specific, mentioning the independent and dependent variables. This sets the context for interpreting your findings and evaluating how effectively your investigation addressed its main objective. For a good example of this, click here.
Summarize the key trends or patterns observed in your graphs and explain how these relate to your research question. Describe whether the relationship was linear, exponential, or inverse, and link this trend to the theoretical expectations. Showing how your graphical data supports or challenges the expected biology principle strengthens your analytical depth and shows that you can critically analyze the results of your experiment. A good example can be seen here.
If your data is linear, mention the R² value from your graph and interpret what it indicates about the strength of the correlation between variables. A value close to 1 suggests a good linear fit and strong correlation between variables, while a lower value indicates a weak correlation. Explaining the R2 value shows how well your experimental data supports theoretical expectations. For example, if linear results are expected and you get a high R2 value, you can explain that your data is reliable. However, if there is a weak correlation due to a low R2 value, you can explain what may have caused it. A good explanation of the R2 value can be read here.
Use experimental values
Refer directly to numerical data or calculated results to make your conclusion evidence-based. For example, instead of general statements (e.g. The volume of CO2 produced increased with temperature), use specific values to demonstrate your findings (e.g. The volume of CO2 increased from 10.3 cm³ at 20 ºC to 50.7 cm³ at 60 ºC). This adds precision and specificity to your interpretation and demonstrates that your claims are supported by data rather than vague observations or assumptions. This also shows that you can critically evaluate which numerical values are important and should be highlighted against the rest. A good example can be found here.
Discuss the extent to which the research question was answered
Evaluate whether your investigation fully or only partially addressed the research question. Reflect on how well your data supports your conclusion and whether any limitations prevented complete resolutions to your investigations. If the research question was only partially answered, explain why and discuss what could have been done to result in a fully answered research question.
Describe and explain anomalies or deviations from expected results
Describe whether your results follow the expected trends or not. If your results differ from the expected trends, suggest reasonable explanations for these deviations, such as measurement inaccuracies, uncontrolled environmental conditions, variation in biological samples, or limitations in experimental equipment. Note that these issues may be briefly stated in the conclusion, but should be thoroughly explained later in the evaluation. A good discussion of a deviation from expected results can be found here.
Compare experimental and literature values
Compare your measured or calculated values with accepted theoretical or literature values to assess the accuracy of your results. Discuss how closely your results align (i.e. if the values are in a similar range) and provide explanations for any discrepancies. This comparison of experimental and literature values will help validate your findings and provide an accredited scientific benchmark for evaluating your experiment's results. A good example of this is present here.
Discuss the impact of uncertainties
Evaluate how measurement uncertainties affected your results. Determine whether they were relatively small or large compared to the measured values. For example, in a Biology IA investigating enzyme activity, a reaction rate of 12.5 μmol/min ± 0.1 μmol/min indicates high precision and consistent results, whereas 12.5 μmol/min ± 2.0 μmol/min suggests lower precision and greater uncertainty in the data. Analyzing the significance of uncertainties shows your understanding of the reliability of your experimental results. A good example of an uncertainty discussion can be seen in this exemplar.
We hope this post has helped you learn more about how to write an IB Biology IA conclusion. For more useful materials associated with the IB, check out the wide variety of IA, EE and TOK exemplars available at Clastify and other guides available on our blog.