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Biology IA Checklist

How To Write a Perfect Biology IA

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How to Write Your IB Biology Internal Assessment

By TutorsPlus

Performing well on the IB Internal Assessment requires a lot of work. This includes careful planning, research, experimentation, analysis, and writing. You should not take this assignment lightly since it accounts for 20% of your final grade. In this guide, we will explain in great detail how to write Biology IA to get a top score, so you can get the help you need every step along the way.

Our IB Biology Internal Assessment guide will cover both the necessary steps to take to conduct a successful investigation and the Biology IA structure.

What is the Biology Internal Assessment?

The IB Biology IA is a self-directed investigation into a Biology topic of your choice.

Your task is to design and conduct an experiment, analyse its results, and write a report about it. Typically, it takes around 10 hours of class time to work on the IA, but you will likely need to put in additional time outside of class. The final paper should be no longer than 3000 words.

A solid, well-designed IA can bring you a maximum of 24 points. To award these points, examiners take into account 4 marking criteria – learn more about them from this post .

The following guide on how to write Biology IA will show you how to meet these criteria and maximise your score. And remember, if you get stuck, our IB Biology tutors, teachers, and examiners are here to help.

The Five Steps to Writing IB Biology Internal Assessment

As we have already said, the Internal Assessment is one of the pillars of your end-of-the-course examination. Without completing your investigation, you cannot count on a good mark.

This means that you must treat your IB Biology IA as if you were a scientist for real, i.e. carefully plan what you’d like to do and which results you expect to obtain, carry out your experiment, and draw a conclusion. Here are these steps in more detail.

Choosing a Research Question

The first step is to choose a focused research question on a biological topic that interests you. The question should be specific enough to investigate through an experiment in the time available.

The best IB Biology Internal Assessments specify a clear reason why you chose such a topic. For example, you may investigate a biological phenomenon or issue that is relevant to the region where you live. Or it might be a topic that has fascinated you since childhood. Whatever your reasoning is, it must be clear from your work.

Still, it is not enough to choose a research question based solely on your interests. It should also be:

• Doable, i.e. you must be able to answer it taking into account time and resource limitations, as well as the level of complexity of an experiment;
• Measurable. In other words, your investigation should involve variables, which you can measure and analyse. It is also possible to work with statistical data.
• Unique. Your Biology IA doesn’t require you to do groundbreaking research. Nevertheless, you need to come up with an original question and contribute new insights to the chosen area of study.

Now sure which questions to use? Allow us to help you. We offer fresh 30+ IB Biology IA ideas . However, it is always best to use your own creative ideas, as examiners expect to see originality and thinking in your work.

Planning the Experiment

Once you have a research question, plan out how you are going to investigate it thoroughly. It is vital to consider every part of your work, from the variables you will measure, to the materials and methods you will use, and, of course, the data you aim to collect. 

However, before you begin to investigate, your teacher must approve your plan. Do not skip this step, as it could result in wasted time and effort if your teacher doesn’t agree with your IA proposal.

Conducting the Experiment

You need to carry out your experiment safely and systematically. Every observation and piece of data you obtain should be carefully recorded. It is important to repeat your experiment a few times to verify results as well as possibly find any errors and omissions in your methodology.

Analysing and Concluding

Examine your data to identify patterns and relationships. This data will help you draw conclusions to answer your original research question. For the best marks, you ought to discuss sources of error and suggest improvements for further investigation.

How to Write Biology IA: Structure and Points to Cover

When writing the IB Biology Internal Assessment, you need to follow a certain structure. A well-organised report will help ensure that you meet every marking criterion as well as demonstrate your thinking skills.

Here are our extensive guidelines for each section of your paper.

The Title and Contents Page

The Title Page sets the tone for the entire IB Biology Internal Assessment report. Your goal is to craft a descriptive title that reflects the purpose of the study. For example, “An Investigation into the Effect of X on Y.”

The title must be accompanied by a focused research question involving the key variables, units, time, and location, if applicable.

Below is an example of a title and a research question:

Title: The Influence of Light Intensity on the Rate of Photosynthesis in Elodea Plants.

Research Question: Does the intensity of light affect the rate of photosynthesis in Elodea (Elodea nuttallii), and if so, is there an optimal light intensity for maximizing photosynthetic activity?

Please note that if your experiment involves a living organism, you must identify it by both a common name and scientific name (genus and species).

When it comes to the Contents Page, it outlines the Biology IA structure and lists all sections and page numbers. This page is important to let examiners easily navigate the document.

Taking time with these initial pages will show your ability to be organised and thoughtful. The title and contents provide the first impression to evaluators.

Introduction

We suggest that you start your report with a brief overview of the topic and focus on its importance. For example, if your research involves a living organism or a compound, say where one might encounter it in everyday life, how we use it in food production or industrial processes, and explain the role it plays in an ecosystem.

Then, proceed from general to personal. What made you choose this topic and this research subject? Do they have a significance specifically for you or a global importance? Tell briefly about it at the beginning of your report.

Along with this, you should specify the method of investigation and why you used it. For instance, if you’re studying the effect of temperature on enzyme activity, you might want to use a sugar solution or specific chemical substrate to measure the enzyme’s effectiveness at different temperatures.

Overall, the introduction should be 0.5-1.0 pages long.

The next element of the appropriate IB Biology IA structure is background information. It helps understand the context of your research question and experiment.

For example, if you’re investigating a molecule, you need to describe its fundamental structure, i.e. identify its building blocks and how they are arranged. In case your subject is a consumable compound (such as capsaicin in chilli peppers or vitamin C), it is vital to discuss its effects on the body. You can explain their benefits and the potential harm associated with deficiencies or excessive consumption.

If your focus is a living organism, you need to pinpoint its key features and specify their impact on your experiment.

Often, IB Biology Internal Assessments involve reagents that react with a selected molecule or a compound. If you, too, have such reagents, explain their chemical structure and reactivity that make them suitable for your experiment. You shouldn’t forget to include relevant chemical equations.

It is not uncommon for Biology IAs to rely on secondary data instead of experiments. If you go this route, you must justify your choice of the specific database. Along with this, you should provide the data collection method and explain why this database is relevant to your research question.

If applicable, you can include diagrams, graphs, and other visual information. Don’t forget to cite the source you’re using and provide figure captions.

After you provide the scientific justification of your experiment, proceed to state your actual hypothesis. This should be an if-then statement outlining your testable prediction about the anticipated results.

Next, provide 2-3 sentences explaining your rationale. Link it logically to scientific principles and cite any research that informed your hypothesis. Your conclusion will either support your hypothesis or reject it.

Below is an example of a hypothesis:

“Exposure to different light intensities will affect the rate of photosynthesis in Elodea plants. I predict that as light intensity increases, the rate of photosynthesis will also increase due to the enhanced availability of light energy for the photosynthetic process. However, beyond this optimal level, I expect the rate of photosynthesis to plateau or even decrease due to factors like photoinhibition. This hypothesis is supported by the established principle that photosynthesis relies on light energy, and exceeding optimal light levels can damage photosynthetic machinery.”

Typically, biological investigations will involve three sets of variables: Independent, Dependent, and Controlled Variables:

• The independent variable is what you intentionally manipulate. You need to be highly specific about the increments tested.
• The dependent variable is what changes in response to manipulations. They are what you will be measuring.
• Controlled variables are held constant to isolate effects.

In your Internal Assessment, you need to list at least 5 control variables and do 15 repeats.

We suggest that you make a table with three columns introducing your variables. It must also feature units and, if applicable, ranges (for example, gas concentrations). Don’t forget to explain the instruments or methods you used to measure variables.

Your IA report must clearly show all the apparatus and equipment you used in your experiment.

To do so, you can draw and fully label a visual diagram of your experimental setup, especially detailing how the independent variable was implemented. For example, if testing temperature, show the water bath or incubator set at different temperatures.

Alternatively, you may take a photo of your actual lab setup and annotate it.

Either way, you must specify all the apparatus and instruments, as well as solutions and chemicals (with their concentrations) that your experiment requires. Whenever possible, discuss the uncertainties for your instruments (weighing balances, pipettes, etc.).

You can start this section with a Preliminary Experiment with the purpose of providing critical insights to guide the main investigation. You should explain how it shaped your methodology, analysis approach, and decision-making.

If you didn’t conduct a preliminary experiment, you need to research the independent variables and the method for measuring the dependent variable. This analysis will mimic the function of a preliminary experiment in informing the main investigation’s design.

The next important step is to write the experimental procedure in clear numbered steps. It is better to use the imperative mood to make it look like an instruction (“Heat the solution to 20 degrees Celsius …” instead of “I heated the solution…”). Make sure to include enough detail so that someone else would be able to repeat the process.

You need to include at least 5 increments of your independent variable (e.g. 5 temperatures) and a minimum of 5 trials/replicates per increment. Please keep in mind that your procedure should collect both quantitative data (numbers) and qualitative data (observational descriptions).

At the end of this section, it is important to discuss the risks involved in your experiment (such as safety, ethical, and environmental).

This section of your IB Biology Internal Assessment should include at least 3 data tables:

• Raw Data Table, which features only unprocessed numbers;
• Control Variables Table, which presents values of controlled variables, for instance, initial temperatures;
• Qualitative Data Table including observational descriptive details (for example, colour or temperature changes).

You need to give all these tables clear, descriptive titles. It is also essential to label all your columns with headings and units of measurement. You should make sure that your numbers are uniform, i.e. have the same decimal places. You are at risk of losing marks if you miss even a single unit.

We don’t recommend that you start your table on one page and continue on another. However, if you have a large table that doesn’t fit into a single page, you should repeat the title and column names after the split.

If your data is likely to come with uncertainties (for example, human reaction time), you can specify them in footnotes. You should also indicate equipment precision in column headings.

The analysis section of your Biology IA shows how you have used both qualitative and quantitative methods to support your arguments as well as identified and justified any discrepancies or errors in your data.

For starters, pick a sample of processed data to explain your calculations. You need to provide the equation you used and track each step to demonstrate how you converted raw numbers into analysed data. You should do it for every type of calculation (i.e. for averages, the volumes of gas obtained, etc.).

The rest of your results should be organised into fully labelled tables of calculated/processed data.

Next, you need to use this data to create 1-2 graphs with appropriate formats (for instance, bar, line, or scatter plots). All graphs must have titled axes with units and a figure legend. Below the graph, you should provide a description of trends.

It is more than likely that your data will feature uncertainties and errors – don’t try to hide them. In fact, you need to show that you understand, have reflected on, and can explain them. Best-fit lines and error bars can help you indicate these uncertainties and deviations. To maximise your final IA score, you should explain whether they are significant (how you know this), and how they impacted your results.

This section summarises the results of your experiment and answers your research question.

To begin with, provide your research question one more time to remind the reader about the aim of your experiment.

Then explain the trends obtained from your data, particularly within the graph. Make sure to be specific in your explanation. For example, instead of simply saying “temperature affected enzyme activity,” state something like “enzyme activity increased from a rate of 0.2 micromoles of substrate hydrolysed per minute at 20°C to a peak rate of 1.5 micromoles per minute at 40°C. This indicates a positive correlation between temperature and enzyme activity.”

Based on these conclusions, provide a clear answer to your research question and evaluate the extent to which it was answered. Did you achieve a complete answer, was it partial, or maybe you failed to confirm your hypothesis altogether? If you encountered any unexpected data points in your experiment, discuss these anomalies and suggest reasons for their occurrence.

If possible, you should compare your experimental values with established literature values. Cite your sources and explain how your findings align with or deviate from existing knowledge.

Finally, you need to discuss the impact of uncertainties associated with your measurements. Were these uncertainties significant to your experimental values? For example, a measurement of 10 grams with an uncertainty of ±0.01 gram is much more precise than an uncertainty of ±1 gram.

The final element of your Biology IA structure is supposed to demonstrate your critical thinking skills. In particular, it focuses on the strong and weak sides of your experiment.

We recommend that you identify at least 3 weaknesses or challenges in your experimental design, such as a lack of controls or a limited number of trials. Point out which errors were systematic, random, or human. Explain how each limitation impacts the quality and interpretation of your results.

If you provided error bars, ensure to explain what they demonstrate.

The next step is to propose at least 3 changes to improve the quality of your experimental design and data analyses. Those can include additional controlled variables, more replicates, different measurement techniques, increased precision on equipment, etc. Explain how each suggestion would specifically refine the experiment.

The last page of your IB Biology IA is a list of all the sources you utilised (textbooks, research, academic papers, etc.). You need to stick to the citation style recommended by your school.

Need Help to Write Biology IA? TutorsPlus are at Your Disposal

These were our suggestions on how to write Biology IA based on the new syllabus (the first assessment in 2025).

With 20% of your total grade, IB Biology Internal Assessment is a crucial aspect of your academic journey. It’s an opportunity to demonstrate your skills and improve your understanding of Biology. To ensure your IA report brings you the grade you hope for, you need to approach it with dedication, thoroughness, and a commitment to scientific excellence.

This journey can be quite stressful, but you don’t have to face it alone. At TutorsPlus, we understand the significance of your Internal Assessment and are here to support you every step of the way. Whether you need assistance in selecting a perfect topic, refining your methodology, or reviewing your biology IA structure or its content, our knowledgeable IB Biology tutors (who are simultaneously experienced teachers and examiners) are ready to guide you towards success.

Don’t hesitate to reach out to us for expert help and assistance. We are available at +41 022 731 8148 or [email protected]. With TutorsPlus by your side, you can turn your Internal Assessment into a remarkable achievement.

Sara has been an education consultant for TutorsPlus for 15 years, and is an expert on international IB education.  She is also a parent of two lively children.

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IBDP Biology

Internal assessment (ia) tips.

“Think about your method like a recipe. It should be easy to follow.” Author: Matthew Bowen Trained in the UK by PGCE following a degree in Biochemistry and Microbiology with over 10 years of qualified teaching experience. IB Examiner for over 5 years.

Navigate the IB Biology IA Tips easily by clicking the section icons below.

Personal Engagement

Exploration, communication, requirements of internal assessment (ia).

The internal assessment (IA) for Biology is a scientific report which explores a research question (RQ) written by the student. The requirements for the IA are the same regardless if you are studying at standard or higher level and is worth 20% of the final grade in both cases. In total the IA is marked out of 24. The breakdown is shown below along with tips and points for consideration for each of the criteria areas.

Important: Visit the official IBO page for the most updated information about this subject.

[2 marks, 8%]

A rationale developed in the exploration is good and supports the justification. the danger is personal engagement can be presented as a separate section which is a waste of time and space and is irrelevant..

Many candidates write this as a separate section, but it really does not need to be. It is marked on the essay as a whole not based upon an invented story. The examiner is unlikely to believe if your IA is sent off as as part of the sample. It is better to use this valuable space to instead focus on the report. Personal engagement may sometimes be reflected as your rationale or how you have designed the experiment. The danger is personal engagement can be presented as a separate section which is a waste of time and space as it is irrelevant.

[6 marks, 25%]

A good method can be followed from start to finish simply and result in similar outcomes to those that you obtained when doing it. Make sure you also plan to collect qualitative data as well as quantitative.

Setting out a clear and well thought through research question is vital for setting the entire report. State the research question (RQ) early and justify why it is suitable.

Use plenty of sources in writing your background information and refer back to them later when supporting any conclusions you draw. These sources can be textbooks, journals, websites, interviews etc. Ensure that they are properly referenced according to which ever referencing system you are using. This is not stipulated by the IB as they just state a system is used consistently, but most schools will have one they follow and insist you use. If you have a librarian, they can be invaluable in supporting you to reference correctly.

Always avoid the word amount . It is a vague word with little place in scientific writing. Be more specific, use words such as volume or mass in place of amount.

Think about your method like a recipe. It should be easy to follow. Hence numbered steps, all values for measurements and pieces of equipment are clearly stated to the reader. For example, if baking the first couple of steps may read:

• Weigh out 200g of plain flour using a scale. Add into a bowl.
• Add 200ml of milk measured using a 1000ml measuring jug.

There must be consideration of safety, ethical and environmental issues. All three of these must be shown to have been explored. This may just be that it is stated there are no major issues, this still shows these areas have been considered to fulfil the criteria. Remember a hazard is what could cause a problem and the risk is the probability of that happening. Do not confuse the two. If you do any sort of microbiological investigation the risk assessment will need to be carefully carried out and presented.

If you are not proficient in drawing a graph with excel or other graphing software, then it is best to hand draw them on graph paper. This will result in it taking longer to produce but is likely to result in a much clearer graph which includes all the components that would be expected of a high-quality graph. Common errors include issues such as gridlines being too widely spaced, missing axis labels or uncertainties and inappropriate lines to represent trends.

If you are doing calculations, you need not show all of them. One as an example is sufficient. Some calculations such as standard deviation may have been done using excel or other software. In this case the calculation need not be shown but it can be stated they were calculated on excel and the formula provided.

In this section further research should be used to support the explanations given behind conclusions and explore the hypothesis.

Ensure you refer back to your research question and hypothesis in the conclusion. You can not accept a hypothesis only support or reject it. The limited data you have can’t prove anything so as with amount earlier – avoid this word at all costs. If you have done statistics and have a null hypothesis also clearly comment on if this is accepted or rejected.

In this section further research should be used to support the explanations given behind conclusions and explore the hypothesis. Data from other scientific experiments or published theory around the topic will support findings well and link your research to the scientific context.

In concluding also mention any qualitative data you obtained and how it supports your overall conclusions. This is often overlooked.

Do not forget to also include strengths in your evaluation. They are clearly stated in the criteria and thus must be addressed.

It is generally a good point to say that the number of repeats could have been increased to increase reliability. In addition, explore the intervals between values or intervals for your independent variable it often could have been smaller increments.

[4 marks, 17%]

You may find it more suitable to write conclusions after the evaluation have considered what the major areas of weakness were and how this may affect the conclusion that can be drawn..

This certainly should not be a section and is based holistically on the report written. The structuring is a large part of this. The criteria can be easily fulfilled by simply following a structure that cover the areas in the way they are set out by the IA criteria. You may find it more suitable to write conclusions after the evaluation have considered what the major areas of weakness were and how this may affect the conclusion that can be drawn. The IB has not dictated a set structure for this but states that is should be well structured and clear. In the subject guide the section for internal assessment useful for students can be found from pages 154 – 158, with communication being on page 158.

Learn how to subscript and superscript in whatever word processor you use. Symbols such as O 2 and Cu 2+ are often not properly formatted and so do not meet the accepted scientific conventions. The same goes for o C. This often is written as degrees Celsius or even worse as just degrees. This is very poor scientific writing and done repeatedly will result in the loss of communication marks.

Consistency in decimal places is important. All results should be to the same number of decimal places and the mean of them only to one more decimal place if suitable. Whole numbers such as, for example a number of leaves should not have decimal places in the mean but be rounded to the nearest whole number.

The guidance is 6 to 12 pages not including any appendices. This however does not mean that you can just put all tables etc as an appendix. You could run the risk of these being excluded from marking if you do so. Try to be concise in your writing only including relevant information to support the research question you have devised. The 6 to 12 pages does also not mean it can be font size 8. Generally, go for a font size of 11 as suitable size that would be readable for teachers and examiners if your work is included in the sample sent to the IB.

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July 26, 2023

Ace Your Biology IA (HL): A How-to Guide

The Higher Level (HL) Biology Internal Assessment (IA) is a crucial component of the International Baccalaureate (IB) program. It allows students to delve deep into a scientific topic of their choice and showcase their research and analytical skills. In this guide, we will focus on the preliminary pages of the Biology IA, specifically the Title Page and the Content Page, which lay the foundation for a well-structured and successful IA.

Preliminary Pages

Generally, in a HL Biology IA , these pages refer to the Title Page and the Content Page. They come before the actual IA sections and write-up and usually do not require a page number.

Many IB students tend to place these pages on the last of their Biology IA to-do-list. However, we would advice that you do it first.

The Title Page is more than just a formality; it sets the tone for your entire IA. It should contain the following elements:

• Title (e.g. “A study investigating…”)

A clear and concise title that reflects the essence of your study, such as “A Study Investigating the Impact of X on Y as Shown by…”

• Research Question

It has to include both the dependent and independent variables.

• Relevant details such as the scientific name of the organism (if applicable), units, time, and location.

Content Page

The Content Page serves as an organized outline of your IA. It should include the following sections:

• Title and Research Question
• Introduction
• Background Information
• Variables (Independent, Dependent, Controlled, and Uncontrolled)
• Preliminary Experiment (with a focus on its relevance to the main experiment)
• Risk Assessment

Processed Data

• Analysis (including statistical calculations and graph details)

Bibliography

The IA Title and Research Question  

Identify a broad topic statement, ensuring that your research question is stated and includes both the dependent and independent variables. For example, What is the effect of X on Y as shown by… ? Your research question should include the following, where appropriate:

• The organism (if appropriate) has a scientific name

Including the following will allow you to effectively convey clarity in your research question , and thoroughly explain what you will be investigating .

Introduction and Background Information 

Introduction:

Your introduction is rooted in background information about the organism and or the topic that you will be investigating in your IA. You should demonstrate strong personal engagement by a statement of purpose.  For instance, you would avoid using cliche phrases such as “I have always loved..”, but rather opt for phrases that clearly illustrate your passion with the real, outside world, or your genuine reason for choosing the topic that you will be investigating.

Background info: 

Go on to enhance your understanding of your research question while ensuring that your background information is:

• Within context of the range of independent variables
• Within context of the dependent variables being used
• In-text cited, based on the referencing systems used in your school (e.g. Harvard/ MLA referencing) 
• Supported by a preliminary experiment through the inclusion of a short paragraph about how it was carried out, to show your clarity on how you would conduct your main experiment.

While conducting a preliminary experiment shows great engagement, many students do not do it/are not able to carry one out for various different reasons. If you have not carried out a preliminary experiment, research and describe the following instead :

• Range and intervals of your independent variables
• How you will be measuring your dependent variable

Null hypothesis : 

“The null hypothesis is a typical statistical theory which suggests that no statistical relationship and significance exists in a set of given single observed variables, between two sets of observed data and measured phenomena” (“Null Hypothesis – an Overview | ScienceDirect Topics”).

For example,

“There is no statistically significant association between X and Y .”

Alternative hypothesis : 

Your alternative hypothesis is an alternative theory that is suggested with direct polarity to the null hypothesis.

“There is a statistically significant association between X and Y .”

• Independent, dependent and controlled variables are clearly stated
• Ensure to have at least 5 intervals and at least 15 repeats for each interval
• Explain how and why you are using those variables, how certain variables may not be controlled, and how you minimise the effects of these to suit it to your experiment effectively

Ensure that all apparatus, chemicals and solutions are listed and / or shown in a diagram if relevant and all apparatus used are relevant. (Not an obligatory list, can be given in the method)

Preliminary Experiment 

The Preliminary Experiment is often overlooked, but it holds immense value in shaping your main investigation. Students can improve this section by linking it seamlessly to their IA. Describe how the preliminary experiment influenced your methodology, analysis, and decision-making process. If you haven’t conducted a preliminary experiment, research and discuss the range and intervals of your independent variables and the method of measuring the dependent variable.

Your method section demonstrates that you have sufficient data that has been collected, and that you have thoroughly reflected on each method of control.

Ensure to :

• Outline method in a step by step, list-like format
• Reflect on every controlled variable in the method while explaining
• State that you have : “Repeated method ____ for verification” at the end of every section.

Risk assessment to ensure safety

Include a risk assessment of apparatus and chemicals and show awareness of:

• ethical issues – eg handling of animals
• environmental issues – eg  impact on field sites

Once you have collected your raw data, the next step is to process and organize it for analysis. The Processed Data section is where you present your data in a structured manner, making it easier for readers to interpret and draw conclusions. Follow these steps to effectively present your Processed Data:

• Data Organization Begin by organizing your data in a clear and systematic way. You can use tables, charts, or graphs, depending on the type of data you collected. Ensure that each piece of data is properly labeled and includes units, where applicable.
• Data Manipulation In some cases, you might need to manipulate the data to calculate specific values or derive meaningful insights. Show your calculations and formulas used for any data manipulations, and explain the rationale behind these transformations.
• Averaging and Standard Deviation When presenting numerical data, consider calculating the averages and standard deviations if relevant. These statistical values provide insights into the central tendency and variability of your data points.

The Analysis section is where you interpret your processed data and draw meaningful conclusions from your findings. To conduct a comprehensive analysis, consider the following steps:

• Statistical Calculations Based on the nature of your data, choose appropriate statistical calculations to support your analysis. Depending on your research question and data type, you might use measures like mean, median, mode, range, standard deviation, t-test, chi-square test, etc. Mention the statistical methods you used and why they are appropriate for your investigation.
• Graphs and Visualizations Graphs and visualizations are powerful tools to represent your data visually. Create clear and accurate graphs that effectively illustrate the trends, patterns, and relationships present in your data. Choose appropriate graph types, such as bar graphs, line graphs, scatter plots, or pie charts, based on the variables you are analyzing.
• Data Interpretation Thoroughly interpret the patterns and trends depicted in your graphs and statistical results. Explain the significance of any relationships observed and how they relate to your research question. Use evidence from your processed data and refer to relevant scientific principles to support your interpretations.

Ensure that your analysis section includes sufficient correlated qualitative and quantitative  observations, anomalies that have been clearly pointed out and explained, statistical tests and graphs that explain the data collected.

The figure below is an example graph taken from a model IA, where the student has clearly presented information in a graph.

In the Evaluation section, critically assess your investigation and methodology. Address strengths and weaknesses, reflect on potential sources of error, and suggest improvements for future studies. Consider the following points for a well-rounded evaluation

• Methodological Considerations Discuss any limitations or challenges you encountered during your investigation. Analyze how these factors might have influenced your results and propose ways to mitigate potential errors.
• Reliability and Validity Reflect on the reliability and validity of your data and methods. Identify factors that could have impacted the accuracy and generalizability of your findings.
• Sources of Error Be honest about any sources of error that might have affected your results. Consider experimental errors, sample size, or unexpected external factors that could have influenced your outcomes.

Evaluation : 

• Conclude by making explicit reference to the research question. In other words, your conclusion should directly answer the question : “Does the data answer the Research Question?”
• State if your null hypothesis is accepted or rejected
• Refer to the graph and data points to clearly demonstrate your understanding and strong conclusion
• Compare the conclusion with published data and predictions 

( A good tip here is to put your graph in and next to it put a graph from a textbook or website. Can you either explain any differences or relate it to scientific theory?) 

• Strengths and weaknesses of your investigation
• Further extensions that could have been carried out. 

Figure 1 : Model student IA graph 

The Conclusion section is where you summarize your key findings and directly address your research question. Follow these steps for an effective conclusion:

• Restate the Research Question Begin by restating your research question to remind readers of the central focus of your investigation.
• Answer the Research Question Clearly state whether your research question was supported or rejected by the evidence presented in your analysis. Use your processed data, statistical calculations, and graphs to support your conclusion.
• Relate to Scientific Theory Connect your findings to established scientific principles or theories. Discuss how your results align with existing knowledge in the field of biology.

Finally, provide a comprehensive list of all the sources you used in your research. Include academic papers, textbooks, websites, and any other references you consulted. Use the appropriate citation style, such as Harvard or MLA, as required by your school or institution.

Sample IA marked and annotated :

http://xmltwo.ibo.org/publications/DP/Group4/d_4_biolo_tsm_1408_1/pdf/investigation_1b_e.pdf

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• Sep 15, 2023
• 15 min read

Ultimate guide to the new IB scientific investigation (2023 syllabus)

Updated: Sep 15, 2023

Three DP experimental sciences (Biology, Chemistry, and Physics) have a new syllabus starting in 2023 (first assessment in 2025), and the new Environmental Systems and Societies will begin in 2024 (first assessment in 2026). Apart from significant content and assessment updates, the new scientific investigation (formerly known as the internal assessment, or IA) also received a major facelift. If you're starting one of these courses this fall, now is a great time to start thinking about your research paper and what you can do to prepare for it. For those of you still on the old syllabus, you'll find plenty of relevant advice here as well, so stick around!

Table of Contents

Use the links below to jump to the relevant sections.

What's new?

Time required, number of students, assessment criteria, research design, data analysis, choosing a research question, types of investigations, proposals and preliminary experiments, writing the investigation, introduction, background research, safety and ethical concerns, assumptions, data and analysis, discussion and conclusion, role of the teacher.

Let's get the most obvious question out of the way first. What exactly has changed with this new assessment? Well, the most obvious difference is the name. Previously known as the internal assessment (IA), we are now calling it a scientific investigation, which is how I'll refer to it for the remainder of this article. Personally, I'm thrilled with this change since I end up spending a whole class period each year just trying to explain what the IA is and what it isn't. In case you don't know, It's an internally assessed and externally moderated experimental investigation chosen by each student for each of their science courses. Does that clear things up? No? Well, here's a handy summary video and table comparing the new and old assessments.

Summary of the new scientific investigation

Notably, the length has been standardized to less than 3000 words. This is a positive change as the previous page limitation discouraged students from including images and graphs in their reports. It also caused issues where students would manipulate their font sizes and layouts to stay within the page limit at the cost of readability. Also note that data tables, citations, headings, etc. do not count toward the total word count.

The 10 hour timing has not changed, although it continues to be misleading for students. This allocation is meant to include the time your teacher spends explaining the investigation, time for researching, experimental time, and time to meet and discuss feedback. These all take place during the school day, of course, and if that's all you do, your report will probably fall far short of where it needs to be. In reality, the scientific investigation probably takes most students upwards of 40 hours to complete, with the vast majority of work happening outside of class. That's a major investment for a course that's only supposed to have 110-180 hours of syllabus content (for SL and HL, respectively).

I'm not quite sure what to make of this change. The IA was always an individual assessment that could only involve shared data collection in rare cases. Now the potential for collaboration is being touted by the IB, although since students are required to have different research questions, the investigations would generally end up being very different anyway. Still, if students insist on working together (possibly because their procedures are particularly complicated or time consuming), the IB gives three examples for how collaborative investigations should be differentiated.

Each student in a group uses...

…the same dependent variable but chooses to investigate the effect of a different independent variable.

…the same independent variable but chooses to investigate the effect on a different dependent variable.

…different data within a larger dataset or database.

Despite the potential for collaborative projects, I would generally recommend that most students stick with doing their own investigations to avoid any potential complications.

Major changes here. The "communication" criteria has been absorbed by the other sections, and the "personal engagement" marks have been removed entirely. My guess is that these assessment criteria were determined to be too subjective, something external moderators and the IB would prefer to avoid. I tend to agree, for the most part.

Also, it drives me nuts that the IB didn't take this opportunity to make each section worth 5 marks instead of 6. This would have put the total marks at 20 - the same as the final grade percentage for the scientific investigation. It's such a logic fail, and it makes it unnecessarily difficult for students to calculate their predicted grades (which we all know they do obsessively).

Below are the new assessment guidelines for each of the four major criteria. These are directly from the IB documentation, and they are the same for all science subjects.

Now that you understand what the scientific investigation is all about, it's time to narrow down a research question. You might think that this would be easy, but many students struggle for weeks or even months to come up with a reasonable topic for investigation.

A basic template for a research question could be:

"What is the effect of ( independent variable ) on ( dependent variable ) in ( test subject or condition )?"

Here are two examples:

What is the effect of acidic soil pH on the mass of tomatoes grown in planters ?

What is the effect of different oil-based lubricants on the coefficient of friction of skateboard bearings ?

Aside from the basic format of your research question, here are some additional tips to get you on the right track:

Make sure your research question identifies both the independent and dependent variables. Be as specific as you can (include measurement quantities, species names, etc.), even if starts to sound kind of ridiculous.

Choose a dependent variable that is easily measurable and provides reliable quantitative data. Recall that quantitative data is numerical, as opposed to qualitative data which is descriptive.

Avoid doing any of the prescribed practicals, including closely related experiments. Neither your teacher nor external moderators will be impressed by your ability to carry out an experiment that you would be required to perform anyway.

Don't try to be too original. Aside from the prescribed practicals, everything else is fair game. Just make sure that you don't have the same research question as another student in your class. You can always tweak a familiar experiment to make it more interesting or unique.

Choose a simple experiment. It's better to do a thorough job on something you understand rather than trying to impress people with a complex investigation you can't handle.

Choose a topic you care about. It's always easier to stay motivated when you actually care about the outcome. If you need ideas, try flipping through the textbook to find topics that you enjoyed learning about in class. Then seek ideas related to those topics.

Consider your timeline. When is the investigation due? If you have only a few weeks, you probably shouldn't plan to grow plants or something similarly time consuming. Also, remember that the experiment itself is only a small portion of the investigation. Give yourself enough time for research, writing, analysis, and feedback.

Below are the five types of explorations the IB considers acceptable for the scientific investigation:

Hands-on practical laboratory work

Use of a spreadsheet for analysis and modelling

Extraction and analysis of data from a database

Use of a simulation.

The majority of students will perform a hands-on practical experiment, either in the lab or in the field. A simulation could potentially be used, but it is considered an inferior form of experimentation since it is based on many assumptions and models of real-world conditions. A student can justify the use of a simulation in cases where it would be too time-consuming or expensive to perform the experiment for real. It can also be used as a part of a larger investigation.

The use of a spreadsheet is pretty much expected for all data-based investigations, so I wouldn't count that as a separate type of investigation.

The final type of investigation would be a pure data analysis (or meta analysis). In this case, the student doesn't actually carry out an experiment themselves, but instead collects data from a variety of sources to investigate their research question. As with simulations, this is generally considered inferior to hands-on experimentation unless the student is very good at statistics and has access to a LOT of data. This type of investigation was more acceptable during the distance learning period associated with the pandemic, but now that face-to-face learning has mostly resumed, I would avoid this type of investigation under most circumstances.

Once you have a research question and a basic plan for your investigation, the next step would be to run it by your teacher to identify any potential problems. This might seem annoying, but you really don't want to find out that your research question is flawed after you've invested hours of your time (and sometimes money).

If your plan has been approved but you still aren't sure how to proceed, it's time to perform some preliminary experiments. Doing a few informal trials will help you quickly identify problems with your variables and what quantities you should use for your actual experiment. It will also assist you in writing the procedure for your formal investigation. The good news about these preliminary experiments is that you don't have to record much. It's usually enough to simply state that you used them to inform your planning.

Next up is the research phase. Depending on your topic, this may be done before, after, or during the other parts of your investigation, but ideally, your research should continue throughout the scientific process as you identify new problems and ideas to explore.

Your research will roughly break down into three stages, as follows:

Initial research - This includes any searches you do to help generate a research question or figure out what your variables might be. It should also include a brief look through existing research to see how much literature exists on your chosen topic. If you can't find much in the way of resources, it could mean a few things. It's possible that your research question is very original, in which case you will have a difficult time comparing it to other studies or supporting your findings with evidence. Unfortunately, the most likely alternative is that your research question isn't very good, which is why no one else has attempted it before. Don't feel discouraged if you find many experiments that sound just like what you are planning to do. This is a good thing, as it means you have a lot of material to work with! Once you are finished with the initial research, you are most likely ready to write your introduction.

Background research - This is meant to include everything you and your intended readers will need to know in order to complete or understand your investigation successfully. It is likely to be the most extensive research you perform, and the relevant sections of your report content should reflect that. For many investigations, this ends up being 1-3 pages in length. You will need to define new terminology, explain concepts and theories, and refer to existing studies. You will also need to use your background research to inform your procedure and explain your assumptions for the experimental portion of the investigation. Sometimes while conducting background research you will stumble upon an article or experiment that is a perfect match for the topic you are exploring. That's great, but don't rely too much on a single source! Keep exploring until you have a variety of studies and perspectives to work with. When your background research is finished, you can begin writing the procedure and then carry out your experiment.

Evaluative research - At this point, you've completed your experiment, made the necessary measurements, and performed a detailed data analysis. Unfortunately, you haven't explained anything yet. That's what evaluative research is for. You'll need to delve back into the literature (in some cases using the same sources you identified earlier) in an attempt to explain the patterns and peculiarities in your data. This research is straightforward because you know what you're looking for, but it's also difficult because you might not find the answers. That's just the reality of science! It's ok if you can't explain everything you observed in your analysis, but you should at least be able to offer suggestions based on your findings.

The design portion of the scientific investigation comes first and includes the introduction, background research, hypothesis, variables, materials, and procedure. Following experimentation, you can then proceed to include the data analysis, conclusions, and evaluation sections. It sounds extensive, but if you take your time and follow along with the recommendations below, it's actually fairly straightforward. Let's go through each section in a bit more detail.

The introduction for the scientific investigation should include several pieces of information. Firstly, you should introduce your topic, including why you chose it and why it is important to you. If you can, identify the purpose of the investigation by linking your research question to a real-world problem or issue. It may be worth providing some facts or figures here for context. Next, briefly describe the procedure you will use in a sentence or two, along with some justification for why you chose this method. Conclude the introduction with a statement about what you hope to learn through this investigation.

See the research section described above.

State the null and alternative hypotheses in the clearest, simplest way possible. You shouldn't need more than a sentence for each of them. You might recall that the alternative hypothesis is the relationship you are expecting to observe, while the null hypothesis is that there is no relationship between your variables. Use your research question to help you construct the hypothesis, and be sure to include a scientific explanation for the relationship as well.

This section is more of a list than a paragraph, but it is still quite important. Simply state your independent variable (the one you will modify) and dependent variable (the one you will measure). Include the units you will use for those variables as well. Note that you should have just one independent and one dependent variable. There are rare exceptions to this, but that's a good general rule to follow.

After that, make a list of all the controlled variables for your investigation, which should include as many as you can think of. If you have a long list of variables, you may want to format them in a table for clarity.

This is perhaps the easiest section in the entire report, but there are some details that students often forget to include. For starters, make a list of every item you will need to complete the investigation. You should be as specific as you can, including the quantities, sizes, brands, and model numbers of all equipment used. You do NOT need to include yourself or anyone who helped you perform the investigation, but you should include anyone who was a participant or test subject. For privacy reasons, however, do not use any names or identifying features. All chemicals used for the investigation should be listed here, with the exception of water, which is assumed to be freely and readily available to anyone.

Apart from the materials themselves, there are some other things you should add to this part of the report if you want to receive top marks. One of these is a description of the safety and ethical concerns. If you think there are no major concerns worth mentioning, write that! For this particular section, pretend your audience is really stupid. Advise them not to eat or drink anything while doing the experiment. Remind them to wear gloves, goggles, and a lab coat if necessary. Tell them how to dispose of waste properly. The IB will expect to see something here, so don't disappoint them.

Another section that can often be found just prior to the materials list is a description of the assumptions made during the design and planning process. This will give you a chance to explain your choices for the upcoming materials list and procedure which might be hard to figure out without some context. It may also include equations or references used in the procedure. If you used people as test subjects, describe how they were selected and what they were told. Now is also a good time to justify the number of trials and conditions tested in the procedure.

I've seen students write this section in paragraphs, but I would advise against that. Instead, treat it like a recipe, with short, numbered steps and clear commands. Be specific so there's no room for error. Have a few friends read it to make sure they can understand the process. Particularly complicated procedures are best accompanied by diagrams or photographs of the experimental setup.

It used to be a big no-no to include personal pronouns in a scientific investigation, but the stance on this is has become more relaxed in recent years. Still, some teachers and moderators may look down on informal writing styles, so why risk it?

The data from your experiment should be organized in tables, including units and appropriate titles. If there is a lot of raw data that would take up a page or more, create an appendix for it and include only a summary table in the main report. Such a table would contain mostly totals and averages that could be used to create graphs, not individual data points.

Create your graphs using Excel and make sure you choose the correct type to represent your data. If you want to show how something changes over time, a line graph is probably best. For visualizing the relationship between two variables, a scatter plot will be most appropriate. Many students don't realize how much Excel is capable of and will not take the time to customize their graphs. Be sure to include descriptive titles, axis labels, units, and a legend (where appropriate). Trend lines and error bars should also be included, both of which can be added automatically with just a few clicks. Error bars in particular are often overlooked, but they provide useful insights for analysis.

Any equations or statistical tests used in the analysis should be shared here. Sample calculations are worthwhile too, except for very simple operations such as determining a mean value.

The last part of the analysis should be one or more descriptive paragraphs outlining the major trends in the data. This might include correlation and regression, ranges, min/max values, % increase/decrease, outliers, statistical significance, and so on. For now, your goal is simply to identify anything that might be important using your own numerical evidence. Don't attempt to explain any of your findings just yet. That will come later.

By this point many students are running out of steam and often rush to the conclusion without including a proper discussion. Don't make this mistake. You should absolutely report whether or not your hypothesis was supported (even partially), but be very careful with your wording here. The hypothesis should never be "confirmed" or "proven" because science doesn't deal in certainties. At best, your experiment may suggest a correlation between variables. If the data is inconclusive, state that.

I should take a moment here to discuss so-called "failed" experiments. Many students panic when their data yields no obvious relationships or their hypothesis is rejected. Let me reassure you that you cannot be deducted marks for this. In fact, this happens more often than not in science and you should not feel bad about it or attempt to cover it up with fancy or deceptive language.

The rest of the discussion should be your attempt to explain the trends you identified in the data analysis using research and logic. This is where that evaluative research I mentioned earlier comes into play. Don't be afraid to admit that you can't explain something. That's not at all uncommon. In almost all cases, you should mention that further research and experimentation should be conducted, and you can be as descriptive as you like in what that might entail.

The final paragraph of this section should mirror the introduction, so refer back to that for guidance on how to proceed. You should reflect on your stated purpose and the extent to which you have answered your research question. You should also make a statement about how your findings could potentially be applied to real-world problems or situations.

This section is meant to be an honest evaluation of your methodology, not the results of your experiment. Focus on specific problems and limitations instead of generic ones like insufficient sample size or measurement error. You should also comment on the relative effect your investigation's weaknesses may have had on the results, with justification. Was the problem significant, moderate, small, or negligible, and why?

For each area of concern you identify in the evaluation, you must also provide realistic solutions. Many students prefer to present their evaluation in table format, and I tend to agree that this makes for improved clarity.

It should go without saying that you must properly cite your sources for all facts and figures utilized in your investigation. The IB makes no recommendations as to the citation style of the scientific investigation, so just use whatever standard format your school requires. If in doubt, APA is very common among the sciences. Make use of in-text references or footnotes, depending on the format you choose. The important thing is to be consistent.

Surprisingly, the IB issued a recent statement regarding the approved use of AI in their assessments, including ChatGPT. They do not, however, consider content generated with AI to be the student's own work, meaning that you must paraphrase and cite AI images and text as you would any other source. Also, keep in mind that the information ChatGPT and other platforms provide may be highly inaccurate or entirely false. Proceed with caution, but don't be afraid to put AI to work to help you structure your investigation or analyze your text.

A table of contents and cover page are not required, and you should ensure that your name, school, and other identifying details are not included anywhere in your report. The entire investigation should be single-spaced, and although it isn't a strict requirement, 12-point Times New Roman font is fairly standard.

Your teacher is there to support you with your investigation, so by all means take advantage of their guidance when necessary. Generally teachers will assess one draft version of your report and provide detailed written or verbal feedback, but you can always ask for further assistance. Just keep in mind that you are one of many students and that their time is limited.

Phew! If you made it this far, you've probably gathered more than enough information to get you on the right track for your scientific investigation. The 2025 syllabus is still very new and there simply isn't a lot of quality information out there yet, but I hope you found this article informative. Good luck!

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12 Examples and Tips for IB Biology IA

May 4, 2022 | IB subjects

IA is one of the many things IB students struggle with, but some might feel that writing the IA in Biology is especially confusing since it covers broad topics. This post is for those who are having a hard time coming up with a topic, are worried about writing the IA in Biology overall, or are interested in Biology but not so sure about taking it because of IA. An overview of the subject IB Biology can also be seen in a previous post: Exam Strategy for IB Biology (HL/SL) .

1. Overview of Biology IA

Both HL and SL students are expected to write an IA ( Internal Assessment ) in Biology which accounts for 20% of the final grade . The IA in biology is expected to be a 6-12 pages long report about an investigation a student carries out based on their own hypothesis.

1.1 IA Criteria

HL and SL share the same IA criteria and it’s important to understand the criteria before and while carrying out the investigation for your IA. (Reference: Biology Teacher Support Material )

2. Examples of Biology IA Topics

Many IB graduates have kindly answered an online survey by MakeSensei and given examples of IA topics in IB Biology. Some of them are RQs (Research Questions), so you might want to see the pattern of how they make RQs for your future IA.

• What is the effect of exposure to different concentration of sodium chloride solutions for different duration time on the germination percentage, mean germination time, and relative injury rate of Ipomoea aquatica?
• Lactic acid experiment in milk
• What is the effect of sodium chloride concentration (0.0, 0.4, 0.8, 1.2, 1.6, and 2.0 %) on the rate of hydrolysis of 1.0 % starch solution by 2.0 % ɑ-amylase (Bacillus subtilis), measured as the rate of decrease in absorbance value (Au s–1), using Spectrophotometer Vis at 434.2nm?
• Protein-digestive enzyme
• What is the effect of fertiliser quantity on evening levels of dissolved oxygen in river water samples over a period of two weeks?
• An Investigation into the Effect of Different Types and Concentrations of Pesticides (Orthoran Acephate, Kadan Safe, Kadan Plus DX) on Seed Germination: Observing Plant Growth of ErucaSativa, Brassica Oleracea, Lepidium Sativum and Perilla Frutescens
• An investigation into the effect of sodium chloride on plant germination and its growth.
• (Title: How to make delicious natto) RQ: What is the effect of pre-soaking time of soybeans, 0.00, 3.00, 6.00, 9.00, and 12.00 hours (±0.05 hours), on the length of threads between separated fermented soybeans (natto) measured by a clear plastic ruler (±0.1cm)?
• Effect of light intensity on the travel activity of a Physella acuta
• Investigating the effect of concentration of the salt solution on germination and growth of cotton and spinach seeds
• Investigating the correlation of the length of knee roots of a mangrove and the number of holes crabs make in the given area
• Effect of temperature on denaturation of albumin protein

3. Tips for Biology IA

3.1 Set Appropriate Independent/Dependent Variables

In order to carry out the investigation with sufficient sample size and trials, there needs to be independent and dependent variables that are both appropriate in terms of the purpose of your investigation. If you want to find out the relationship between X and Y (how X influences Y), then your independent variable should be X and your dependent variable should be Y. Both variables should be measurable , meaning quantitative, to allow various statistical analyses. But having qualitative data is valued in discussion as well.

3.2 The More Data, The Better

It is known that you should have at least 25 samples of data for your Biology IA, but let us explain why. While having multiple trials is necessary for the investigation, each trial should also have multiple samples. Therefore, 5 trials with 5 samples each make up 25 samples in total. Having said that, your sample size is up to you, and having more than 25 samples would only make your data more robust . But make sure you have enough time and energy to process the whole data.

3.3 Use Appropriate Secondary Sources

Doing background research on the field you’re focusing on in IA is required to back up your hypothesis, discussion, and conclusion. A lot of people use secondary sources (sources that are not first-hand) and most often through the internet. But, using Wikipedia or personal blogs would not be appropriate for your IA because they may not be reliable, accurate information. Instead, you might want to use these websites to search for previous academic articles and journals.

• Google Scholar
• The World Factbook  (provides you data about the country of your interest)

3.4 Don’t Forget Annotations and Citations

• Annotations

An annotation is a short comment written near an image to give an explanation. Annotations are necessary when the image and its title don’t give enough explanation to specific objects in the image and your word count is limited. For example, when you’re showing your method with an image of instruments, readers might not understand why you chose those instruments to carry out your experiment. To avoid such inconvenience, annotations provide more detailed information than the title and the main text.

A citation is a short version of the reference to your source and it needs to be in-text or footnote. Every time you mention something that is not original or first-hand, you need to put citation(s) to prove where that statement comes from. If you miss citations, it will be considered plagiarism and you could fail the IB. Therefore, citations are important!! You could use  Citation Machine  to create a reference list and citation for each reference (check which style is preferred by your teacher).

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IB Biology IA ideas (30+ topics) - A Goldmine You Can't Ignore.

Unleash your potential in IB Biology with our exclusive list of 30+ captivating IA ideas! Discover the secrets to scoring top marks & nail your IA now!

Table of content

Sitting in that quiet corner, sipping hot chocolate, hoping it rains IB Biology IA ideas, instead, going blank and utterly confused?

We don't want that to happen, do we? 

Choosing the perfect IB Biology IA idea is only the first step in making one's IB Biology Investigation, but definitely, the most significant. IB Biology IA Ideas won't strike out of the blue, but here's a list of  30+ IB Biology IA ideas  to inspire and stimulate your grey cells! Selecting an IBxq Biology IA idea has always been challenging! 

Before we look for IB Biology IA ideas, let's clearly comprehend the  IB Biology Diploma Programme Subject , its objectives, partwise breakdown, and what IB expects of you.

The IB IAs are essential to one's overall subject performance since they make up 20% of the final score. Internal Assessments are the perfect way to get students to put their knowledge to use by Observing, Questioning, and Investigating.   Personal engagement ,  Exploration ,  Analysis ,  Evaluation ,  and   Communication  are the criteria against which the investigation is assessed.            

The sure-shot way to ace one's IB Biology IA, or any IA, is by picking a topic that sparks one's interest. A well-planned , structured, and executed  IA has been undertaken with zeal and enthusiasm. It is all the same when choosing that one Biology IA idea from a platter full of inspiration. 

Before we dive more in-depth, you should check out our  premium IB Biology SL Notes  to own your Biology SL papers! Along with a bundle of  Past Papers , these  premium SL notes  include guides for your  Extended Essay  and  Internal Assessments  with helpful examples! You certainly want to take advantage of these! Browse  these  for more information! 

When it comes to selecting from several IB Biology IA ideas for your investigation, it is essential to note that your IA would either require you to:

• Carry out experimental research in the laboratory or
• Draw interpretation from a credible database or
• Make a detailed analysis using a simulation/modelling.

Either way, you must connect to your topic and portray personal engagement as it lays the foundation for the rest of your investigation. Proper research is a bare minimum, and the rest follows. Here's a quick summary of how you are supposed to choose an appropriate IB Biology IA idea for your report:

• Know your interest:  Go through several IA ideas to understand what all topics are in sync with the IB Biology curriculum and if something grabs your attention, hold on to it!
• Keep it specific:  The idea should be more generic and more complex. An ideal IA idea reeks of originality and leaves room for proper investigation and analysis.
• Let it be realistic:  Outline the Equipment, time, and resources to check its feasibility.

Tada! There you go! 

Now that you know how to settle on that one perfect topic, let's quickly brief ourselves on the proper planning and procedure involved in the making of an IB Biology IA:

Concise Research Question:  

Your Research Question and the Aim of the Investigation are separate sub-headings with different implications. Keep the research question brief and relevant. The Aim answers Why while the Research Question answers the What.

• It is essential to set the Research Question in the background of the chosen topic. My Background, IB expects you to briefly explain what encouraged you to select a particular topic and, hopefully, a personal story that validates your choice and engagement. For instance, if you choose to investigate how light levels affect the predation of peppered moths, you could set a background that you have gained a fascination for that species ever since it was introduced to you for some explanation in your regular classes and eventually give more scientific basis for your choice.
• Independent, Dependent variables need to be highlighted, as should the hypothesis. State your hypothesis; it is important in the context of your research. Constraints, if any, need to be mentioned as well. Remember, the Independent variable is one that you are allowed to change(just one); the Dependent variable is one that you measure as it changes with the Independent variable; all the other experiment conditions must be kept constant to ensure that the experiment is fair.
• The procedure used should be well structured.
• Tables, Graphs, etc., should be used.
• Perform the relevant analysis, consider the research question, and conclude. 
• Limitations and Improvements should be specified.

Acknowledging the safety protocols established by IB and considering the ethical aspects of your investigation is imperative. 

Focus on the question:

"If there are any ethical implications to your report, how do you plan on minimizing the environmental impact of your experiment?" 

Citing documents/web pages and giving references is another crucial aspect of your IA that needs to be taken care of. 

An important thing to note here is that although you are allowed to take inspiration from existing research, papers/journals, you are expected to give a novel perspective to the idea while producing it in your investigation.

For example, an idea inspired by how the soil pH affects seed germination could be investigated in a new light; think of other factors controlling/affecting seed germination. You could progress further in your report with a focus on quantitative data.

With all the necessary information at your disposal, it is time to present some fantastic IB Biology IA ideas to encourage you to put your thinking caps on and take on the challenge with newfound zeal! These ideas are meant to give you a little head start along this path; your final IB Biology Investigation idea is your interpretation of one.

Without further adieu, let's dive headfirst into  30+ IB Biology IA ideas  for your Biology IA Investigation!

• Reference to Course:   Molecular Biology  (Metabolism, Cell Respiration, Photosynthesis)
• Lab, Simulation-based
• Reference to Course:  Molecular Biology (Metabolism, Cell Respiration, Photosynthesis)
• Experimental 
• Reference to Course:  Cell Biology (Membrane Structure)
• Experimental
• Reference to Course:  Plant Biology
• Reference to Course:  Molecular Biology (Enzymes)
• Reference to Course:  Cell Biology
• Simulation/Modelling
• Reference to Course:  Cell Biology (Osmosis)
• Database based
• Reference to Course:   Molecular Biology (Enzymes)
• Reference to Course:  Ecology
• Reference to Course:  Microbiology
• Reference to Course:  Molecular Biology(Enzymes)
• Experimental, Simulation-based
• Reference to Course:  Buffers
• Reference to Course:  Human Physiology
• Reference to Course:  Molecular Biology(Enzymes)
• Simulation Analysis
• Database, Experimental
• Reference to Course:  Plants Physiology

These ideas are for you to start exploring and begin! Take inspiration from these and research further to land on that one idea that gets you going!

But is that it? Certainly not! 

Here are a couple of other ideas you could browse and eventually take inspiration from:

• Effect of Different Fertilizers on  Eutrophication .
• Analyzing Milk Spoilage under varying conditions of Temperature, Sunlight, etc.
• Exploring how a particular variable affects the  germination of seeds .
• Investigating the rate of oxygen production of seaweed with variation in light intensity.
• To prevent microbial growth, explore better ways to clean household items(for example - mats).
• Studying the effect of temperature on photosynthesis in Green Gram(Vigna Radiata).
• Understanding what effect different ethanol concentrations have on cell membranes.
• Studying the biology behind  Schizophrenia .
• Investigating the decay time of different  Genetically Modified Foods .
• Understanding the impact of different variables on vegetable decay/ Exploring other methods to prevent vegetable decay.

And that's that!

These little ideas will help you brainstorm and explore further the vast yet intriguing expanse of biology. IB Biology curriculum expects you to appreciate scientific problems in a global context with stimulating opportunities, and IB Biology IAs help you accomplish just that. It might seem like a lot of work, but with the right topic, you will surpass your expectations! On this note, we wish you all the very best for your IB Biology IA Journey :)

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This article will be a foundation for you to get going on that IB Biology IA Investigation of yours!  

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