AP Biology Lab Report Guidelines & Criteria

Introductory Notes: 

• This exhaustive guide endeavors to provide guidance for all typical lab report structures and practices.  In instances where a complete lab report is not required (as indicated in the lab document, aka most instances), this resource still specifies the conventions for the acceptable format and minimum structure of various components. In those instances, it is strongly suggested that you use the Table of Contents, Document Outline, and/or CMD+F to find specific elements of interest.  
• Students can expect that their teacher will refer them to this document when they have initial questions about the elements of a lab report criterion or do not complete lab report elements according to the guidelines below. If a student has questions after having read the relevant section(s) of this document, they are highly encouraged to note that in any followup questions to their teacher. Typically, you will be referred here due to concerns related to General Guidelines, Submission Guidelines or typical elements discussed in the Results section.  That noted, you may be referred here for other guidance as well.  

Rationale: 

You have conducted an experiment, have buckets of data, and have given things some thought. It is now time to communicate the results of your experiment. Formal lab reports are important (labs count for as much in your course average as exams do), and there are certain conventions that you follow when you write one for AP Biology.

In AP Biology, we use the IMRaD format when writing “full” lab reports. IMRaD (Introduction, Methods, Results, and Discussion), is a standard format for reporting the results of experiments in the scientific community. This document explains the specific details of our IMRaD lab reports. It is important that you read this document fully, and ask any questions that you have prior to submitting your first AP Biology Lab Report.

Table of Contents:

The following table of contents is provided to help you navigate the document:

AP Biology Lab Report Guidelines & Criteria

Introductory Notes:

Rationale:

Table of Contents:

General Guidelines:

Submission Guidelines:

Report Sections:

Title: What is the name of your experiment?

Introduction: Establishing a context for the lab

B. Objectives:  Establishing the lab’s purpose  

C. Research Question and Hypothesis: Establishing a question and a prediction

Methods: What equipment, organisms, or reagents did you use?

A. Materials

B. Procedure: How was the experiment conducted?

Results: What data do you have?

A. Data Collection: What information have you gathered?

B. Data Presentation: How will you represent the data you collected?

Data table specific formatting conventions:

Graph specific formatting conventions:

Drawing/Image specific formatting conventions:

Statistics:

Calculations and Data Processing:

Discussion:  What does your data mean?

A. Conclusions: What does this all mean?

B. Experimental Evaluation:

References:

Artificial Intelligence (AI) Declaration:

Appendices:

Length Considerations:

Collaboration Considerations:

Exceptions/Alterations

Additional Support:

Writing Process

Technical Help

Google Docs Help Pages:

Graphing-

Equations-

Citation/Reference Styles:

APA Style Guide:

IEEE Style Guide:

Citation Machine Reference Formatter

Generalized Report Grading Criteria:

General Guidelines:

Generally, you will be given several weeks to work on a formal lab report at the conclusion of a lab experience. This is because your teachers are kind, but also because we fully expect that the document that you submit is evidence of your best possible effort. To that end, there are a few, basic things that you want to make sure you have done prior to submitting the lab:

• Address all points of each section as delineated below.
• Proofread your lab for spelling and grammatical concerns.
• Adhere to all appropriate scientific conventions:

• Organisms are conventionally referred to by their properly formatted, capitalized, and italicized scientific names (Genus species)
• Genes and derived nucleic acid elements are italicized. Proteins are not.
• Concentrations are listed for all reagents.
• Units are always included for data.

• Go through your lab and make sure that all sections are properly and consistently formatted:

• There are no haphazard changes in font type (use a legible, non-decorative, font)  or font size (12 point is a generally accepted standard), except where you have deliberately chosen to do so (e.g. headings, titles), etc.
• Line spacing is consistent (1.5 spacing for these reports is a good sizing, though double spacing is also acceptable).
• Margins are responsible (1 inch at a maximum).
• Pages are numbered.
• While these style guidelines are inarguably nit-picky, adherence to them advertises that your work is a product of your best possible effort.

• Future Proof BONUS for close-reading future STEM Majors:  Hey!  This guide will be VERY helpful in any college report writing for STEM stuff.  Make a copy someplace and keep it for when you might need it.  

Submission Guidelines:

All labs in this course are to be submitted via google docs or other google tools. You need to create them in Google Docs on the SAS Google Suite. There are several things that you need to make sure you do when submitting your lab:

• Make sure the filename of the lab (top left corner of the document) has your name and the names of all group members in it.
• Your teacher has editor access to the document at their SAS work email address. This is easily accomplished by putting your lab in your drop folder for this course in google docs. You can also manage sharing more directly via the blue Share button on the top right of the Google Doc composition window.
• A template IMRaD document is provided for your use at this link.
• In many cases, your teacher will send you a template via doc deployment to your course drop folder. In those cases either use that document, or something that looks a lot like it. If the template is in the view folder, use the “Make a copy…” option in the file menu to make a copy for your own usage.
• If a lab has additional submission guidelines (ex. via a submission portal on Schoology, or through email), adhere to those guidelines in addition to the above.

Any Lab Report that does not follow these submission guidelines runs the risk of not being recorded as submitted or evaluated by your teacher, so it’s pretty important to follow these guidelines.

Report Sections:

Title: What is the name of your experiment?

{Not a section, per se, but it gets its own segment here} At the top of your page, you give your report an appropriate title. Appropriate here means that it is related to the investigation that you conducted, and the variable that you manipulated. So a title like “Brine Shrimp” is not appropriate. A title like “The Effect of Salinity on Brine Shrimp Hatching Rate” is appropriate. As always, we love a bit of humor and individuality, so if you wanted to go with something like “The Law of The Briny Deep:  Brine Shrimp Hatch Rate as a Function of Salinity”, it’s totally fine. But the bottom line is that this:

The Effect of INDEPENDENT VARIABLE on DEPENDENT VARIABLE.

Or a variation therein is somewhere in the title.

Introduction: Establishing a context for the lab

The introduction section for your report will include some/all of the following subsections as they may be required. These can be individually delineated, or cohesively integrated, as per your preference:

A. Background

In this section of the lab report, provide the reader with background information that will help them understand the experiment you have done. The introduction also informs the reader about the underlying biological concept of the lab. This section includes and defines/explains any unfamiliar terms that might be used to clarify ideas for the reader, particularly ones that you are going to use later on in your report. You are going to want to cite information from somewhere other than your own brain, and as such, include the sources you have cited here in a reference section at the end of the lab. Do not forget to include in-text citations in this section, where appropriate.

B. Objectives:  Establishing the lab’s purpose  

In this section, list what the objectives of the lab experiment are. Why did you do this lab?  What was the point? The lab, and related course material will give you plenty of context for each lab (which can be cited as per the previous section). Bullet points are fine to use here if it helps you frame your thinking.

C. Research Question and Hypothesis: Establishing a question and a prediction

In this section, you provide a testable question that addresses a problem. This problem can either be one your teacher assigns, or one you devise on your own.

• Establish what you think will happen during the lab.
• Any hypothesis is framed as a testable, predictive and explanatory statement.  
• Explicitly identify your dependent and independent variables.
• If it’s helpful, please use the “if, then…because” format for framing your hypothesis, but you don’t need to use that format if you can accomplish the same purpose using other phrasing.
• After stating your hypothesis, include a few sentences explaining why you think your hypothesis is what it is. In other words, don’t just state your hypothesis and move on, include a justification of why your hypothesis is a reasonable one based on what you know/are learning in our class.

Methods: What equipment, organisms, or reagents did you use?

The methods section for your report will include some/all of the following subsections as they may be required.  These can be individually delineated, or cohesively integrated, as per your preference:

A. Materials

A complete list of the supplies used during the experiment is provided here. Be as specific as possible. Include the volumes of tubes and cylinders. Remember to follow the style conventions described earlier in this document around organism names, genes, proteins, reagents, data, etc. Include the model and manufacturer of any complex apparatus.

B. Procedure: How was the experiment conducted?

What follows is a very detailed description of this section’s components for the purpose of this guide, but you will typically integrate the below items into something much more cohesive and holistic.

This section outlines exactly what steps were taken to conduct the experiment and is conventionally written in the third person past tense (ex. this happened, not I/we did this)  This section is concise and describes exactly what was done during the experiment. You want to make sure your procedure explains how you measured your independent and dependent variables, as well as your control treatment (if there is one) and your experimental constants. Generally speaking:

• You want to have at least 5 degrees of variance in a continuous independent variable (there will definitely be exceptions to this).
• You want to hold every variable that isn’t your independent variable constant across all trials, or account for their variance if its unavoidable.
• You need to have at least 1 control treatment for your experiment. The control is the experimental treatment that is used for a comparative purpose across all other experimental trials.

This section is written in sequential order (numbered steps are fine). If you did not design the procedure yourself, you do not need to write up this section of the lab, you can simply reference the document that you took your procedure from (citations strike again). Similarly, if you adapted your procedure from another protocol, you can say as much, cite the protocol as a reference and then delineate how you have adapted the procedure for your purposes.  

• You can provide a reference to any borrowed or adapted protocol in your reference section, along with an in-text citation in this section.
• Wherever possible and appropriate, include a diagram or photograph of how you set up the experiment. Be sure your diagram includes a title and any necessary labels. It is recommended that this diagram be annotated to illustrate how it functioned within the context of your experiment.
• If you have to decide independently how much of a substance or a solution to use, state your reasoning or show any relevant calculations.

Make sure that your procedure is detailed enough so that another person could repeat your work by reading your report. Your procedure speaks to validity measures. Validity measures are things kept constant to make sure experimental measurements are valid and consistent (ex. cleaning test tubes prior to use, cleaning the microscope lenses, using the same ruler…). Your procedure also clearly states how you collected data:

• What measuring device did you use, what data did you record, when did you collect data?
• What qualitative observations did you look for?  Explain how you set up the investigation so you had multiple trials of data collection.
• The procedure aims to allow collection of “sufficient relevant data”. The definition of “sufficient relevant data” depends on the context. The planned investigation anticipates the collection of enough data so that the problem question can be suitably addressed and an evaluation of the reliability of the data can be made. As a rule, the lower limit is a sample size of five. Very small sample sizes run from 5 to 20, small sample sizes run from 20 to 30, and big samples run from 30 upwards. This will vary within the limits of the time available for an investigation, and will in turn impact the type of analysis you can reasonably conduct on your data.

If you are combining data with data collected by other students in the class, indicate that explicitly in your procedure and explain why this pooling of data was done. If you are sampling only a portion of a population, explain how and why your particular sampling method was employed.

Your procedure must be safe and ethical. Organisms, including humans, can not be subject to harm in your investigation in any way. Include any safety precautions that were taken during the lab.

Results: What data do you have?

The results section is considered according to two separate criteria as described below.  Elements in this section will be highly context-dependent based on the particular lab, but an exhaustive description of what goes in this section is provided below for the purpose of this guide.  

Note: More than most other sections, the information in this section will likely address elements for labs that do not conclude with a formal full report (ex. Table formatting, graph presentation, etc.)

A. Data Collection: What information have you gathered?

Your data section included processed data gathered during the lab. This includes both qualitative and quantitative data (typically some elements of both are present):

• Qualitative data can include descriptions and photographs or sketches, which are in color since we are often working with living materials. Sketches accurately represent what is being depicted so that the reader does not have a question about what the sketch is supposed to represent.
• Quantitative Data Calculations are shown (my advice is to use an equation editor for nice looking calculations). Statistical analysis (mean, standard deviation, standard error, chi-square analysis, t-testing, etc. as necessary) is similarly demonstrated.

In circumstances where you would like to include unprocessed raw data, please either attach it in an appendix as a properly-formatted table or series of tables, or link to an external repository (ex. a spreadsheet).  Data does not generally appear in the results section as unprocessed raw data.

Degrees of precision:  

It is important to be aware of the precision of the measuring instruments that we use when recording data. Generally the accepted rule is that the degree of precision is ± the smallest division on the instrument. Let’s look at an example using a ruler, graduated in millimeters, to measure the length of a leaf:

• You will probably find the edges of the leaf lie close to a millimeter division but probably not right on it.
• Recording the leaf as "4.5cm-and-a-bit" long is not very useful. So the length of the leaf in this example is recorded as 4.5cm ± 0.1cm.
• The degree of precision will influence the instrument that you choose to make a measurement. For example if you used the same ruler to measure an object 0.5cm long the degree of precision (± 0.1cm) is 20% of the measurement, this is a very large error margin and, so, it is not very precise. Therefore, it’s important to choose an appropriate instrument for measuring.

B. Data Presentation: How will you represent the data you collected?

All lab reports include at least one graphical representation of your data and two data tables (processed data always go here. See note above about appending raw data as an appendix). Additionally, all calculations are shown in this data section.

• Label all graphs, drawings, and images as figures in numerical order (ex: figure 1, figure 2, etc.).
• Do the same for tables, though number them separately from figures (ex: table 1, table 2, etc.).
• Give each table, figure, etc. in this section a one-sentence caption explanation of what is being shown. For each graph or table you construct, provide a brief description of the data trend the graph or table shows. For example, if a graph clearly shows a negative correlation between two variables, give a brief statement about the trend underneath that graph. If drawings/photographs are included, make sure they are clearly labeled and accurately representative of what you are depicting.

Data table specific formatting conventions:

Present tables as organized, and informative. Use units wherever possible. Here are some items to keep in mind when constructing data tables:

• The table is easy to understand
• The table has a specific title
• The table has column headings
• The table includes the unit of measurement (always in metric units)
• The table includes the measurement uncertainty of the measurement tools used (or, if the data was a count, indicates that “counts have no measurable uncertainty”).
• Uncertainty is usually stated in a column heading or as a footnote at the bottom of the table.
• The table has a consistent and correct number of digits for each measurement
• The table has decimal points aligning down a column (if applicable) and numbers centered in the column
• The table indicates which data was collected by which student IF the data was collected and pooled across multiple students.

Graph specific formatting conventions:

Graphs can either be generated on a computer program/website of your choosing, or neatly composed by hand and adhere to all proper graphing techniques. Make sure the trend being shown in your graph is clear and not obscured by poor design choices. Information graphic design is a learning process, but here are some general items to keep in mind when deciding how to represent graphs:

• Use the correct type of graph for the type of data you are presenting.
• Graphs have appropriate scales that maximize the visualization of your data (it is frequently appropriate to begin an origin away from 0 to accomplish this particularly if you don’t have data for a zero value), labeled axes with units, and accurately plotted data points.
• If useful, add a best-fit line to show the overall trend of the data.
• If a mean is calculated, only graph the mean, not all data points. When a mean is graphed, its associated 95% confidence interval error bar (2xSEM of the sample) or other error bar are also included (and labeled/captioned as such).
• Legends (keys) are not always necessary, but use them whenever more than one trend line or data set is graphed on a common set of axes.

Drawing/Image specific formatting conventions:

Drawings and images are considered to be lab data. Unlike tables and graphical representations, not all labs require drawings/images. Here are some items to keep in mind when deciding how to represent drawings and images:

• Include labels written off straight, horizontal lines to the right of the side of the drawing. It’s ideal to have the labels form a vertical list.
• Be accurate. Draw what you see; as you see it, not what you imagine might be there.
• Include a title that states what is being shown and what magnification (if any) it was drawn under.
• Where possible, a scale and/or scale line is very useful for images drawn under magnification.

Statistics:

Statistics are useful mathematical tools which are used to analyze data. Common statistics used in biology are:

• Mean
• Range
• Median
• Percent change
• Standard deviation (to determine amount of variation around a mean)
• Standard error (to determine the amount of variation in the magnitude of error, and used to calculate 95% confidence intervals for averages of continuous data).
• T-test (to compare two means to determine if they are statistically different from each other). When a t-test is calculated, indicate the significance level at which your critical T value is determined (we typically use the 95% confidence interval, 0.05).
• Chi-square (to determine if “observed” results are significantly different from “expected” results). When a chi-square test is calculated, indicate the significance level at which your critical chi square value is determined (we typically use the 95% confidence interval, 0.05)
• Monte-Carlo simulation techniques. If possible, include a link to the spreadsheet or other simulation you used in your Monte-Carlo technique.

Calculations and Data Processing:  

Show an example calculation for each statistic you calculate. Given the nature of electronic word processing programs, it is strongly recommended that you use an equation editor to render equations and calculations (links to several equation editors are provided in the references for this document). 

• Show the units of measurements in all calculations.
• Round at the end of a calculation. Take care not to reduce or increase the reported precision of values due to calculation artifacts.
• Present your data processing results in a table.

Discussion:  What does your data mean?

The discussion section for your report typically includes the following 2 sub-sections. These can be individually delineated, or cohesively integrated, as per your preference:  

A. Conclusions: What does this all mean?

The conclusion section of the lab is where you explain and analyze your results, relate the experiment to course concepts, discuss potential limitations to the activity you did, note any errors made, and provide suggestions for improvement or future study. The following questions will help guide you in writing the conclusion section for any of our lab activities. Do not address these questions individually (or even in total), but use them to construct your narrative:

• How has your understanding of the concept improved or otherwise changed from doing the lab?
• If you used a statistical hypothesis, be sure your conclusion is congruent with the results of that test.
• Did your data support your hypothesis or was it refuted? If not, why do you think your data did not support your hypothesis?  Explain how you came to this conclusion.
• How might what you have learned in the lab be applicable in the future?
• How might what you have learned in the lab be connected to the larger understandings of the course?
• Did the lab work the way that you thought it did, or were there any unexpected results?  If so, why do you think this is?  If not, why do you think it didn’t?

• What are some of the limitations of your experiment?  How could these limitations be addressed?
• What are some of the limitations of your conclusion?  Can the results be generalized to other situations/conditions?  How might your results explain a process in the “real world”

Additionally, you may find useful items for discussion in the materials that you are provided with when conducting a particular lab. If possible, cite literature related to your conclusion. Does your result coincide with published results? Does it refute published results?

B. Experimental Evaluation:

In this section, you evaluate your procedure, how you thought it would work compared to how it actually worked, how you could improve/refine the procedure and generally what you could do in the future to have a better lab experience. This section also includes a discussion of sources of error in your lab. The following questions will help guide you in writing the experimental evaluation for any of our lab activities. Do not address these questions individually (or even in total), but use them to construct your narrative:

• In general, how much confidence do you have in your results? If you did a hypothesis test, make sure to state your answer in terms of the percentage that the hypothesis test determined.
• Why do you feel confident (or not confident) in your results?  
• What did you do to ensure validity?
• Looking back on the lab, is there anything that you, your group, or the class could have done differently?  Be detailed in your recommendations.
• Discuss the sources of error in the lab, why/how they contributed to errors, and what could be done (if anything) to address those sources of error.What follows are some of the more common sources of error seen in labs, though if you speak to them in this section, explain how they showed up within the specific context of your experiment:

• Human error: Human error can occur when tools or instruments are used or read incorrectly. Human errors can be systematic because the experimenter does not know how to use the apparatus properly or they can be random because the power of concentration of the experimenter is fading. Automated measuring using a data- logger system can help reduce the likelihood of this error; alternatively you can take a break from measuring from time to time.
• Calibration error: Some instruments need calibrating before you use them. If this is done incorrectly it can increase the risk of systematic error.
• Random errors: In biological investigations, the changes in the material used or the conditions in which they are carried out can cause a lot of errors. Biological material is notably variable.
• The act of measuring: Could the measurement uncertainty have affected the results? Why or why not?
• Uncontrolled variables: What variables were not controlled? What effect might each of these uncontrolled variables have had on your data? On the conclusion?

• How could the lab be changed or modified to provide more accurate data or to measure other aspects than what was measured?  What improvements could be made?  How could the weaknesses identified be improved?
• What are some of the areas of future or expanded investigation that might be worth looking at?  

Additionally, you may find useful items for discussion in the materials that you are provided with when conducting a particular lab. Endeavor to be as complete and specific as you can be in this section.

References:

All lab reports adhere to stylistic conventions of either the APA or IEEE (preferred) editorial style. If you are unclear about how these stylistic conventions apply (both in terms of a reference list, AND in-text citations), I encourage you to consult the references provided below. Wikipedia is never be used as the sole source for any aspect of a lab report, though it can certainly be used as one of a collection of supporting references (as long as you are diligent in evaluating the accuracy of the particular article).

Artificial Intelligence (AI) Declaration:

In keeping with course policies around the use of Artificial Intelligence (AI) by students in this course, any lab report that was developed with the use of any AI program needs an AI Declaration Section. The section includes all of the following information:

• The AI platform(s) used, and the methods by/purpose for which they were used.
• Where possible, also include any specific prompts, or exemplary prompts (if you have a lot of them).

Appendices:

If you choose to include appendices (for raw data, perhaps), put them after the reference section/AI Declaration and be presented in letter order (ex:  Appendix A, Appendix B, etc) with single-sentence descriptive titles.  Friendly reminder that if you are including raw data, you can link to a public repository of the data (ex. an online spreadsheet) which is likely more elegant a presentation than appending to the report.

Length Considerations:

There is no such thing as “correct length” for a lab report. At the same time, it might be suggested that since these documents are the result of weeks of effort, and given what is required in them, there are certain benchmarks that may sound an alarm if they are not close to being met for particular sections. That noted, please do not ever add material to a section for the sake of making it longer.  If you use the guidelines in this document as completely as you can, you do not need to worry about issues of length.

Collaboration Considerations:

When a group effort is submitted, evaluation and feedback provided applies to all group members.

The following specifically applies to independently written lab reports: The following aspects of a lab report are allowed to be similar/identical among members of the same group:

• Raw data (values/photos/etc.)
• Tables, Graphs & Diagrams
• Calculations
• Sources used.

All other work needs to be independently generated. While groups are encouraged to work together to get feedback and share ideas, the work that is submitted needs to be original enough to not be demonstrated to be identical when subjected to computational similarity analysis or other tools (ex. Version history). Plagiarism considerations congruent with SAS academic honesty policies are likewise applicable.

Exceptions/Alterations

This document is intended as a guide, not as a “no exceptions” use case. The particular details of any one lab report may change from what is described above, in some cases significantly so. In all instances, the specific details and requirements for any lab report will be discussed with the class. Any details/alterations to a specific lab report (as conveyed in the supporting materials and class discussions related to that specific lab experience) take precedence over the guidelines explained in this document.

Additional Support:

The following resources may be helpful for particular aspects of your lab report writing:

Writing Process

LabWrite Lab Report Help:

•  http://labwrite.ncsu.edu

Wikipedia IMRAD format Page:

• http://en.wikipedia.org/wiki/IMRAD

Technical Help

Google Docs Help Pages:  

• http://support.google.com/docs/

Graphing-

• Making Graphs (aka “Charts”) in Google Docs Spreadsheets        
• Plot.ly:  Robust Online Graphing Tool (my preferred online graphing tool):

Using the Google Chart API directly (no spreadsheet required- 2 different sites):  

• http://acme.com/chartmaker/
• http://almaer.com/chartmaker/

Create-A-Graph Graph Construction Website:  

• http://nces.ed.gov/nceskids/createagraph/

Equations-  

Editing equations on a computer can be a bit tricky to learn. As you probably know, trying to format an equation in a document is almost impossible (at least if you want it to look good). On computers, all equations are basically handled by a markup language called LaTeX, which is really powerful, but also a bit tricky to learn. Fortunately, there are a variety of visual editors that you can use to help you make your equations, but you are going to make a few mistakes before you “get” the logic that works under these systems. Google Docs has an in-program editor (available in the view menu) which is based on LaTeX, but is a bit simplified.

• Using the Google Docs Equation Editor 

There are some nice visual equation editors that use full LaTeX scripting (you would export these equations as .png files and then import them into your lab report). Here are two that are pretty easy to use:

• http://www.codecogs.com/latex/eqneditor.php
• http://www.sciweavers.org/free-online-latex-equation-editor

Citation/Reference Styles:

Note: MLA Style is not an acceptable citation/reference format in AP Biology.

APA Style Guide:

APA Style is widely utilized in science writing, and as such it is agreeable for AP Biology

• https://apastyle.apa.org/style-grammar-guidelines        

IEEE Style Guide:

IEEE is secretly a much better style guide and convention, so it is also agreeable for use in AP Biology.

• http://libguides.murdoch.edu.au/IEEE

Citation Machine Reference Formatter

(does not do IEEE style citations):

• http://www.citationmachine.net

Generalized Report Grading Criteria:

Provided below for your reference are the criteria that are generally considered when grading a lab report. Not all criteria are given equal consideration when scoring a lab.