How to Write the Results Section of a Lab Report

Steps for Writing Your Results Section

1. Identify the variables in your experiment. This is perhaps the most important part of your paper. You will want to list all of the variables and declare which of them you were manipulating and which ones were controlled throughout your experiment.

2. Identify what happened when these variables were manipulated by explaining how they affect your dependent variable (the thing that you measure in the experiment).

3. List the conditions that were tested under each experimental variable in your results section. If you are using data from more than one condition, make sure to label each set of results in addition to describing the methods used to carry out this experiment in brief sentences.

4. Compile all of your results in a table or chart. If you have trouble understanding what you did, feel free to step back and think of another way to display this information.

5. Describe your results in words, showing how they relate to the problem stated in the introduction of the paper.

Here is an example of a Results Section:

Results Section

The first part of the experiment tested what temperature was needed to allow the maximum amount of light to pass through a plant leaf.

The dependent variable in this experiment is transmittance, which was measured using an instrument called a spectrometer.

The independent variables were temperature and wavelength of light that were used, both controlled by placing them into one of three different heat lamps.

After various trials, it was found that the maximum transmittance of red light occurred at a temperature between 40 and 50 degrees Celsius, as shown in Figure 1 below.

This is because, at approximately 40 degrees Celsius, there is a visible change in pigment colors within the leaf visible to the naked eye. The peak visible wavelength for this change in pigment color is approximately 663 nanometers, corresponding to red light.

Fig 1: Transmittance of Red Light over Time at Various Temperatures (Just an Example)

The second part of the experiment tested what wavelength caused the maximum transmittance through a plant leaf and how this relates to photosynthesis.

The dependent variable for this part of the experiment was transmittance, as in the first part.

The independent variables were wavelength and temperature, controlled by placing them into three different heat lamps.

After each trial, transmittance measurements were taken using a spectrometer for various wavelengths of light and temperatures.

As expected from the first part of the experiment, transmittance peaked at a wavelength corresponding to red light for this particular set of conditions.

However, it was found that there was a secondary peak in transmittance at 600 nanometers for this temperature and wavelength combination, shown in Figure 2 below.

Fig 2: Transmittance of Various Wavelengths over Time at a Particular Temperature (Just an example)

The third part of the experiment tested what wavelength caused maximum transmittance and how this relates to cellular respiration.

The dependent variable in this experiment was transmittance, as it has been in the previous two parts.

The independent variables were wavelength and gas mixture, both controlled by placing them into one of three different gas containers.

After each trial, transmittance measurements were taken using a spectrometer for various wavelengths and gas mixtures.

As expected from the first two parts of the experiment, it was found that red light had the maximum transmittance at the tested temperature and wavelength combination.

However, red light no longer had the highest transmittance when oxygen was removed from the gas mixture and replaced with carbon dioxide.

In fact, when there was no oxygen in the environment, wavelengths between 575 and 630 showed a higher maximum in transmittance than red light. This is shown in Figure 3 below.

Fig 3: Transmittance of Various Wavelengths over Time in Different Gas Mixtures (just an example)

This experiment showed that the maximum transmittance through a plant leaf does not change significantly when tested at different gas compositions. Moreover, although photosynthesis is related to carbon dioxide intake and cellular respiration is related to oxygen intake, their effects on transmittance can be separated.

General Guidelines for Writing the Results Section of a Lab Report:

When writing the results section of lab reports, there are some general guidelines that should be followed.

Use formal language – writing a lab report is different from an essay because it should follow the same language, format, and structure as a scientific paper. This means that all results in the results section should be written in complete sentences.

Number each section – each part of the lab report should be numbered in the order presented. This makes it clear for readers and graders to follow.

Write out all measurements – unlike most other sections in a lab report where units can be dropped, all measurements in the results section need to include units. This helps to ensure that results are reliable and accurate.

Edit and proofread – A common mistake is writing measurements in the text without including units. This makes results seem imprecise and can damage reader confidence. Check for errors like this as well as any other mistakes, before handing in the final version to your instructor.

Tips for Writing a Solid Results Section in a Lab Report

1. Make sure you have tables and figures for every piece of data reported in the paper. The reader should not have to flip through the report and read each result individually.

2. Always include units in your data and do not abbreviate anything. You should not be writing “g” or “ml” when you would normally write “grams” or “millilitres.” Instead, use gram for grams and millilitre for millilitres.

3. When analyzing your data, make sure to include any relevant graphs from previous parts of the lab report as well as those that you created in this section. Draw a line under the graph and provide a caption for it. If you are using other pieces of information from your paper, be sure to reference them.

4. Make sure to reference all outside sources that you relied upon. While this is not a literature review, the reader should know where your information came from and how it applies to what you are discussing.