The Writing Place

The goal of the introduction is to give background information and establish the purpose of an experiment. In establishing the purpose of the lab, you should also tell your reader why this experiment bears importance in the real world. The introduction should briefly summarize what you did in the lab and why your work has practical applicability.

In this section, you will discuss how you conducted an experiment step by step. Here, you might use charts or graphs to explain information. You should go through the process of the experiment and explain what you did and provide a rationale for why you did those steps. It is helpful to use transition words such as “next” and “then” so the reader can distinguish the different steps. The methods section should give the specifics of the experimental process so that someone else could replicate it in the future.

The results section is where you discuss the scientific outcome of your experiment. This may be another place where charts and graphs are helpful to display information. This section should focus on what you observed, rather than the interpretation of the results.

The discussion section is where you interpret the data you gathered and wrote about in the results section. In this part of the report, you should relate back to the purpose of the experiment and discuss how the methods and results reflect the goals of the lab. In this section you can also explore ideas for other experiments based on the results of this lab. Finally, you should end by summarizing what you did in the experiment and what the experiment accomplished.

• Be concise. If a chart or graph can state your results or methods better than you can in words, it may be more helpful to a reader.
• Headings can be an easy way for your audience to identify different portions of your report.
• Show that you understand what different terms and definitions mean. For example, if you use the word “leucine,” be sure to indicate that you know what leucine is and why it was important in your lab.
• If you include charts and graphs or other figures, be sure to label axes. Clearly caption the figure so the audience understands the relevance of the information.

One of the keys to a good lab report is organization. Try to identify in which section of a lab report the following sentences belong:

1. After we collected samples of bacteria from the lake, we inserted them into a Petri dish for three days so the cultures could grow.

2. The cornus swida grew four inches over the course of a month.

3. In this experiment, we injected infected chimpanzees with an Ebola vaccine to test survival rate. Because chimpanzees share much DNA with humans, this vaccine could bring scientists another step closer to curing Ebola.

4. Because the olive oil could not power the car, we have concluded that the substance is not an effective replacement for gasoline.

5. Because sugar dissolves in water, we could not use sugar as a substrate in our terrarium and used limestone instead.

Answer Key

1. Materials and methods. This sentence describes the procedures you used in the experiment and explains why those procedures are important.

2. Results. This sentence describes what happened in the experiment, but does not explain the implications of the cornus swida‘s growth.

3. Introduction. This sentence summarizes the overall goal of your experiment and gives its real world applicability.

4. Discussion. This sentence explains why the results are important and applicable to issues in the real world.

5. Materials and methods. This sentence not only tells the reader what materials you used in the lab, it also gives a rationale for the use of those materials.