So, instead of writing, “I used plastic pipettes to fill the beakers with 25 mL of water,” write “The beakers were filled with 25 mL of water using plastic pipettes. ” Use as few pronouns as possible when writing your lab report. Pronouns to avoid using include “I,” “we,” and “they. ”
For instance, instead of saying, “The results prove the hypothesis is correct,” say, “The results of the experiment proved the hypothesis was correct. " The Introduction is one of the few parts of the lab report which can be written in the present tense.
Add/subtract/merge certain structural elements of a report. Grade one part of a report more heavily than another. Require reports to be typed, using a specific font and size. Require reports to be handwritten in a research notebook.
For example, your Introduction could begin, “In this laboratory experiment, the ability of a lab microscope to differentiate between different species of single-cell organisms was tested. ” Methods and Results should all be written in the past tense, since you’ll be summarizing actions that you’ve already performed as part of the lab.
In the Purpose section you should also include background information about the experiment, including the reason that you’re performing the experiment. This information can be found in the lab manual or related microbiology textbook. For example, begin your Purpose statement by writing something like, “In this lab experiment, 3 different types of bacteria were separated using a nutrient agar plate. ”
For example, write: “The initial hypothesis suggested that the bacteria in group 1 would outnumber bacteria in groups 2 and 3 by a rate of 5:1. ” Finally, the Purpose section should state, but not extrapolate on, all techniques or tests used in the experiment. Keep things cursory here, though, since you’ll give detailed information about the techniques and methods used in the Methods section.
The type of agar (if agar was used). The type of microorganism used (if the organism types were known beforehand). The size of all test tubes, beakers, calipers, and any other type of science equipment. For example, the materials description could include a sentence like: “Five 50-mL beakers were used to contain the water and single-celled organisms. The water was applied to microscope slides using 1-mL plastic pipettes. ”
If your instructor deviated from the original experiment, make adjustments as needed. For example, write something like, “After a plastic pipette was used to place the single-celled organisms on the center of microscope slides, a slide cover was placed over each water sample. Organisms were then identified through the microscope using 50x and 100x magnification. ”
However, do not interpret the scientific data in the Results section. Only interpret data in the Discussion section. For example, write something like, “When the microscope was set to 100x magnification, single-celled organisms that were at least 0. 25 mm smaller or larger than the surrounding organisms could be identified. ”
For example, if a bacteria that you were asked to observe had consistent physical traits, describe these in the Results section. Write something like, “The reactions of single-celled organisms to different water temperatures and chemical additives were noted. It was noted that, as less-diluted chemicals were added, the organisms acted in increasingly unpredictable ways. ”
Figures and tables should also be mentioned and explained in the main text of your Results section.
The Discussion section is usually the most important section of the lab report. It shows that you’ve understood the experiment you just performed and are able to engage with the scientific implications. For example, write, “The amoebas were observed displaying consistent behavior throughout the observation period. The data suggests that the organisms were unable to detect the variety of chemicals that were added to different water samples, which the amoebas were then suspended in. ”
You could state something as simple as, “The results disproved the initial hypothesis, which failed to account for the similar sizes and colors of many of the single-celled organisms that were identified. ” If your results do not support your hypothesis, ask questions like, was there any error during the experiment? Did you miss a step in the experiment? Did you use proper techniques? Were your results accurate?
If you should include a References section instead of a Bibliography, you’ll only need to include citation information for sources that were cited in the lab report. Ask your instructor which citation style you should use when compiling your Bibliography. For example, most microbiology TAs will ask you to use Chicago style. Most lab reports have short Bibliographies, since very few lab reports cite more than 1 or 2 sources (if any).
