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LAB REPORTS

BIO 361 LAB

The outline to follow for the lab reports simulates the format commonly used for research reports in physiological journals. It consists of four parts: Introduction, Methods, Results, and Discussion, which are each described below.

The deadline for all reports is 2 weeks following the Laboratory meeting for the exercise that you are writing up. Five to six pages of text should be an adequate length.

Introduction: This is a brief explanation of why the observations you made are of physiological significance. That is, what physiological principles are involved in the exercise? What do you hope to demonstrate?

Most scientists are not prone to pursuing research without a reason. One stimulus for doing an experiment is that the scientist wishes to answer a question or resolve a controversy. Whatever the reason, the scientist must communicate the purpose of his/her research prior to explaining the details of the experiment.

In an undergraduate physiology class, you may be hard-pressed to find a reason for doing the particular lab exercise you have chosen. However, it is not legitimate to say "the purpose of this experiment was to attempt to get an "A." Rather, you should recognize that the lab exercises you are performing were originally done in a research setting and many are classical experiments that have led to significant advanced in our understanding of physiology. Therefore, your introduction should reflect an appreciation of the particular systems to be studied, keeping in mind that some ingenious individual at some time in the past designed and executed the experiment you are doing without referring to a lab manual.

Methods: Describe these very briefly. There is no need to duplicate the instructions in the lab manual, but cite the lab manual and state any deviations from the printed procedure. These would include modifications suggested by your instructor or modifications you initiated. Also note any methodological omissions and justify them. This part of the write-up should also include a description of animal or human subjects.

Results: In this section, the reader is given a description of the data and observations that resulted from the experimental procedures. This section of the paper is not the place to interpret results. It is also not sufficient to include tables of data, graphs, figures, etc., without some written explanation. Therefore, this section should ideally consist of a brief written description of observations and results with references made to figures, graphs and data tables. Always number your figures and tables in the order that they are described in your text. Do not hesitate to cut up penwriter records of experimental results to mount as illustrations. Such records should include the time scale and sensitivity of the physiological response pictured. Be sure each table, graph, or figure is clearly labeled (for example, Figure 1 - Oscilloscope Tracings of Frog Compound Action Potential).

Remember, the results section is the portion of the paper in which data are reported and summarized in a clear, concise manner. Some forms of data reduction are easier to interpret than others. You may want to display your data in graphic form rather than report raw values, especially if you are trying to emphasize a trend or pattern. Necessary calculations and formulas should be shown. If you have repeated measures for some parts of an experiment or a large number of subjects, use "means," "standard deviations" or "standard errors," and ranges to reduce the data into an interpretable form. This will make comparisons and contrasts with known values much easier to explain.

Discussion: This section is the real "meat" of the paper. In it, a detailed interpretation of data is integrated with known physiological concepts, and comparisons are made between your results and expected results. This portion of the paper gives you the opportunity to display your intelligence, creativity, powers of synthesis, and your ability to work with concepts you have learned. Here is your opportunity to relate the laboratory work to the physiological principles dealt with in the lecture and/or the textbook.

It is critical that you cite authors or footnote any information that you have derived from physiology texts. If you fail to give credit where credit is due, you are violating ethics and standards for written communication. Also, in your footnotes or references, please state page numbers of texts and articles to which you have referred for information included in your discussion.

Speculations on possible consequences of your results, on other experiments which might clarify a point, or on other techniques which may have given more definitive results are highly encouraged. These should be presented in addition to the discussion of conventional concepts. Remember that the teacher is looking for clear thinking and understanding of the experiment performed.

In summary, your discussion should show how you fulfilled the purpose of the experiment as stated in the introduction. This will hopefully provide a central theme and some semblance of unity to the report.

Assistance: Feel free to discuss with me the various aspects of this lab report. I will be glad to examine a preliminary draft of your write-up, providing helpful comments, before you write your final draft. This requires that you get an early start on your write-up and not wait until the day before it is due. Even if you understand how to write a lab report, having me evaluate your rough draft is virtually guaranteed to improve your final draft (and your score).

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Last revised on May 08, 2007

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