Dr. Dulai's Bio 184 section Lab 1.1 notes

Updated: 7 September, 2006

Information on group presentations added

Lab Report Format

I am presenting a multitude formats. Utilize any one and stick with it.

FORMAT 1

TITLE
Always have a short and meaningful title to accompany the report.

INTRODUCTION
This section is as short as a few paragraphs or as long as a few pages. It serves to introduce your experiment. Start with general statements and become more specific.

The first part of the introduction should set the context for your experiment by briefly providing background information. You should present what information is known from previous studies, and then state what additional information your experiment may provide. Be sure to give proper citations when you state facts or ideas from outside sources.

EXAMPLE: The larch is an evergreen that loses its leaves in the fall (Jones, 1921).

In the second part of the introduction you should describe the specific questions you chose to study. State what you did in a general way, eg., "We investigated the effect of obesity on heart rate by comparing heart rates of fat an thin people after they climbed stairs", but do not give away the specific details of your Methods or Results. Specifically state your hypothesis at the end of the Introduction. However, not all scientific studies, have a hypothesis; the scientist just wants to obtain more information . You need to decide whether a hypothesis is appropriate for your study. Return to page 1.

METHODS
The experiment has been completed by the time you write your report, so use past tense. This section includes a brief outline of the methods used in the experiments For any details that are contained in other literature (eg. your lab manual), you may refer the reader to the methods described there by using a proper citation; you do not need to reiterate these details in your report. However, if the laboratory procedures were changed, describe these in this section.

The purpose of this section is to allow other experimenters to duplicate the methods you used, so it should be detailed enough so that someone else could read your report and repeat the experiment. However, you should NOT include trivial details such as "we used test tubes that were 10cm long," or "the test fish were kept in a beaker before the experiment began."

It is important to quantify your treatments whenever possible; for example, how many milligrams of caffeine did each person injest, or how long did you wait between administering salt and measuring blood pressure?

Good Example:

Cells wre exposed to 0, 15, 30, or 45 seconds of ultraviolet irradiation. Cells from each irradiation treatment were diluted to 10-3 and 10-5 of their original concentration. One ml of each of these dilutions was plated on nutrient agar and incubated overnight. The number of colonies was counted the next day.

Bad Example:

Our lab bench received cells from treatment #1, and these were serially diluted, so that there were 2 different concentrations of bacteria to count on the petri dishes. Lab bench 2 received cells from treatment 2. These were also serially diluted, resulting in 2 different concentrations of bacteria to count.

Problems with the bad example, which contains nearly the same number of words but much less information:

* Trivial information is included (Our lab benched received...)
* "Treatment #1" is a poorly identified variable. The reader will probably have to refer back to a previous page to find out what this treatment is.
* Important details are left out, such as the number of seconds the cells were irradiated, the dilution factors, and the temperature at which the cells were grown.

RESULTS
The results section always starts with normal paragraph (text ) format, NOT with tables or figures. You MUST first direct the reader's attention to EACH table and figure before they appear, indicate what they show, and summarize the important data in each.

Good Example of How to Begin the Results:

Results
The mean IQ of Stanford biology students was found to be higher than the mean IQ of other Ivy League students and of students from many colleges, as seen in Figure 1.

As with all writing the results should be organized into coherent logically organized paragraphs and sentences. .

Data is reported in 3 ways:

* Text or paragraph form, if there are just a few numbers to report.
* Figure: a graph, picture, or diagram
***** A figure will have a detailed legend at the bottom ******
* Table: something that contains only numbers, and has a detailed legend at the top.

See examples of figures in, "The effects of jumpamine....."
Report ALL data, even if it was unexpected or if it did not support your hypothesis. Include data for any pilot experiments. Types of data will include:

* General observations made during the experiments
* Quantitative results (summarized as means, standard deviations etc.), which normally appear in figures and/or tables
* The results of statistical analyses. This can be done in the text if it is simple. If there are many numbers, put the data in a table.

Reporting of statistical analyses:

Statistical analyses are frequently done poorly in lab reports. In the text, go straight to the important point(s).

* Good Example:
The mean weight of plants grown under white light was greater than the mean weight of plants grown under green or red light as seen in Fig. 1. The difference between means was significant (p = 0.052), as seen in Table 1.

* Bad Example:
The mean weight of plants grown in Treatment 1 was 27grams. The mean weight of plants grown in Treatment 2 was 19 grams. The variance was 99.1343. The T value was 3.1384. The df was calculated to be 12. The p was 0.04, so the probability that the results were to to chance was less than 5%. All the data and t-tests can be seen in Figure 1 and Table 1.

Problems with the bad example:

o MUCH too detailed and wordy; for most of this information, the reader can be directed to the figure and table.
o Great precision is implied by the number 3.1384; round off to 3.14 or even 3.1
o The reader probably has forgotton what "treatment 1" and "treatment 2" are; use meaningful labels that the reader does not have translate by referring to previous pages.
o You do not need to define what "p" means, and it is redundant to do so (it is defined as the probability that the results are due to chance); readers of scientific literature are familiar with the term.

Do NOT discuss the implications of the results in this section, nor attempt to explain why various results occurred.

Most of the DETAILS of the results will occur only in figures or tables. Only the important points of each figure and table should be described paragraph format; don't reiterate the whole figure.

RAW DATA is NOT normally reported in the Results. Readers are usually interested only in SUMMARIZED DATA, such as means, standard deviations, totals, etc. However, since this is not really going to be submitted for publication, you should include any raw data and lengthy calculations in an APPENDIX so your instructor can detect any errors you may have made.

DISCUSSION
This is usually the most important part of your paper. This is your chance to be original, cleverly interpret the results you obtained and draw general conclusions from them. Information in the discussion should go from the specific to the general. This is a typical order of topics which might occur in the Discussion:

major conclusions (don't list this as a subheading)

Begin the discussion by briefly stating the major conclusions from the results. Explain what the results mean. Discuss whether the results SUPPORT or do NOT support your original hypothesis(es). Your experiment is really very limited in scope, so DO NOT claim that you have "proven" or "disproven" a hypothesis; you perhaps obtained some small bit of evidence to support a hypothesis, or you provided some evidence which contradicts a hypothesis.

expand on your results

In next paragraph(s) expand your discussion of these results. You might wish to compare them to results from other studies, which you should cite properly.

introduce some new ideas

As the discussion continues it is important to offer some original ideas and interpretations. For example, discuss the implications or your results for the biology of the organism(s). For example, why did the behaviors you observe evolve? You may wish to suggest new experiments which would shed further light on the questions raised by your results.

improvements in experimental design

Your best guess is that the results reflect reality. Students often feel that their discussion should consist mainly of an analysis of all the things that went wrong with the experiment. We strongly discourage this approach. Naturally all experiments have some weaknesses, but for the purposes of this exercise assume that your results are reasonable. It is OK to get negative results (no significant differences). You may, however, suggest additional experiments using different methods that may improve our understanding of the topic.

REFERENCES
In this section you will list any literature which you have cited in the text. List ONLY those references which you have specifically cited. References are listed in alphabetical order, by the first letter of the first author's last name .

See correct format in the sample paper, "The effects of Jumpamine Chloride...."

FREQUENT PROBLEMS IN SCIENTIFIC WRITING

The following are a few hints to better scientific writing. Read them carefully.
o Underline or italicize scientific names. The genus should be capitalized and the species name lower case (unless it's a proper name). The word "species" is both singular and plural; there is no word specie'. The plural for "genus" is "genera"

o Be concise by eliminating unnecessary words. Some examples:

In his paper on spiders, Jones stated that spiders can't fly (Jones, 1950).
In order to conduct the experiment we used 10 test fish.

The bold faced words in the above examples can all be eliminated.

o Use the standard scientific citation format:

Smith (1987) found...
Eagles eat turtles (Smith, 1987) ...
o The cited articles should be listed in alphabetical order at the end of the paper under "Literature Cited."

o In general, DON'T use quotes.
Instead, paraphrase the author and cite him/her. Quotes interrupt the flow of your text. Only quote if the precise wording is absolutely critical. If you must quote, incorporate 2-3 lines into the text. Longer quotes should be isolated by single spacing and wider margins.
o If an entire paragraph comes from a certain author, cite once at the end of that paragraph, not after every thought or sentence.

o Scientific writing is formal communication. Don't use conversational language, colloquialisms or slang.

o Read your paper out loud, or, better, have a friend read it to you. This helps with the placement of commas (at pauses) and points out awkward phrases or sentences.

Some frequently misused/misspelled words:
o affect/effect
The effect of their misuse will be that your grade will be affected by subtracting five points.
"Effect" is a noun (usually).
"Affect" is always a verb.
o its/it's
"It's" is the conjunction "it is".
"Its" is the possessive, and possessive pronouns don't have apostrophes. e. g. hers/his/ theirs.
o their/there
I assume this is just carelessness, but it happens too often.
o between/among
Between refers to two things, while among refers to more than two.
o fewer/less
Use "fewer" if you can count the items, "less" if you can't. e.g. less water, but fewer boats.
o amount/number
Use 'amount" if you can't count them, "number" if you can. e.g. The amount of sand and the number of rocks
o oftentimes
Drop the "times"; it's redundant.
o different from / different than
Different from is correct; different than is not.
o than/then -- each of these is sometimes used when the student means to use the other; proofread!
o dependent
This is commonly mispelled (there is no a in this word).
o prove/disprove
These words should almost never be used in a biology lab report. Your experiment is very limited in scope and will only provide evidence for or against a hypothesis.
o Use parallel constructions in a series. e.g. The dog likes to run, play and bark. NOT The dog likes to run, play, and he barks too.
o Always put a zero in front of a naked decimal point (0.12, not .12).
o Species is both plural and singular

FORMAT 2

Labs are an extremely important and helpful part of the course in that they require you to think in depth and detail about its material on a regular basis. While each lab may differ slightly in its mechanics, below are outlined some general recommendations for completing each lab and its associated lab report which will facilitate the exercise for both you and the people evaluating your lab reports.

BEFORE LAB:

Read through the instructions for the lab exercise.

Ask yourself:

* What are the goals of the lab exercise?
* What data will be examined? How will an examination of this data help to achieve the goals of the lab exercise?
* If there are several data sets, are there any physical relationships we know that relate the variables?
* If the lecture course has already covered the material, then try to utilize that knowledge and place that into context with the lab?

IN LAB:

Work through the exercise. Consider the answers to any questions asked in the exercise as notes for the scientific essay you will hand in. Record all variations from the expected.

As you work through the exercise, you should constantly be asking yourself:

* What are the relationships you observe in the data?
* Do you know of any underlying physical principles which might produce the relationships you observe?
* Is there a common theme to the relationships you observe in the data? Are these relationships relevant to the goals of the lab?

LAB REPORT FORMAT:

After each lab you will write a lab report carefully constructed to express your major observations and findings. The length of the report will vary depending on the lab, but should not be fewer than 2 pages nor more than 6 pages, excluding graphs. Keep in mind the comprehensive and detailed format you may have encountered in lab reports for other science courses: could someone duplicate your experiments upon reading your report? The brevity of your report requires that you attempt a concise writing style, touching only upon your most important observations and results. Nevertheless, you must also present as much supporting detail as is necessary to support your conclusions and allow the reader to understand the logic by which you obtained them.

Think of the report as a scientific essay. It will have a title and sections containing:

* Introduction
* Procedure (Methods & Materials)
* Results
* Discussion
* Conclusion

A brief description of what should be included in each of these sections is included below.

* Title.
o The title should summarize, as specifically as possible, the subject of the lab.

* Introduction.
o Your introductory paragraphs must include:
o Purpose: A single, concise statement of the major objective of the lab, i.e. what are the questions you are tying to answer.
o Background: A brief summary of the topic being investigated, including any information which may be necessary in order to understand your stated purpose of the lab.
o State the major results/findings of the lab exercise.

* Procedure (Methods & Materials).
o Include the information necessary to allow someone to repeat what you did.
o What data did you use? Include metadata (data about data) such as the data source (i.e., satellite? surface observations? modeled?) and the temporal and spatial resolution of the data.
o Include geographic locations, definitions of key terms, and anything else necessary in order to understand exactly what you did.
o Include ALL variations from the methodology used.

* Observations and Results.
o What did you observe in each part? Include all observations made at the suggestion of the lab exercises. Always include the units of physical quantities and label axes of plots.
o Describe any relationships that you observed between variables.
o Where appropriate include figures, graphs and calculations.

* Discussion.
o This is the most important part of the lab, as it is where you interpret your observations and results.
o Give explanations for and implications of any relationships observed. Were the relationships as you expected from underlying physical principles?
o Support your ideas with specific, quantitative references to the results of your analyses. How do your observations lead to the conclusions you reached?
o What are the main sources of uncertainty in interpreting your observations?
o Address any interesting questions you may have had as you were working through the lab exercises, as well any general questions included in the lab exercises.
o Can you make any generalizations? Why or why not?

* Conclusion.
o Summarize your results, the main points of your discussion, and how they relate to your stated purpose of the lab. It is a good idea to include how the main points of your discussion are connected, in order to demonstrate the overall significance of your findings and the concepts you learned.

AFTER WRITING YOUR ESSAY:

* Make sure your writing is clear. If you read it aloud to yourself or a friend, does it make sense? Don't forget to use the spell-checker in your word processor.
* Check to be sure you addressed all the questions included in the lab exercise.
* Check to be sure all pertinent plots, graphs, etc. are included and staple all pages of the lab report together.

For perfectionists:

Lab Report Check List

___ Title describes the experiment and results

___ Abstract (optional, but if you have one, it must be labeled "Abstract")
___ less than 50 words long

___ Introduction section
___ Background information
___ Importance of experiment
___ Preliminary observations (if applicable)
___ Hypothesis or question
___ Less than 1 page long

___ Methods section (must be labeled)
___ Describes or refers to every lab procedure & analysis procedure used
___ Cites a description of every lab procedure & analysis procedure used (if possible )
___ NO lists
___ NO description of data

___ Results section (must be labeled)
___ Includes written (text) description (summary) of your results that can stand alone (without tables & figures)
___ Tables and figures have titles (format: "Table 1: Title" or "Figure 3: Title")
___ Tables & figures can stand alone (captions or titles must describe them well enough to be taken out of context)
___ Units (e.g., "mm", "seconds", etc.) given for all measurements, tables, figures, etc.
___ Statistical analysis of data included
___ Text refers to each table and figure
___ NO titles start with "Graph..."
___ Some tables and/or figures are present
___ NO raw data included
___ Summary statistics included
___ NO interpretation
___ NO description of methods used

___ Discussion section (must be labeled)
___ Answers questions set out in introduction (or states whether you reject the hypothesis)
___ Interprets& explains data
___ Discusses errors & problems that arose
___ Discusses how errors & problems could be solved
___ Discusses the next step or future work for this project

___ LIterature Cited section (must be labeled)
___ Alphabetical by author
___ Gives author's name for each citation
___ Gives publication date of each citation
___ Gives title of each citation
___ Gives location of lectures
___ Gives publisher of books
___ Titles NOT underlined, in italics or "quotation marks"
___ Gives journal name (in italics) for journal articles
___ Gives vol. and page numbers for journal articles
___ Gives URL of web pages
___ Gives access date for web pages

___ Information in lab report is not copied from another document

___ Lab report format is correct
___ 12-point font (standard font such as Times, New York, Arial, or Helvetica)
___ Page numbers in the upper right-hand corner (except on the first page)
___ Your name on one page (front of first page or back of last page)
___ Internal citations are present
___ Quotation format is correct
___ Quotations are short
___ NO page number on the first page
___ Information in lab report is accurate
___ Less than 5 pages of writing
___ 1.5 inch margins
___ Double spaced

___ Proofread lab report
___ Looked up infrequently used words (make sure you know the definition of EVERY word you use)
___ Used first person
___ Subjects and verbs agree
___ NO title page or cover page
___ NO passive voice
___ NO vague language
___ NO subjective language
___ NO misspelled words
___ NO incomplete sentences
___ NO dangling modifiers
___ NO run-on sentences
___ NO imperatives (not written as instructions)
___ Used past tense (not future or present)
___ Genus & species names are italicized
___ Only first words & proper nouns capitalized

___ Friend or instructor has proofread lab report

FORMAT 3

Click here to see the format

FORMAT 4

Click here to see the format

FORMAT 5

by Jennie Skerl

Overview
Although engineering and science students are frequently required to write laboratory reports, there is little printed information available about how to write such reports. Furthermore, every discipline, every course, and every professor seems to require a different format and style, and different kinds of laboratory experiments are often reported in different ways. Hence, it is impossible for this handout to describe one right way to compose a lab report.

What this handout does describe is a generally applicable format for the lab report, leaving you to adapt this format to your particular situation. That is, you can vary the format according to what is most appropriate for the lab work you're doing. Always check with your professor or TA about the specific format he or she desires.

Title Page
The title page provides the name of the lab experiment, the names of the lab partners, the date, and any other information your instructor requires.

Abstract
The abstract is the report in miniature. It summarizes the whole report in one, concise paragraph of about 100-200 words. As distinguished from the introduction, the abstract tells the reader what will be done and lays the groundwork Also, the abstract summarizes the report itself, not the actual experiment. Hence, you cannot write the abstract until after you've completed the report.

Before writing the abstract, it is often helpful to summarize each section of the report (introduction, methods and materials, procedure, results, discussion, and conclusion) in one sentence. Then try to arrange this information into a short paragraph. Remember, the abstract should be a precise and specific summary.

Introduction
Whereas the abstract summarizes the whole report, the introduction presents the subject of the report and acquaints the reader with the experiment. Typically, the introduction states the problem to be solved or the experiment to be performed and explains its purpose and significance. It also provides whatever background theory, previous research, or formulas the reader needs to understand and perform the experiment (or solve the problem). Usually, the instructor does not want you to repeat such information verbatim from the lab manual; you can simply make the appropriate references to the manual.

Methods and Materials (or Equipment)
This section can consist of a list. Be complete, accurate, and precise.

Experimental Procedure
This section is a full descriptive narrative. Be complete, accurate, and precise, listing all steps in the correct order. State what you really did and what actually happened, not what was supposed to happen or what the textbook said.

Results
Again, give your actual results, not what should have happened. Although results are usually presented quantitatively, you should always introduce each block of information verbally and provide clear and accurate verbal labels.

Discussion
In this section, you must explain, analyze, and interpret your results, being especially careful to explain any errors or problems. This is probably the single most important part of the report, since it is here that you demonstrate that you understand and can interpret what you have done.

Conclusion
Draw conclusions from the results and discussion that answer the question, "So what?" Then go on to explain your conclusions. In this section, you may also criticize the lab experiment and make recommendations for improvement. Such criticisms and recommendations, however, should focus on the lab as a learning experience; mere complaints about faulty equipment or amount of time spent are not appropriate.

Note: The results, discussion, and conclusion sections can be combined in various ways. Use whatever combination is most appropriate for your situation.

References
Some reports require references at the end. Use the correct forms for the particular field you are working in. Always consult your instructor about reference forms, and check a style manual for the field.

Appendices
Appendicies may include raw data, calculations, graphs, and other quantitative materials that were part of the experiment, but not reported in any of the above sections. Refer to each appendix at the appropriate point (or points) in your report. For example, at the end of your results section, you might have the note, See Appendix A: Raw Data Chart.