Pre-Laboratory Assignment Chemistry Articles

The Laboratory Report1,2

Authors: M. C. Nagan and J. M. McCormick

Last Update: August 10, 2012

 

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Introduction

The research paper is the primary means of communication in science. The research paper presents the results of the experiment and interpretation of the data, describes the rationale and design of the experiment, provides a context for the results in terms of previous findings and assesses the overall success of the experiment(s). Scientists working in industrial laboratories do not write as many journal articles as their colleagues in academia, but they routinely write progress reports, which take the same form as a journal article. So no matter what your career goals are, it is important that you become familiar with this style of writing.

There are set rules for preparing a journal article (or a laboratory report). The style requirements vary only slightly from journal to journal, but there are far more similarities than differences in the scientific writing style.  If you are writing an article for publication in a particular journal (or preparing a laboratory report in the style of a particular journal) you should consult the Instructions to Authors section of the journal’s website (this information is also included in the journal’s first issue of each year).

There are several style guides3,4  and articles5 to help scientists and students prepare their manuscripts.  The most useful of these to chemists is the American Chemical Society’s (ACS) ACS Style Guide, which may be found in the Truman library or may be purchased from the ACS web site. Because of the variation in journal styles, and the requirements for a specific course, your instructor will inform you of specific style requirements for his or her class. This guide is based on the Journal of the American Chemical Society style,6 and is meant to provide a good starting point for writing a laboratory report.  It is not meant to be the definitive style guide; you must adjust your style to your audience and the journal in which your results will be published.

General Editorial Issues

Although we shouldn’t, all of us are swayed by first impressions.  How your paper appears to the journal editor or reviewer is their first impression of your science, and it will color their impression of your results, if you let it.  Nothing is worse than a sloppily prepared paper with no page numbers, a font that can’t be read or which is full of grammatical errors.  Remember that everyone will assume that if you did not take the time to write your paper carefully, you did not take the time to do your science carefully.

The following are some general editorial guidelines to follow that will leave a good first impression with your readers.

1) Double-space your paper throughout (including figure captions and tables, too).
2) Use a reasonably sized font such as 12 point Times.
3) For figures, you may choose to use a sans-serif font for better graphics quality such as Arial or Helvetica.
4) Use at least 1” margins on all sides.
5) Number the pages. Place the page numbers in the top, right-hand corner, or centered on the bottom of the page.  Either style is acceptable and whichever one you choose remain consistent in your numbering scheme throughout the paper.
6) Do not start sentences with symbols or numbers; rather, spell out the full name of the symbol if it is used at the beginning of the sentence. For example, write “Alpha-lactalbumin” instead of “α-Lactalbumin” when beginning a sentence. Also spell out symbols or numbers in a title, except when part of a chemical name (e.g. 2-hexanol).
7) Spell check the document thoroughly.  Have someone, who will give you an honest and complete critique of your paper, read the paper.  Revise, revise, revise!

General Stylistic Issues

Uniformity of style is the key to scientific communication.  The journal editors, the referees who review a manuscript, and the journal readers who are interested in the results presented in a paper all expect certain things to be present in a manuscript and that they are in a certain order.  Just like the sloppy-looking paper, a paper that does not adhere to the expected style reflects poorly on the author, no matter how good the science is.

1) The paper should be written in a third person, passive voice. Occasionally, but rarely, it is appropriate to use “we” when describing the intention of the authors. It generally depends upon the intended subject of the sentence. Consider the two sentences below:
        a) Calcium solid (5 g) was poured into a beaker.
        b) We poured calcium solid (5 g) into a beaker.
In the first sentence (a), which is passive, the subject is the calcium solid. In the second sentence, the subject is the experimenters. In scientific articles, the subject is most often the science and not the experimenters.
2) Use the past tense in general (e. g., what was or has been done). However, use present tense when describing properties of molecules or organisms because they still have these properties.
3) Unless directed otherwise, assume the reader of your laboratory report is your peer, the average chemistry student, not the chemistry professor. Therefore, everything should be explained as if the reader knows some chemistry, but is not an expert in the subject of the paper. By no means does the reader know what you are doing, or why you are conducting your experiment. Think about what you would want to know about the subject if you were the reader.
4) Avoid repetition in language. Try not to start each sentence with the same construction and words.
5) Do not use quotes. Unlike humanities or literature papers, quotations are rarely found in scientific articles. However, it is appropriate to paraphrase other authors.
6) Explain technical terms.
Example
“Hemoglobin has a Hill constant, a value that describes the degree of cooperative ligand binding, of 2.8.”
7) Define abbreviations.
Example
“The official colors of Truman State University (TSU) are purple and white.”
8) Place a space between a number and a unit.
Example
“Sephadex (10 g) was combined with deionized H2O (100 mL) at 25 °C.”
9) Do not start a sentence with a number or “Figure 1” or “Table 1”, etc..
Correct: Milk samples (50 μL) were analyzed by high performance liquid chromatography under three different buffer conditions (Figure 1).
Incorrect: Figure 1 shows the high performance liquid chromatography chromatograms for the sample run under three different buffer conditions.
Incorrect: 50 μL of milk was analyzed by high performance liquid chromatography using three different buffer conditions.
10) There are three ways to refer to a paper in the text.
For example, the citation of the work authored by Jackson, A. K.; Wilson, R. S.; Houk, K. L.*, could appear in the text in any of the following ways.(Note that et al. is an abbreviation for et alia and that it is italicized because it is not English.7)
a) Jackson et al.
b) Jackson and coworkers
c) Houk and coworkers

In the last example we assumed that the author whose name is starred is the principle investigator on the project, and gave them more credit for the work.  Note that it is an American convention to list the principle investigators last, while many European and Japanese journals place them first.

Often there are two principle investigators, and in this case both should be mentioned.  For example, the work by Jackson, A. K.; Wilson, R. S.*; Houk, K. L.* should be referred to, in the format given in example (c) above, as “Wilson, Houk and coworkers”.  If there are more than two principle investigators, it is best to use either of the formats given in example (a) or (b), or to use some other wording to avoid this construction entirely.

Organization/Components

Sections

Sections should appear in your paper in the order described below. All sections but the title have the section explicitly labeled, usually in bold letters to differentiate it from the rest of the text, and left aligned on the page. A blank line should appear after the last word of the section to separate the various sections, but a line should not be placed after the section title.

1) Title/Title page
2) Abstract
3) Introduction
4) Experimental (Materials and Methods in some journals)
5) Results
6) Discussion
7) Conclusions
8) Acknowledgements
9) References
10) Tables
11) Schemes
12) Figure Legends
13) Figures
14) Supporting Information

Please note that you should not physically assemble your paper in this order. Instead, it is suggested that you compose: a) Materials and Methods, b) Figures, Figure Legends and Tables, c) Results, d) Discussion, e) Conclusions, f) Introduction and Schemes, g) Abstract, and h) Title. Then put all the sections together in the final paper in the order outlined above.

A template is available to help you organize your report.  Click here to learn more about it.

Subsections

It may be helpful to organize sections further into subsections. These subsections should have their own titles that are italicized and followed by a period.

Description of Paper Components

Title/Title Page

A title reflects the emphasis and contents of the paper. It tells the reader the paper’s topic and it also entices the reader to continue reading further. Therefore, it is not uncommon for the title to reveal the results or major conclusions of the experiment. Examples are given below. The title should be on its own page (the title page), left-aligned at the top of the page, in bold letters.  Note that in some journals the title’s font size is 2 points larger than the text (i. e., 14-point, if the rest of the paper is in a standard 12-point font).  However, this is not standardized and you should check with your instructor for which format he/she wants you to follow.

The title must be brief (2 lines maximum) and grammatically correct. Under the title, write your name and your professional address in italics (Department of Chemistry, Truman State University, 100 East Normal, Kirksville, MO 63501).

Example Titles
1) Determination of the Differential Fluidity of Water and Benzene by Viscosity Measurements
2) Purification of Alpha-Lactalbumin from Bovine Skim Milk by Immobilized Metal Ion Affinity Chromatography
3) Synthesis and Characterization of Potassium Tris(oxalato)ferrate(III)
4) Ionic Composition of Drinking Water Influenced by Pipe Materials: An Atomic Absorption Spectroscopic Analysis

Abstract

The abstract is a one-paragraph summary of the paper that is written in the present tense. As the abstract is the only part of the paper that is entered into article databases, it should be able to stand alone, separate from the paper. The first one to three sentences of the abstract should briefly introduce the reader to the problem studied. Next, the scientific approach, major results and primary significance of the findings should be presented. The abstract is generally 150-200 words (less for shorter papers). This section is normally written after the body of the paper. Because the abstract is separate from the paper, all abbreviations should be written out, or defined, and any references should be written out in full.  An example of how a reference might appear in an abstract is

Inhaled fumes from permanent markers have been shown to cause brain damage (Johnson, A. J. Permanent markers and the brain. J. Am. Brain. Res.2004, 18, 215–218).

Note that in some journals that inclusion of the title in a reference is not required (vide infra).

Introduction

The introduction should present the scientific problem at hand to the reader. Explain to the reader why the experiment was conducted, how it was designed and perhaps, if appropriate, what was found. Literature that is relevant should be incorporated and will help the reader understand the context of your study. A good rule of thumb is to start at the most general topic and progressively move towards the specific. Here is a general outline for an introduction:

I. Broad significance of the topic to the chemistry discipline and society in general
II. Introduction to the topic within chemistry
III. Description of the specific problem
IV. General goals and significance of the experiment or research topic

In this section, consider including figures, schemes and equations that complement the text.

While this is similar to the information that you should have written your notebook, the introduction to a paper is different than the background that you included for an experiment (or experiments) in your notebook.  Remember that you are trying to reach a larger, more general audience with your paper, and the introduction must be structured to draw the reader in and help them focus on your important results.

Experimental

The experimental section of your paper should be a logical, coherent recount of the experiment(s) conducted. This section should be complete enough for a trained scientist to pick up your report and replicate your experiment. The experimental section in a laboratory report is more concise than the corresponding section in the laboratory notebook. It should not be a step-by-step procedure of the activities carried out during the laboratory period.

The first paragraph of the experimental section contains information on key chemicals used in the procedure.  When the chemicals are used as received, there will usually be a statement to that effect and further details are not usually necessary.   You will list the chemical supplier’s name and the substance’s purity will be noted in cases where the chemical is hard to find, it is of a special purity or if there is only one supplier.  Do not list lot numbers. If a starting material was synthesized according to a literature procedure, then state this in the opening paragraph and reference the procedure. If purification or drying of the compounds is required, it is described here, also.

The first paragraph often will also list the instruments used to characterize the newly synthesized substances. All instruments and equipment should be specified including the model number of the instrument and the name of the manufacturer (serial numbers are not included). When a spectroscopic or physical method is the focus of the report, it will be described in its own subsection. You are not required to write the experimental in this fashion. 

For common techniques, laboratory textbooks should be referenced. However, if a previously published procedure was modified, then this is stated and only the modifications performed are included. If the procedure is your own, then outline the procedure with the main points, including details that are critical to replicating the experiment. These might include the type and size of your HPLC column, the buffer or the concentrations of chemicals.

When the syntheses of substances are reported, the synthetic procedure used to make each substance is described in its own separate paragraph. The paragraph begins with the name of substance, or its abbreviation (if the abbreviation was defined earlier in the paper), in bold face. If numbers are assigned to the compounds, these are also included (in parentheses). Often the synthesis will be written out, even when a literature procedure was followed. The mass and percent yields must be reported. Some of the new compound’s characteristics are included at the end of the paragraph describing its synthesis. These include: melting point range (and literature value, if known), elemental analysis (both calculated and found), selected peaks from the mass spectrum (with assignments), selected IR peaks (also with assignments), and any NMR peaks with their chemical shift, multiplicity and integration (you will often find the observed coupling quoted and the assignment of the peaks).  The following is an example of how to report a compound’s synthesis.

Tris-(2-pyridylmethyl)amine: To a stirred solution containing 10.11 g 2-pyridylmethyl chloride hydrochloride and 3.20 ml 2-pyridylmethyl amine in 20 ml H2O was added in a slow, drop-wise manner (~1 drop every 25 sec) a solution containing 5.03 g NaOH in 12 ml H2O so that all of the solution was added in about 1.5 hr. Upon complete addition of the NaOH, the reaction mixture was heated on a heating mantle to 70 ºC for 20 min. The cooled reaction mixture was then extracted four times with 50 ml CH2Cl2. The combined extracts were dried over Na2SO4 and the CH2Cl2 was removed using a rotary evaporator. The resulting red oil solidified upon standing. The red solid was then dissolved in a minimum of hot hexane. The yellow solution was decanted from a red oil which did not dissolve and filtered hot. Upon cooling the product crystallizes in large needles, which were recovered by filtration and air-dried. Recrystallization from hexane gave 2.08 g of the product (23% yield). The melting point of product is 85 ºC, sharp (literature 87 – 89 ºC).ref1H NMR (CDCl3, ppm): 3.89 (s, 6 H, methylene), 7.14 (m, J = 1.3, 6.1 Hz, 3 H, pyridyl), 7.58 (d, J = 7.8 Hz, 3 H, pyridyl), 7.63 (m, J = 1.8, 7.6 Hz, 3 H, pyridyl), 8.15 (m, J = 0.9, 4.9 Hz, 6 H, pyridyl). 13C NMR (CDCl3, ppm): 60.13 (methylene), 122.01, 122.97, 136.48, 149.06, 159.25 (pyridyl).

The experimental section has two quirky wrinkles on the general scientific style.  These are:

1) when citing previously published procedures, authors’ names are generally not included,
Correct “Purification of the bovine brain isolate was performed according to previously published procedures.ref
Incorrect “The previously published procedure of Jackson et al.ref was followed with modifications outlined below.”
2) when citing the use of a kit, pre-packaged-assay or other commercial equipment with directions, include just the company’s name in parentheses; it should not be a full reference.
Example
“The Bradford assay (Sigma) was carried out to determine the total protein concentration of the five protein isolates.

Results

In the Results section, the results are presented and summarized in a reader-friendly form. Raw data are not presented here. For instance, it is appropriate to include the average calculated concentration of a solution but not the original absorbance values that were collected from the spectrophotometer; that information is best left in your laboratory notebook.

 

Graphs and tables often make the data easier to interpret and more understandable (click here to review graph preparation). A graph is presented in the paper as a figure. In general, a graph or table is an appropriate representation of the data when more than 2 or 3 numbers are presented. Data that are presented in the form of a graph or table should be referred to but should not be repeated verbatim in the text as this defeats the purpose of a graph. More information on figures and tables is presented later.

 

The Results section also reports comparable literature values for the properties obtained and/or calculated in the paper. Observation of trends in the numerical data is acceptable. However, interpretation of the trend should be saved for the Discussion section.

 

Remember, do not simply report your numerical results.  The Results section must have a narrative that describes your results.  This narrative can include a description of the data (such as spectra or data in graphs), what problems were encountered during data acquisition (and how they were resolved, or not) and a general description of how the raw data were processed to give the final results (not a step-by-step description of everything you did).  The reader wants to know what you did, how you did it, what problems you encountered and finally what your results were.  Each of these topics must be addressed in the Results section in a way that is clear, yet concise.

 

Discussion

This is the section where the results are interpreted. This section of the paper is analogous to a debate. You need to present your data, convince the reader of your data’s reliability and present evidence for your convictions. First, evaluate your data. Do you have good, mediocre, terrible, or un-interpretable data? Evaluate your results by comparing to literature values or other precedents. Explain what results should have been obtained and whether you obtained these expected values. Note that even if expected results were not obtained, you did not fail. Unexpected results are often the most interesting. Perhaps your hypothesis was not correct. Why is this? What new hypothesis do your data suggest? If you feel that your results are not reliable, you need to explain why. Use statistical analysis or chemical principles to support your claims. Was there a systematic error? Is the error due to the limitations of your apparatus? Does your data look the same to within a standard deviation? Evaluate the statistical significance of your data (click here to review the statistical treatment of data). After validating your data, you should interpret your results; state what you believe your results mean. How do your results help us understand the scientific problem? What do your results mean in the context of the bigger picture of chemistry, or of science? How do your results relate to the concepts outlined in the introduction? Do not assume that your experiment failed or was successful. You need to prove to the reader, with logical arguments and supporting evidence, the value of your study.

 

The conclusions that you wrote in your laboratory notebook are a good starting point from which to organize your thoughts.  Your paper’s discussion section is structured very similarly to the conclusions section in your notebook, and it might be good idea to review that now (click here to review the structure of the conclusions in the laboratory notebook).

 

Conclusions

The Conclusions section is typically a one-paragraph summary of your laboratory report. Here you summarize the goal(s) of your experiment, state whether you reached that goal, and describe briefly the implications of your study. Note that in some chemistry sub-disciplines it is acceptable to combine the Discussion and Conclusions sections. Consult your course syllabus or check with your instructor on the specific format to be used in your class.

 

Acknowledgements

The Acknowledgements section is where you thank anyone who helped you significantly with the project or with the manuscript. For instance, you would thank your laboratory partners if they’re not authors on the paper, anyone who helped with the design of the experiment or the preparation of the paper. You might also include funding sources such as a Truman State University summer scholarship or a National Institutes of Health grant.

 

References

Most of the ideas presented in your paper are probably not exclusively yours. Therefore, you should cite other people’s work wherever appropriate. However, you do not need to cite information that is common knowledge or is exclusively your idea. The References section is a compilation of all citations made within the paper. It is not a bibliography and therefore should not list sources that are not directly referred to in the text.

 

References Format

The format of references varies amongst journals. For your chemistry laboratory reports, you should follow, by default, the ACS guidelines as outlined in The ACS Style Guide and Journal of the American Chemical Society, JACS (all examples given in this handout conform to JACS format). If your professor requires you to conform to a specific journal’s format, look at articles from that journal or refer to the journal’s “Instructions to Authors.” The specifications for most ACS journals are:

1) References should be compiled at the end of the paper in the References section.
2) References should be numbered in the order that they appear in the paper. For citations in the narrative, numbers should be superscripted and appear after the punctuation mark.
3) No empty lines should be inserted between reference entries.
4) This section should be double spaced just like the rest of your paper.
5) A reference is only listed once in the References section.  If multiple citations of the reference are made in the text, then the number corresponding to that reference is placed in the text each time.  The common abbreviations used in footnotes and references (e. g., op. cit., ibid.) are not generally used in scientific writing.

 

 

Types of References

Articles. Journal articles are the primary source found in laboratory reports. An example is given below. Notice that the authors’ initials are given instead of the first and middle names. Also, there is no “and” before the last author’s name. Some journals require that the article’s title be included in the reference (check with your instructor to see if he/she wants you to use this style).  When included, the article’s title should start with a capital letter but the other words in the title, unless they are proper nouns, should not be capitalized (see below). The journal title is abbreviated (click here for a list of the ACS abbreviations for common journals). Also, the year and the comma after the year are in bold. Lastly, the reference has inclusive pagination (first and last pages are given).

 

The following are examples of the same journal article with the first given in style where the article’s title is included in the reference, while the second is in the style where the article’s title is omitted.

(1) Bergmann, U.; Glatzel, P.; deGroot, F.; Cramer, S. P. High resolution K capture X-Ray fluorescence spectroscopy: a new tool for chemical characterization. J. Am. Chem. Soc.1999,121, 4926-4927.
(1) Bergmann, U.; Glatzel, P.; deGroot, F.; Cramer, S. P. J. Am. Chem. Soc.1999,121, 4926-4927.

Books. Books should be cited in the following manner:

(2) Brünger, A. T. X-PLOR Manual, Version 3.1: A System for X-ray Crystallography and NMR; Yale University: New Haven, CT, 1990; pp 187-206.
(3) Cheatham, T. E., III; Kollman, P. A. In Structure, Motion, Interaction, and Expression of Biological Macromolecules; Sarma, R. H. and Sarma, M. H., Eds, Adenine: New York, 1998; p. 99.

Computer Programs. Citations for computer programs vary. If a person in academia wrote the program, there is often a journal-article source. In other cases, the program is simply distributed by a company.

Journal Article
(4) Humphrey, W.; Dalke, A.; Schulten, K. VMD: Visual Molecular Dynamics. J. Mol. Graph.1996,14, 33-38.
Company Distribution
(5) Case, D. A.; Pearlman, D. A.; Cladwell, J. W.; Cheatham, T. E.; Ross, W. S.; Simmerling, C. L.; Darden, T. A.; Merz, K. M.; Stanton, R. V.; Cheng, A. L.; Vincent, J. J.; Crowley, M.; Ferguson, D. M.; Radmer, R. J.; Seibel, G. L.; Singh, U. C.; Weiner, P. K.; Kollman, P. A. AMBER version 5.0; University of California: San Francisco, 1997.
(6) Insight II; San Diego, CA: Molecular Simulations, 2000.

Websites. Journal articles are much preferred over websites. Websites are dynamic and are usually not peer reviewed. One of the only instances when a website is an acceptable reference is when it is referring to a database (however, an article is usually associated with the creation of the database). If you must use a website, the reference should include a title for the site, the author(s), year of last update and URL. It is unacceptable to use a website as a reference for scientific data or explanations of chemical processes.

(7) Cheatham, T. E., III Simulation Protocol for Polynucleotides; 1998, http://www.amber.ucsf.edu/amber/tutorial/polyA–polyT.

Tables, Schemes and Figures

Tables, schemes and figures are all concise ways to convey your message.  As you prepare these items for your report, remember to think of your reader.  You want them to derive the maximum amount of information with the minimum amount of work. Pretend to be the reader and ask yourself, “Does this enhance my understanding?”, “Can I find everything?”, “Can I read it without being distracted?” Poorly prepared tables, schemes and figures will reflect badly on your science, and you as a scientist, so think carefully about these items as you prepare your report.

 

Tables

A table is a way to summarize data or ideas in a coherent, grid-like fashion. This is notsimply output from a spreadsheet! You should prepare the table in a word-processor so that its formatting matches the rest of your report.  In general, tables have no more than ten rows and columns to avoid overwhelming the reader.  One common exception is in review articles (such as in Chemical Reviews) where an author is attempting to summarize results from an entire field.  Another common exception is in the reporting of X-ray crystallography data.  These tables have their own special formatting rules, and will not be discussed here.

 

Tables are referred to in the text as “Table #”. Tables, schemes and figures are labeled separately, with Arabic numbers, in the order they are referred to in the paper. Tables have a table caption, which in some journals appears above the table, while in others it appears below.  In either case, the table caption is always on the same page as the table.

 

Don’t use lines or boxes in your table except where absolutely necessary. Use spaces between your columns instead (helpful hint: it is better to use your word processor’s table formatting tools than trying to get the columns to line up using tabs or spaces). All column or row headings should have clear subtitles and units if needed (usually in parentheses). Any numbers that are presented should have proper significant figures, and an indication of the error should be shown (click here to review how to report uncertainty in one’s data). An example table is given below.

Table 1. Aminoacylation efficiency of duplexAla substrates containing base pair substitutions at the 2:71 position.

 

2:71 Base Pairkcat/KM (relative)aFold decreaseb-ΔΔG(kcal/mol)c
G:C (wild-type)10
Watson-Crick Pur:Pyr Base Pairs
I:C0.511.90.39
G:4HC0.253.90.81
2AA:U0.234.30.86
2AP:U0.185.61.0

 

aValues reported are averages of at least three determinations with average standard deviations of ±26%.
bFold decrease in kcat/KM is given relative to wild-type duplexAla.
cΔΔG is defined as RTln[(kcat/KM)variant/(kcat/KM)wild-type], where R=1.98272 cal/mol•K and T=298 K.

Schemes

A scheme is usually a sequence of two or more chemical reactions that together summarize a synthesis. A scheme may also show the steps in a purification with each step or reaction giving the reactants, products, catalysts, and yields.  A scheme that shows a chemical reaction may also show possible intermediates. Note that mechanisms are not usually conveyed using a scheme because they are more complicated and illustrate where electrons are proposed to move.  Mechanisms are most often placed in a figure.

 

It is a common convention in a scheme to write a bold number underneath chemical species referred to in the text.  Note that for the first occurrence of the bold number in the text, the chemical’s name is given, but after that only the bold number is used to identify it. This method of defining abbreviations for compounds can also be done in the experimental section, if there is no scheme.  This is very useful when a compound’s name is long or complicated.

 

The one-step yield is usually written to the right of the equation, although it is also proper to write the yield under the arrow.  Note also how the reaction conditions can be summarized (i. e., the first step below), which saves the reader from flipping to the experimental section for these details.

 

Each scheme also has a caption, which is included under the scheme.  The caption should briefly  summarize what is in the scheme.  If the scheme is from another source, the reference to this source should appear at the end of the caption.

 

The following is an example of a scheme that might appear in a synthetic paper.  The text below it shows how the scheme could be referred to in the body of the paper.  

 

Scheme 1. Synthesis of benzoyl chloride (3).

Benzamide (1) was refluxed under aqueous acidic conditions for 1 hour to yield benzoic acid (2). Acid (2) was then refluxed with SOCl2 to yield benzoyl chloride (3).

 

Sometimes a scheme may be used to illustrate a non-chemical process or how an instrument’s components are connected.  These could also be presented as figures, and there is no definitive rule that will tell you when to use a scheme and when to use a figure.  When in doubt, think of the reader and use the method that conveys the most information in the most easily understood format

 

Figures

Figures fall into two broad categories; those that are pictorial representations of concepts that are presented in the text, and those which summarize data. Again, it is critical to your report that your figures are clear, concise and readable, and that they support the arguments that you are making.  Remember that you must refer to and discuss every figure in the text!  If a figure is not mentioned, you don’t need it!

 

Figures that are pictorial representations of concepts usually appear in the Introduction, but it is also appropriate to include them in the Discussion. Use this type of figure to make your writing more concise (remember the conversion factor: 1 picture = 1 kword).  Remember, humans are very visually oriented and we can grasp complex concepts presented as picture more easily then when they are presented in words or as mathematical formulae.  Some examples of concept figures include:

1) An illustration of the deposition of metals onto a silicon wafer.
2) A diagram of the HIV life cycle.
3) A depiction of microwaves exciting water molecules.
4) A diagram illustrating the Frank-Condon principle.
5) A proposed organic mechanism.

Graphs are figures that present data.  You use a graph when you have more data than will fit in a table.  The general rules for preparing good figures for your notebook also apply in a laboratory report (click here to review graph preparation).  Formatting tips: do not use colored backgrounds or gridlines, and do not draw a box around the graph.

 

You may find it more concise to combine all your data into one graph. For example, it may be appropriate to put six lines with absorbance as a function of time, with varying concentrations of a reactant on the same graph rather than constructing six different graphs. However, when doing this, be careful not to over-clutter the graph.

 

Standard curves should not be included in this section unless that was the primary goal of the experiment. They should be put in the Supporting Information.

 

Figures have figure captions compiled in the Figure Legend section, located on a separate page at the end of the paper. Journals chose this format because of typographical issues, and it has been retained despite its inconvenience to the reader.  Each figure should appear on its own page in the order is it is discussed in the text. Figure captions appear in the Figure Legends section and do not appear on the same page as the figure. However, in the bottom, right-hand corner of the page the following identifying text appears:

“First author’s last name et al., Figure number”

Figure Legends

All figure legends (captions) should be found in the section entitled “Figure Legends”. The format for a figure legend is usually: “Figure number” (italics and bold), a short title (followed by a period) and then a description of what is in the figure. All figure legends are compiled on the same page separated by a blank line. Be sure to define in the caption any symbols used in the figure, and note whether lines that pass through data points are fits, or “guides to the eye”.

Example Figure Caption
Figure 1. Nucleic acid bases. The chemical structures of (a) adenine, (b) guanine, (c) cytosine, and (d) thymine.

Supporting Information

This section (also known as Supplemental Material) is where you can include information that may be helpful, but not essential, for evaluation of your data. Items in this section may include calibration curves, and spectra (from which you extracted only one absorbance value for your analysis).  Figures or tables of data whose contents were summarized in the text, or which were not critical to the conclusions, are also to be placed in the supporting information.  An example of this type of material is the table of atom positions generated in an X-ray crystal structure.

 

References

1. Click here to obtain this file in PDF format. (link not yet active)
2. Click here for an example of a completed laboratory report.
3. The ACS Style Guide; 2nd ed.; Dodd, J. S., Ed.; American Chemical Society: Washington, D.C., 1997.
4. Booth, W. C.; Colomb; G. G.; Williams, J. M. The Craft of Research The University of Chicago Press: Chicago, IL, 1995.
5. Spector, T. J. Chem. Educ.1994,71, 47-50. Click here to view as a PDF file (Truman addresses only).
6a. Journal of the American Chemical Society Instructions for Authors, 2007.
b. Inorganic Chemistry Instruction for Authors, 2007.
c. Chemical Reviews Instructions for Authors, 2007.
7.  Any non-English word should be italicized. This includes Greek and German words, and their abbreviations, that appear as part of chemical names (e. g., ortho-, meta-, para-, cis-, trans-, E-, Z-, alpha-, beta-, etc.).  Also italicized are the condensed forms of secondary (sec-), tertiary (tert-), etc. The primary exception to the rule for italicizing non-English words are the Greek and Latin prefixes that denote numbers in chemical names (e. g., mono-, bi-, tri-, etc.).  Some common Latin phrases that appear in scientific writing are vide infra (“see later”),vide supra (“see earlier”), et al. (abbreviation of et alia, Latin for “and others”), e. g. (from Latin exempli gratia, “for example”, not usually italicized) and i. e. (from Latin id est, “it is”, also not usually italicized). Other Latin phrases and abbreviations commonly used in footnotes and references (e. g., op. cit.) are not used in scientific writing.

Abstract

Introductory biology students are typically overwhelmed in the laboratory. Many of the students are unsure of how to prepare for each session. Two online pre-laboratory modules were developed to introduce the students to the concepts required for laboratory. The students studied the information in the modules and took an online quiz prior to each lab session. Of the 49 students who reviewed the first module and took the online quiz, the average quiz grade was 83.7% ± 12.8. A control group that did not review the online module had an average quiz grade of 53.6% ± 17.5. Of the 20 students who reviewed the second module and took the online quiz, the average quiz grade was 76% ± 15.0. The average quiz grade of the control group was 47.2% ± 16.5. The students were required to prepare laboratory reports for each session. Students who were required to review the modules received slightly higher grades on their laboratory reports compared to the control group. The students and faculty took a survey to determine their perceived impact of the modules on laboratory preparedness and performance. Both the faculty and students agreed that students are typically underprepared for lab (100% and 62%, respectively). Eighty-five percent of the students and all faculty felt that the modules did help them with preparation for the lab. Eighty-eight percent of the students and 76% of the faculty reported that the modules helped them to prepare their laboratory reports. These data clearly indicate that the pre-laboratory modules do enhance student preparedness and performance in the laboratory.

INTRODUCTION

At many colleges and universities, first-year undergraduate biology majors typically take introductory lecture/laboratory courses in which the laboratory component of the courses consists of several well-established “cook-book” experiments with known outcomes. These types of experiments are commonly used in the introductory laboratories because many of the first-year students have an underdeveloped basic biology knowledge base. In addition, the typical first-year student is experiencing a time of transition from an extremely structured learning environment that is common in the high school setting to an environment which requires them to take more personal responsibility for their own learning (1). Many of the students are overwhelmed by the transition and, as a result, are unsure of how to prepare for laboratory sessions. They often enter the laboratory with very little knowledge of the background information and/or experiments scheduled. Unfortunately, unless the students are thoroughly prepared for laboratory, they will be unable to perform the experiments and process the information they are required to learn from them (5). Effective pre-laboratory preparation enables the students to become more engaged, reduces student anxiety, and increases student confidence. Therefore, it is essential to ensure that first-year students learn how to effectively prepare for laboratory so that they can gain the productive experiences listed above (6).

Compounded with the lack of pre-laboratory preparation, many first-year students become quickly frustrated with the amount of information they are required to grasp during each laboratory session. During each session, students must demonstrate competence in following written and oral instruction, technical laboratory skills, observational skills, recording of results, and integrating the experiments with the topics discussed in the lecture component of the course. As a result of this frustration, some students become unable to follow the recipe-like instructions in the laboratory manual for the experiment. It is, therefore, not realistic to expect that overwhelmed and unprepared learners to be able to ascertain the underlying meaning behind each experiment they perform.

A vast majority of undergraduate educators support reform in science education that originates from “scientific teaching” – a teaching method that actively engages students in the process of science and demonstrates to them the rigor of the scientific disciplines (4). Due to its experiential nature, the typical undergraduate biology laboratory has always promoted an atmosphere of active learning which supports “scientific teaching”. Active-learning strategies in the laboratory may include such activities as small group work/problem solving, Web-based assignments, and analysis of data. Many active-learning techniques enable students to assimilate newly acquired knowledge in a small social setting (2, 3, 9). In using such techniques, students begin to develp higher order cognitive abilities that promote the conceptual reasoning skills required for progression through the undergraduate curriculum (1, 7, 10). In the scientific disciplines, active-learning techniques have aided in the enhancement of scientific literacy, retention, creativity, communication skills, self-evaluation skills, and preparedness for scientific research studies (1, 4, 8). Students who are unprepared for laboratory and frustrated during the laboratory session typically do not gain the benefits from the active-learning environment provided to them in the laboratory.

Consistent with the findings described above, over the past several years, Pace University-NYC introductory biology faculty have observed that their students are typically underprepared for the laboratory component of the course. In an effort to address the lack of BIO 101 student preparation for laboratory and the poor performance in the laboratory, two on-line pre-laboratory modules were designed using Microsoft PowerPoint® 2007 and multimedia supplied by both Benjamin Cummings Publishing and the Biology Project (University of Arizona, www.biology.arizona.edu). The two pre-laboratory modules that were developed introduced students to the key concepts and methods required to prepare for the BIO 101 “Determining the Properties of Enzymes” and the “Mendelian Genetics Using Corn and Carnations” laboratory sessions. These two laboratories were chosen for pre-laboratory module development and implementation because the students are required to prepare full laboratory reports in order to present, interpret, and discuss their findings following the laboratory sessions. As a result, evaluation of laboratory report grades could be used as an indicator of performance and understanding during the laboratory. After development, the pre-laboratory modules were uploaded onto the BIO 101 Blackboard® website and were made available for the students to review one week prior to the appropriate laboratory session. After the students reviewed the pre-laboratory module, they were required to take a quiz to determine their levels of preparedness. Upon completion of the quiz, the students were permitted to participate in the laboratory.

The goal of this study was to determine if the pre-laboratory modules enhance student preparedness and performance in the BIO 101 laboratory. To these ends, the grades that the students who reviewed the pre-laboratory modules received on the pre-laboratory quizzes and laboratory reports were evaluated and compared to the grades obtained on quizzes and laboratory reports of students that did not review the pre-laboratory modules. In both cases, the grades on the quizzes and laboratory reports were higher among the students that were required to review the pre-laboratory modules. Student and faculty survey results demonstrated that both groups felt that the pre-laboratory modules were beneficial to the students in the laboratory. The results from this study did indeed demonstrate that the pre-laboratory modules enhanced BIO 101 student preparedness and performance in the laboratory.

MATERIAL & METHODS

Pace University-NYC Introductory Biology

The introductory biology course for science majors at Pace University-NYC (BIO 101) is a large lecture-format course. It is the first course in a two semester sequence that introduces students to the basic principles guiding life. Topics covered in this course include basic chemistry, biological chemistry, enzymes and metabolism, cellular organization, Mendelian genetics, the chromosomal basis of inheritance, and an introduction to molecular biology. The course is composed of three different components: a traditional lecture with a typical enrollment of approximately 100 students (3 hours per week), a laboratory component (multiple sections linked to the lecture section with a maximum enrollment of 20 students; 3 hours per week), and a peer-led team learning discussion group component (multiple sections linked to the lecture section with a maximum enrollment of 10 students; 1 hour per week). The students are required to take all three components of the course simultaneously and grades from each component are considered when determining the final course grade for each student. Experiments performed in the laboratory and problem sets covered during the discussion group are directly related to the materials covered in the lecture component of the course.

Development and implementation of the pre-laboratory modules

Two 20- to 30-minute pre-laboratory module presentations were developed for this study. Both modules introduced students to the key concepts and methods required to prepare for the BIO 101 “Determining the Properties of Enzymes” and the “Mendelian Genetics Using Corn and Carnations” laboratory sessions. The modules were designed using Microsoft PowerPoint® 2007 and multimedia supplied by both Benjamin Cummings Publishing through the textbook for the Biology 101 course (Campbell and Reece, Biology 7th ed.) and the Biology Project Website (University of Arizona, www.biology.arizona.edu). Once completed, the pre-laboratory modules were uploaded onto the BIO 101 Blackboard® webpage and were made available for the students to review one week prior to their laboratory session.

Pre-laboratory module 1: “Determining the Properties of Enzymes”

For the experiment in the laboratory, the students are asked to prepare a crude extract from a turnip. The crude extract includes the enzyme peroxidase. The students are then required to determine the activity of the enzyme in the extract under different conditions (concentration, pH, temperature, and addition of an inhibitor) using a dye-coupled reaction and a visible light spectrophotometer. The pre-laboratory module for this experiment contains 17 PowerPoint slides and focuses on two topics required to understand the laboratory. The first is a basic summary of enzyme functioning and the factors that affect enzymatic activity. Along with the summary, the students are asked to review an animation to demonstrate how enzymes work. The animation is from the materials supplied by the BIO 101 textbook publisher, Benjamin Cummings Publishing (Campbell and Reece, Biology 7th ed). The second part of the pre-laboratory module presentation focuses on the dye-coupled reactions, the spectrophotometer, the theory guiding spectrophotometry (the Beer-Lambert Law), and how to use the machine and to interpret data from the machine.

Pre-laboratory module 2: “Mendelian Genetics Using Corn and Carnations”

This experiment teaches students about the principles of complete and incomplete dominance. The students are required to count corn kernel color (complete dominance) and carnation petal color (incomplete dominance). Once the students determine the numbers of corn kernels and carnations of different colors, they are asked to perform Chi squared analysis to determine if the numerical data they obtained were within an acceptable range compared to expected results (as determined by Punnett squares). The pre-laboratory module for this experiment contains 20 slides and focuses on two topics required to understand this laboratory. The first is a summary of the principles guiding complete and incomplete dominance. In addition to the reviewing the content in the module, the students are directed to answer questions related to complete and incomplete dominance on the Biology Project Website (http://www.biology.arizona.edu/mendeliangenetics). The second part of this pre-laboratory module focuses on using Chi squared analysis to interpret genetic data.

Online pre-laboratory quizzes

The two modules that were developed were linked to online pre-laboratory quizzes. The instructions in the pre-laboratory modules advised the students to make sure that they thoroughly reviewed and knew the materials in the modules prior to beginning the quizzes. Each quiz was administered through the Blackboard® platform and contained ten multiple choice questions related to the materials in the pre-laboratory modules. Several parameters were put into place to ensure that the students taking the quizzes were unable to go back and review the pre-laboratory module during the quiz for assistance with answering the questions. These parameters included: 1) Once a student began a quiz, they were required to complete the entire quiz; 2) The students were unable to go back once they completed a question; 3) Each question had a one-minute time limit; 4) Although the types of questions and the order of the questions remained the same for each student that took the quiz, the order of the answers for each question was scrambled for each student.

Assessment of the impact of the pre-laboratory modules on student preparedness for laboratory using pre-laboratory quizzes

During the Fall 2008 semester, there were seven laboratory sections associated with the BIO 101 course. The students enrolled in the seven laboratory sections were all in the lecture section that was taught by the author. There were six faculty teaching the seven laboratory sections; one faculty member taught two laboratory sections.

The seven laboratory sections were broken into two teams. One team consisted of three of the sections (Team 1) and the other team consisted of the other four laboratory sections (Team 2). The faculty member that taught two sections had one section on Team 1 and the other section on Team 2. On the first day of the lecture component of the course, the author informed the students that they should thoroughly prepare for each laboratory session. The author also informed the students that the laboratory instructors would, from time to time, give them pop quizzes at the beginning of some of the laboratory sessions to assess their preparedness. This information was also reiterated in the course syllabus. The students were not informed about the pre-laboratory modules on the first day of lecture.

One week prior to the “Enzyme” laboratory, the laboratory instructors working with the Team 1 laboratory sections told their students (n = 49) to review the online pre-laboratory module. They were then instructed to take the online pre-laboratory module quiz on Blackboard®. To gain access to the pre-laboratory module and quiz, the instructor gave them a unique password. The students were informed that they had to take the quiz in order to participate in the “Enzyme” laboratory session and that their grade on the quiz would be worth 10% of their laboratory midterm exam grade.

The Team 2 laboratory section students (n = 46) were not told about or given access to the “Enzyme” pre-laboratory module or quiz. These students were not given any additional instructions about preparing for the “Enzyme” laboratory session excluding the instructions that were given to them on the first day of lecture. Upon entering the laboratory for the “Enzyme” experiment, the students were given a pop quiz. The quiz was an identical paper version of the online quiz that the Team 1 students took. The students were informed that their grade on the quiz would be worth 10% of their laboratory midterm exam grade.

The identical procedure was followed for the “Mendelian Genetics” laboratory session, except that the two Teams were switched. The Team 1 students (n = 47) were not told about or given access to the “Mendelian Genetics” pre-laboratory module or quiz. They received the identical hard copy versions of the online quiz as a pop quiz at the beginning of the “Mendelian Genetics” laboratory session. The Team 2 students (n = 20) were told about and granted access to the “Mendelian Genetics” pre-laboratory quiz and module. They were informed that they had to complete the quiz prior to entering the laboratory. The grades on the quizzes were worth 10% of each student’s laboratory final exam grade.

Assessment of the impact of the pre-laboratory modules on student performance in the laboratory using laboratory reports

Each student was required to write up a formal written laboratory report for both the “Enzyme” and “Mendelian Genetics” laboratories. The students and faculty were given a rubric to assist with report preparation and grading. In addition, one of the discussion group sessions that runs prior to the “Enzyme” laboratory focuses on laboratory report preparation. The reports must include the following sections: Title, Abstract, Introduction, Materials and Methods, Results, Discussion, and Citations. For the Results section of the report, the students were required to present all of their data in table or graphical formats using Microsoft Excel®. The students were instructed to prepare the reports using primary scientific publications as models.

For this study, the grades on the “Enzyme” and “Mendelian Genetics” laboratory reports were compared between the two different Teams for each laboratory session. This information was utilized as an indicator of performance and understanding during the laboratory session.

Assessment of the perceived impact of the pre-laboratory modules on student preparedness and performance in the laboratory: Student surveys

In order to assess the perceived impact of the pre-laboratory modules on the students’ preparedness and performance in the laboratory, the students were asked to fill out an online questionnaire with Likert-type and yes/no questions. This questionnaire was a modified version of a Student Assessment of Learning Gains (SALG) survey designed by Dr. Victor Strozak of the Peer Led Team Learning Biology Task Force (information found at http://www.pltl.org). Likert-type questions require that students respond to a statement by choosing whether they strongly agreed, agreed, disagreed, strongly disagreed, or were neutral with respect to the statement. The types of questions on the survey included questions to evaluate the methods that the students used to prepare for the laboratory sessions that did not require review of the pre-laboratory modules, the students’ perceived level of preparedness for laboratory when they did not review the pre-laboratory modules, the students’ perceived level of preparedness for laboratory when they did review the pre-laboratory modules, and the students’ perceived notion of the impact of the pre-laboratory module on performance in the laboratory and laboratory report preparation when they reviewed the pre-laboratory module compared to when they did not review the pre-laboratory module.

Students were given 5 points extra credit on their lecture final exam for completing the survey. Seventy-two students filled out the survey but not every student answered every question. In this manuscript, the responses to five of the 12 questions asked on the survey are presented. The five questions described in this manuscript were discussed because they directly assess the students’ opinions of the impact of the pre-laboratory modules on their preparedness and performance in the laboratory.

Assessment of the perceived impact of the pre-laboratory modules on student preparedness and performance in the laboratory: Faculty survey

In order to assess the faculty’s perceived impact of the pre-laboratory modules on their students’ preparedness and performance in the laboratory, the faculty were asked to fill out a questionnaire with Likert-type questions. This questionnaire was a modified version of the student survey. The types of questions on the survey included questions to evaluate the faculty members’ perception of their students’ level of preparedness for laboratory when students did not review the pre-laboratory modules, the faculty members’ perception of their students’ level of preparedness for laboratory when students did review the pre-laboratory modules, and the faculty members’ perception of their students’ performance in the laboratory and laboratory report preparation when they reviewed the pre-laboratory module compared to when they did not review the module.

All six teaching faculty members filled out the survey. In this manuscript, the responses to five of the 12 questions asked on the survey are presented. The five questions described in this manuscript were discussed because they directly assess the faculty members’ opinions of the impact of the pre-laboratory modules on their students’ preparedness and performance in the laboratory.

Blackboard®

Blackboard® (http://www.blackboard.com/) is an educational platform that faculty can use to manage their courses online. It enables faculty to create a webpage for each course they teach. The webpage allows faculty to post files, administer exams, quizzes and surveys. It also enables faculty to post student grades using its grade book function and hold on-line course discussions. It was a powerful tool for this study because the pre-laboratory modules were posted to Blackboard® so that student usage of the modules could be easily tracked. The pre-laboratory quizzes were administered and graded using the Blackboard® platform. Finally, the student and faculty surveys were administered and the results tabulated by the Blackboard® survey manager.

Statistical analyses

One analysis involved comparison of the results related to the method of presentation of the quizzes. The grades that the students received on the on-line pre-laboratory quizzes were compared to the grades obtained with the hard copy versions of the same quizzes for both pre-laboratory modules using the Mann-Whitney U-test. This nonparametric test was used because the variances of the quiz grade data were not equal for both groups. The p-values from the Mann-Whitney U-test for both the “Enzyme” and “Mendelian Genetics” pre-laboratory quizzes are noted in Table 1. A p-value ≤ 0.05 was considered to be statistically significant.

TABLE 1

Comparison of quiz grades between the students who reviewed the pre-laboratory modules and students who did not

Another analysis assessed laboratory report results for students that reviewed and did not review the pre-laboratory modules. An unpaired t-test was used to compare the laboratory report grades between the students that reviewed the pre-laboratory modules and the students that did not review the modules for both the “Enzyme” and “Mendelian Genetics” laboratories (Table 2). Again, a p-value ≤ 0.05 was considered as statistically significant.

TABLE 2

Comparison of laboratory report grades between students who reviewed the pre-laboratory modules and students who did not

For the SALG survey, the student responses (strongly agree, agree, disagree, strongly disagree, or neutral) to five representative questions were reported as the averages of the responses for each question (Table 3). For the faculty SALG survey, the faculty responses to five representative questions were also reported as the averages of the responses for each question (Table 4).

TABLE 3

Student responses to five questions on the Student Assessment of Learning Gains (SALG) Likert survey (n = 72)

TABLE 4

Faculty responses to five questions on the Student Assessment of Learning Gains (SALG) Likert survey (n = 6)

Pace University Institutional Review Board approval for these studies was granted in August 2008.

RESULTS

Evaluation of pre-laboratory quiz grades to assess the impact of the pre-laboratory modules on student preparedness for laboratory

One week prior to the “Enzyme” laboratory, the laboratory instructors working with the Team 1 laboratory sections told their students (n = 49) to review the on-line pre-laboratory module and take the on-line pre-laboratory module quiz. The Team 2 laboratory section students (n = 46) were not told about or given access to the “Enzyme” pre-laboratory module or quiz. The Team 2 students were not given any additional instructions about preparing for the “Enzyme” laboratory session. Upon entering the laboratory for the “Enzyme” experiment, the Team 2 students were given a pop quiz. The quiz was an identical paper version of the on-line quiz that the Team 1 students took. The identical procedure was followed for the “Mendelian Genetics” laboratory session, except that the two Teams were switched. The Team 1 students (n = 47) were not told about or given access to the “Mendelian Genetics” pre-laboratory module or quiz. They received the identical hard copy version of the on-line quiz as a pop quiz at the beginning of the “Mendelian Genetics” laboratory session. The Team 2 students (n = 20) were told about and granted access to the “Mendelian Genetics” pre-laboratory quiz and module.

The grades that the students obtained on the two quizzes appear in Table 1. For both the “Enzyme” and “Mendelian Genetics” laboratories, the students that were required to review the pre-laboratory modules performed better on the quizzes than the students that did not review the pre-laboratory modules. The students that reviewed the pre-laboratory modules received grades of 83.7% ± 12.8 (n = 49) and 76.0% ± 15.0 (n = 20) for the “Enzyme” and “Mendelian Genetics” quizzes, respectively. The students that did not review the pre-laboratory modules and took the paper pop quiz in the laboratory received 53.6% ± 17.5 (n = 46) and 47.2% ± 16.5 (n = 47) on the “Enzyme” and “Mendelian Genetics” quizzes, respectively. The differences between the quiz grades received by the students that reviewed the pre-laboratory modules versus the students that did not review the modules were considered statistically significant. These data suggest that the pre-laboratory modules do indeed enable the students to better prepare for laboratory sessions.

Evaluation of laboratory report grades to assess the impact of the pre-laboratory modules on student performance in the laboratory

The “Enzyme” and “Mendelian Genetics” laboratories were chosen for this study because the students are required to prepare full laboratory reports in order to present, interpret, and discuss their findings from the laboratory sessions. As a result, evaluation of laboratory report grades between the two different teams could be used as an indicator of performance and understanding during the laboratory.

The students that reviewed the pre-laboratory module for the “Enzyme” laboratory received an average grade of 89.8% ± 7.73 (n = 42) on their laboratory reports, whereas the students that did not review the module receive an average grade of 86.8% ± 12.6 (n = 44) on their reports (Table 2). The students that reviewed the pre-laboratory module for the “Mendelian Genetics” laboratory received an average grade of 90.5% ± 11.5 (n = 20) on their laboratory reports, whereas the students that did not review the module received an average grade of 83.6% ± 16.0 (n = 39) on their reports (Table 2). Although neither set of data can be considered statistically significant, the students that reviewed the pre-laboratory modules did receive slightly higher grades on their laboratory reports. This suggests that the pre-laboratory modules did indeed have an impact on student understanding and performance in the laboratory.

Evaluation of the BIO 101 students’ impressions of the impact of the pre-laboratory module on their preparedness and performance in the laboratory

At the end of the Fall 2008 semester, the BIO 101 students were asked to complete a Likert survey to describe their perceptions on the impact of the pre-laboratory modules on their preparedness and performance in the laboratory. The results to the five most pertinent questions on this survey are depicted in Table 3. Of the 72 students who took the survey, 7.1% of them strongly agreed or agreed that they reviewed the laboratory manual each week (excluding the week that they were assigned to review the pre-laboratory module) and that they were frequently thoroughly prepared for laboratory. Just over 85% (85.3%) of the students strongly agreed or agreed that the pre-laboratory modules helped them prepare for laboratory. In addition, 80.9% of the students that took the survey strongly agreed or agreed that the pre-laboratory modules helped them to understand why each step of the experiment was performed in the laboratory. A vast majority of the students (88.2%) felt that the pre-laboratory modules enabled them to prepare their laboratory reports with greater ease. Finally, 82.4% of the students felt that the pre-laboratory modules were more helpful in preparing them for laboratory than if they were to simply read the laboratory manual prior to the laboratory session. The student responses to the survey questions indicate that, overall, the students found the pre-laboratory modules beneficial and that the modules helped them to better prepare for and perform in laboratory sessions.

Evaluation of BIO 101 faculty impressions of the impact of the pre-laboratory module on their students’ preparedness and performance in the laboratory

The BIO 101 faculty were asked to complete a Likert survey similar to the student survey. The faculty survey sought to determine the faculty’s perceptions of the impact of the modules on their students’ preparedness and performance in the laboratory. The results to the five most pertinent questions on this survey are depicted in Table 4. Of the six faculty members that took the survey, none of them felt that their students reviewed the laboratory manual each week. They all agreed that their students were frequently unprepared for laboratory. Fifty percent of the faculty agreed that the pre-laboratory modules helped their students understand why each step of the experiment was performed in the laboratory. The other half were neutral with respect to whether or not the pre-laboratory modules helped their students understand why each step of the experiment was performed. Fifty percent of the faculty felt that the pre-laboratory modules enabled their students to prepare their laboratory reports with greater ease. In contrast, 16.6% and 33.3% of the faculty were neutral or disagreed, respectively, that the modules helped the students prepare their laboratory reports. The faculty unanimously agreed that their students were more prepared for laboratory after they reviewed the pre-laboratory modules. Finally, 100% of the faculty felt that the pre-laboratory modules were more helpful in preparing their students for laboratory than if the students were to simply read the laboratory manual prior to the laboratory session. The faculty responses to the survey questions indicate that, overall, they felt the pre-laboratory modules enhanced their students’ preparedness for and performance in the laboratory.

DISCUSSION

The goal of this study was to determine if pre-laboratory modules enhanced student preparedness and performance in the BIO 101 laboratory. To these ends, the pre-laboratory quiz grades and laboratory report grades that the students who reviewed the pre-laboratory modules received, were evaluated and compared to the grades received by the students who did not review the pre-laboratory modules. In both cases, the grades on the quizzes and laboratory reports were higher among the students who were required to review the pre-laboratory modules. Student and faculty survey results demonstrated that both groups felt that the pre-laboratory modules were beneficial to the students in the laboratory. The results from this study did indeed demonstrate that the pre-laboratory modules enhanced BIO 101 student preparedness and performance in the laboratory.

For the “Enzyme” pre-laboratory quiz, there was a 30 percentage point grade difference between the students who reviewed the modules and the students who did not. There was a 28.8 percentage point grade difference between the students who reviewed the modules and those who did not for the “Mendelian Genetics” quiz. For both laboratories, the students who were not required to review the pre-laboratory modules prior to the laboratory failed the paper version of the pre-laboratory quizzes. These stark grade differences clearly demonstrate that not only did the pre-laboratory modules enable the students to better prepare for the laboratory, but the differences also confirmed that the students who were not required to review the modules did not prepare for the laboratory at all. Some students did read over the laboratory manual but did not comprehend what they had read.

The differences in grades on the laboratory reports between students who reviewed the modules and students who did not were not as apparent as the differences in grades on the pre-laboratory quizzes. This may be due to the fact that the students who did so poorly on the quizzes realized their deficiencies and sought out additional means (such as extra help with the laboratory professor or discussion group peer leader) to gain assistance with laboratory report preparation. Despite these possible additional efforts, the laboratory report grades for those students who did not review the modules were slightly lower than the grade for those students who did.

The student and faculty Likert surveys clearly indicated that both the students and faculty felt positive about the impact of the pre-laboratory modules on students’ preparation and performance in the laboratory. Both surveys also included an open-ended question asking for additional input and comments. Some student comments that support the assertion that the pre-laboratory modules were beneficial include:

“I think the pre-lab module helps the student understand the lab much better and he/she can actually perform the lab and know what to do instead of being lost during the experiment.”

“The pre-lab module/quizzes really helped me out with the lab and the lab report. It actually made me sit down and study what was going to happen in class. If I would have not had the pre-lab module and everything, then I would have never read the lab book to prepare for the lab. I would definitely recommend this practice for future lab classes in the following years to come.”

“I found the pre-lab module to be extremely helpful when it came to the lab report. I found that it was the most effective way to ensure that I was prepared for lab.”

The faculty also provided some comments that support the usage of the pre-laboratory modules. Some comments are as follows:

“The pre-lab module made the students focus more on the topic than usual.”

“The pre-lab module enhanced the long-term memory of the students. I definitely saw improvements. The modules facilitated the students with respect to quickly responding to the materials in the laboratory.”

“It was clear that the students were better prepared for the laboratory. They were more engaged during my lecture and appeared to be interested in performing the experiment.”

In summary, the pre-laboratory modules positively affected the learning experiences for the students enrolled in the Biology 101 laboratory. The students came to the laboratory prepared, they were more active participants during the laboratory, and their performance on the laboratory reports was enhanced. The student grades and faculty/student survey responses each support the further expansion of this program. As such, pre-laboratory modules and quizzes are currently being developed for every Biology 101 laboratory session at Pace University-NYC.

Acknowledgments

I would like to thank the faculty and students enrolled in the Fall 2008 Biology 101 course for their assistance and participation in this study. This work was previously presented at the 15th Annual American Society for Microbiology Conference for Undergraduate Educators in Beverly, Ma. I would like to thank Dr. Richard Schlesinger for his assistance with the statistical analyses and Ms. Erica Kipp for her critical review of this manuscript.

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