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WRITING INTHE SCIENCESThis publication was prepared by the staffand Peer Helpers of the Learning Commons.
About our cover:When the University of Guelph was incorporated in 1964, theinstitution adopted the name and some of the history of theCity of Guelph. Guelph’s name comes from “Welfen,” the familyname of the royal House of Hanover. That ancestry isrecognized by the white Hanovarian stallion which appears onthe University of Guelph’s official crest and in this 1981painting by Heather Cooper. The original painting still hangs inthe University Library, depicting the Hanovarian stallion withthe winged horse, Pegasus, the symbol of poetic inspiration. The University of Guelph, 2004, 2005
ContentsIntroduction. 1The Purpose of Scientific Writing.2Content and Form.3The Research Article .5The Lab Report .8Title.8Abstract.9Introduction .10Materials and Methods .11Results .11Discussion .13References .14Other Types of Student Writing. 21The Literature Review .21Critical Review of a Journal Article.36The Abstract .45The Poster Presentation .48
Making a “Science” of Scientific Writing.51Make Your Writing Familiar to Your Reader . 51Keep Subjects Close to Their Verbs. 52Emphasize Important Information. 54Set a Context for the Important Information . 55Focus Your Sentence Action . 57Grammar and Scientific Style. 59Use of First Person (I, We). 59Use of the Passive Voice. 61Avoid “Creative” Language and“Value Judgements”. 62Recognise Shifts in Verb Tense . 63Make Your Writing Concise, Preciseand Simple. 65Common Writing Faults. 67The Sentence Fragment . 67Conjunctions. 68The “However-Semicolon” Disease andConjunctive Adverbs . 69Keeping Verbs as Verbs . 70The Revision Process .71References . 74Appendix 1 . 76Lab Report Revision Checklist. 76
IntroductionSurely the scientist, of all people, is under the obligation to write notonly so that he may be understood, but so that he cannot bemisunderstood.E.H. McClelland (1943)It might be reasonable to assume that if you are a sciencestudent you will not have to do a lot of writing in your universityscience courses. Essays and book reviews for English literature,position papers for political science or history, and expositions ofphilosophical arguments are expected in the arts. In contrast, inbiology, chemistry, physics and mathematics, scientists carry outexperiments, analyze data, make calculations, design computersoftware, and account for and explain technological and naturalphenomena. So you may think that writing is not important in thesciences.However, writing is not restricted to the arts andhumanities. Language and writing are used by scientists andscience students to communicate their findings and explain theirresearch results: it is necessary to convert collected data intosentences. Having worked hard on the scientific and technicaldetails of their research, scientists must then work hard onproducing words to explain that research clearly and efficiently toothers so their research “cannot be misunderstood.” For example,a biologist might need to express the results of an experiment inwhich Dictyostelium discoideum was essential in learning that1
cytoskeletal proteins have overlapping functions and an engineerthe feasibility of building a special computer to monitor cardiacoutput by non-invasive means.In addition, scientists frequently write to explain ordebate the ideas and writing of other scientists, as well as writingscience for non-experts in more “popular” and general-interestpublications such as Canadian Geographic, Time, Sierra Club GreenGuide, Popular Mechanics, or the local newspaper. In fact, accordingto statistics at San Diego State University, careers in technical andscientific communication are among the top ten fastest growingfields in the United States.When asked to rank skills that a biologist must possess,biotech companies place effective communication second only torelevant work experience and ahead of other factors such asscience background, grade-point average and references. It isfitting, therefore, that Robert Barass (1991) entitled his bookScientists Must Write: A Guide to Better Writing for Scientists, Engineers,and Students.And science writing has been steadily increasing: theeditor of one scientific journal notes that scientific articlessubmitted for publication to his journal have increased in pagelength from an average of 5.4 pages in 1989 to 6.5 pages in 1997(Harris, 1998). As noted by this editor, and in all of the casesabove, it is apparent that scientists must write clearly, briefly andsimply.The Purpose of Scientific WritingAll writing has a purpose or purposes — to inform, toentertain, to persuade, to inspire, to justify, to instruct. Whileessays generally do many of these things at once, scientific papers2
are primarily intended to inform. Scientists depend on writtenscientific communications to keep up with what is happening intheir field and to communicate research results to others.Science investigates natural phenomena and attempts tounderstand and systematize them by observing events and testinghypotheses created to explain them. The research process beginswith a question — an hypothesis — around which an experimentis designed. The experiment is not intended to “prove” anhypothesis but to test it to determine the extent to which theresults support that hypothesis. Sometimes, the results of theexperiment do not support the claims of the hypothesis; “rulingout” an hypothesis is an important stage in discovering the truenature of phenomena. Only when the experiment can beduplicated and when best efforts fail, time after time, to disprovethe hypothesis, can the hypothesis be said to be supportable andthe results “true.”The scientific method determines what is consideredimportant in scientific writing. Effective research based on thismethod avoids vague hypotheses and unfocused data collection;in the same way, effective scientific writing conveys informationin a clear, accurate and organized way.Content and FormAlthough you cannot realistically separate content and formin scientific writing, sometimes it is useful to think of the writingprocess as having these two basic components — both must begiven due consideration.3
ContentFormThe ‘science’ of your writing:biology lab report, researcharticle, review of literature,annotated bibliography, abstractof an experiment.The style, language, andphysical format (as well asbibliographic format) used topresent or communicate yourdocument to its intendedaudience.Scientists and science students perform their day-to-daybusiness in physical, tangible ways: through observation andmeasurement; they perform experiments, design research trials,and analyze data. However, what they learn or discover, and whatactions they take (or recommend be taken), are usuallycommunicated in written form.Michael Alley, a scientist and researcher of scientificwriting, breaks down writing and language to an even greaterdegree:In writing, language is the way that words are used. Language isword choice, the arrangement of phrases, the structuring ofsentences and paragraphs, and more. In scientific writing, languageincludes the use of numbers, equations, and abbreviations; itincludes the use of examples and analogies (1987, p 25).So, on one hand, assume that science is communicated vialanguage and that we cannot think of content and form asdiscrete, separable units; on the other hand, however, it is alwaysuseful to divide and conquer any writing task that lies ahead ofyou: think both about the “content” of your writing and the“form” it will take.4
The Research ArticleAs an undergraduate science student, there is oneorganizational structure with which you should become familiar,the one that is most commonly used in scientific disciplines toreport experimental research. The research article is divided intosections that parallel the experimental process.This structure is called IMRAD (Introduction, Methods,Results and Discussion). The different sections allow readers toquickly identify what they are looking for and to follow, in alogical manner, the work done by the author.Your undergraduate writing assignments may include labreports, literature reviews, journal article critiques, posterpresentations and abstracts. To complete these assignmentssuccessfully, you must have a good understanding of the purpose,structure and content of research articles.The table following outlines the type of informationscientific readers will expect to find in each of section of theresearch article.5
6TitleThe Title is not a section but it is important as it is often thefirst thing read. It should indicate the topic of the researchand provide key words for indexing.AbstractThe Abstract is a clear, concise summary of the entire paper.It should include the question(s) investigated, theexperimental design and methods used, the major findings,and most importantly, a statement of conclusions.IntroductionThe Introduction provides the rationale for the experiment. Itdescribes the problem to be investigated, providing thecontext, key terms and concepts so that the experiment canbe understood. It also reviews the relevant research to providea rationale for the experiment – what findings of others arebeing challenged or extended. It then outlines the hypothesesand research questions.Materials & MethodsIMRAD Structure for Scientific Research ArticlesThe Methods section describes the steps followed inconducting the research and the materials used at each step.It is not only useful to readers who want to know whatmethods were used and how this may have influenced theresults, but also to those who are interested in replicatingand reproducing the study. Consequently, it should besufficiently detailed to allow them to do so.
ResultsDiscussionReferencesThe Results section should present only results which relateback to the question posed in the Introduction (thehypothesis). It functions as a stepping stone to theDiscussion section by presenting the framework on which theDiscussion can be built.The Results section will present the findings of the research inboth figures and in written text. Figures (graphs, tables anddiagrams) present the complete findings in visual andnumerical terms, while the accompanying text helps thereader to focus on the most important aspects of the resultsand to interpret them.This section is generally considered to be the most difficultpart to write and it calls on the skills of the researcher tointerpret the results obtained.It presents an argument, or set of arguments, about thesignificance of the results, about any limitations or problemswith research design or implementation and consequentproposals for future work.This section should include the references actually cited in thebody of the paper.7
The Lab ReportThe lab reports you will write as an undergraduatestudent are modeled on research articles; however, there are somedifferences: The scope and complexity of the research article isgreater than that of the lab report, particularly in theIntroduction, Results and Discussion sections. Forexample, the Introduction of the research article willusually include a literature review that summarizes theprevious research that has been done in the area beinginvestigated. In a lab report, this literature review willprobably not be so extensive; The audiences for the research article and the lab reportare also different. The research article is written forresearch scientists who are specialists in their field,whereas the lab report is written for instructors or fellowstudents.The format of the lab report is usually specified for eachcourse. However, the general format given below may serve as aguideline (see Appendix 1 for a Lab Report Revision Checklist).TitleThe Title of the lab report should indicate exactly whatyou have studied. For example, a title such as “The effects of8
light and temperature on the growth of the bacterium, Escherichiacoli ”* explains1.the environmental factors manipulated (light andtemperature),2.the parameter measured (growth), and3.the specific organism used (E.coli).It is unnecessary to use words like “A study on the effect of ”or “A report on the ”* Note that any specific organisms named should always beitalicized.AbstractThe Abstract is a brief summary of your entire lab report(about 250 words). It belongs at the beginning of your report,before the Introduction. It is always written last, since it includesyour main results and conclusions. Begin the Abstract with a brief, but specific, backgroundstatement to introduce your report. State your main purpose or objective and hypothesis. Describe the important points of your methodology(species/reagent/ingredient, the number of subjects orsamples and technique or instruments used to make themeasurements). Summarize the main results numerically and qualitatively(include standard errors and p values as required). Summarize the main points from the conclusion. Focuson the ones that directly relate to yourhypothesis/question.9
Use the past tense to describe the work and what wasfound; use the present tense for what is currently true.IntroductionThe Introduction provides the background information thatthe reader needs to understand your experiment (based onprevious work and/or theory). The information that you providefor the reader will form the basis or foundation for yourhypothesis. In the Introduction: Introduce the general area of science that your reportdeals with and explain why research in this area isimportant or relevant. Review the key concepts that are necessary for anunderstanding of the research that you are going toreport on. Develop the scientific context. Review the currentliterature on the topic in order to provide a context forthe hypothesis. State the hypothesis or purpose/aim of your research.Use the present tense most of the time, but the presentperfect and past tenses where logic demands. Resources such asyour textbook, course notes, research articles can be used todetermine the scientific concepts that are relevant to yourresearch and to build the scientific context. Don’t forget toreference them.10
Materials and Methods(also called “Methods,” “Procedure,” or “Procedural”)This section presents, in a logical order, the materials usedand the procedure(s) by which the experiment was performed.Describe what you did, using complete sentences andparagraphs, in the order that you did it (do not list). Include thematerials (and quantities) as you use them (do not list them). Provide enough information and detail for someone elseto reproduce your experiment.*Note: instructors will often ask you to write “pleaserefer to the lab manual” and when you do this, referenceit. Always document any changes that were made inprocedures. Name all chemicals/reagents used (full name) andquantities with standard (metric) units. Use the past tense and the passive voice. For example:“Exogenous DNA was introduced ”ResultsThis section is the “core” of the report. After reading theAbstract of a research article, professional scientists will thenconcentrate on this section. A well-written and well-organizedResults section provides the framework for the discussionsection.The Results section should accurately report and describeall the data you have collected so that the conclusions you drawwill be understandable to the reader. Do not interpret the datahere.11
Present your data in the form of percentages, averages,totals and so on. Put your raw data in an Appendix at theend of the report. Use tables and graphs to present your data. Don’t forgetto refer to the tables, graphs, diagrams in the text. Summarize in sentences the highlights — trends,maximums, minimums, changes — of the tables andgraphs. Present sample calculations in a separate section titled“Calculations” or in an Appendix at the end of thereport. Use the past tense.Tables & Figures Introduce each table or figure within the text and use thecomment to point out the highlights.e.g. The temperature increased on the third day (Figure 1). Number each table and figure and provide selfexplanatory titles so that the reader can understand theircontent without the comment.e.g. Table 1. Percent of soybean plants exhibiting visible injuryafter exposure to acid precipitation.12 Assign numbers to tables and figures in the order they arementioned in the text. Number the tables and figures independently of eachother. For example, the first table used in the lab report isTable 1, the second table is Table 2, and so on. The firstfigure used in the text is Figure 1, the second figure used
is Figure 2, and so on. This means you could have a Table1 followed by a Figure 3; a Figure 4 followed by a Table 2. Refer to tables as tables and all other items (graphs,photographs, drawings, diagrams, maps, etc.) as figures. Put the title for tables at the top of the table; put the titlefor figures at the bottom of the figure.DiscussionIn this section you must analyze and interpret yourresults. One way to get started is to try to answer the question“What do these results mean?” in relation to the experiment’spurpose. The following specific questions may assist you: What (if any) are the major assumptions implied in yourexperiments? Do the results meet the experiment’s objectives? Do the results agree with expected results or withprevious findings as reported in the literature? If not,how can you account for the discrepancy between yourresults and those expected? What may be wrong withpublished data that contradicts your results? What, if anything, may have gone wrong with yourexperiment, and why? Was there any source of error? Could the results have more than one explanation? Did the procedures you used help you to accomplish thepurpose of the experiment?13
Does your experience with this experiment suggest abetter method for the next time? Could another experiment be devised that maycorroborate your result?(Gilpin & Patchet-Golubev, 2000, p. 21)Write down the answers to the above questions in pointform. You then have to decide how you are going to organize thisinformation. The following suggestions might assist you: One way to begin the Discussion section is by referring toyour original hypothesis and accepting or rejecting it onthe basis of what you have found. Then discuss the results, but first establish some kind oflogical order for presenting them. This order may besimilar to the one used in the Results section. Try and support your interpretations of the results withwhat is known in the literature. Write a conclusion at the end of your discussion of theresults. Following the conclusion, you might want to discuss anyfurther questions that the research raises.ReferencesScientific lab reports are written for the sole purpose ofsharing information. If readers want more information aboutwhat you’ve written, they need to be able to find the exact source.The reference page at the end of the report allows the reader todo this. References also give credit to the person who did thework and provide your work with authority.14
Always reference your lab manual, lecture notes and anyjournal articles used. The textbook is usually referencedas well. Never use direct quotations in your report; alwaysparaphrase and give citations. Consult your course instructors, lab manual, and courseoutline for proper referencing format. Many courses willspecify the format of a particular journal.The following sample biology lab report illustrates thelanguage and structure of a typical lab report. References in thissample are formatted using APA style. This is a guide only; alwayscheck with your instructor for the specific course requirements.15
EXAMPLE OF A LAB REPORT IN BIOLOGY:The effects of pH on the rate of starch breakdownby the enzyme amylase.IntroductionAmylase is present in both animals and plants where itintroductionmoves fromcatalyzes the breakdown of starch into dextrin and maltose.general to specificIn animals this process occurs in the mouth and the smallintestine, and in plants the products of starch breakdownare utilized during seed germination (School of BiologicalSciences 1994).Water hydrolyzes starch to produce smaller molecules(sugars), but the rate of reaction is very slow. Amylaseincreases the rate of hydrolysis by lowering the activationenergy of the reaction. It forms a complex such that starchmolecules fill active sites on the surface of the enzymemolecule. The presence of the enzyme increases the rate ofstarch breakdown, but the enzyme itself is not changedreferences to whatduring the reaction (Purves et al., 1992).is knownEnzymes are very sensitive to conditions in theirenvironment (e.g. temperature), since changes in conditionsrelationshipbetween what isknown and presentresearchestablishedstatement ofpurposemay alter their molecular structure. If this occurs, the activesites may not be available for the substrate molecules, andhence catalysis will not occur. pH is known to affect theability of enzymes to catalyze reactions (Purves et al., 1992).This experiment was conducted to determine the optimumpH at which amylase catalyzes starch breakdown. Thehypothesis to be tested was that the enzyme would showhypothesisoptimal activity at pH 7, since it was extracted from pigpancreas, and the normal pH of the pig gut is 7 (School ofBiological Sciences, 1994).16
MethodsA calibration curve was prepared to determine therelationship between starch concentration and absorbancereadings on the spectrophotometer. This involved addingiodine, an indicator which turns blue-black in the presencesteps in theprocedure arepresentedchronologicallyof starch, to test tubes which each contained a differentconcentration of starch solution. The absorbance of eachsolution was read at 590 nm using the spectrophotometer.A series of treatments was prepared using buffers at pH5, 5.5, 6, 6.5, 7 and 8. Each test tube contained 2 ml 0.4mg ml-1 starch solution and 2 ml buffer solution. One mlamylase solution was added to each tube and the solutionsleft for 5 minutes. Four ml HCl was added to each tube tostop the reaction, after which 1 ml iodine was added.Solutionswerethenexaminedusingpast passivetensepredominates(in bold)thespectrophotometer and their absorbance measured. Theconcentrationofstarchremaining in each tube wasdetermined using the calibration curve, and rates ofreaction, at each pH, calculated. A control tube was set upfor each pH to determine if any reaction would occur withoutthe enzyme. Four replicates were used for each treatmentthroughout the experiment, to give an indication of thevariability within velinearcorrelation between starch concentration and absorbance, as statements thatlocate the ‘figures’shown in Figure 1.17
6Starch Concentration mg ml0.08-1Figure 1 Calibration curve showing the relationship between starchconcentration and absorbance at 590 nm.Rate of Reaction mmol min-1When rates of reaction were plotted against pH, a bellstatements thatpresent the most shaped curve was obtained as shown in Figure 2.important findings987654321055.566.577.58pHFigure 2 Rate of starch breakdown by the enzyme amylaseat different pH values.This indicated a peak amylase activity at pH 7 (meanstatements that-1-1comment on the rate 9.95 mmol min , range 6.8 - 13 mmol min ). Thefindingsrate of reaction declined markedly for pH values above orbelow 7 to lowest values at pH 5 (mean rate 0.9 mmol min-18
1, range 0 - 3 mmol min-1 ) and pH 8 (mean rate 3.5mmol min-1, range 1.0 - 5.6 mmol min-1 ). The controlsshowed conclusively that no reaction occurred in theabsence of amylase. Replicates revealed a large variationwithin each pH ivitywasthe mostimportant findingsmost efficiently at pH 7 and was retarded at lower or higher are summarizeddramatically affected by changes in pH. The enzyme workedpH values.Variations in replicate results were high, probably due to the limitations ofthe research arechanges in environmental conditions, variations in theindicatedequipment and its use (i.e. pipetting and spectrophotometeruse), or differences in the prior experience of researchers.The controls revealed that starch was not broken downin the time period of the experiment when the enzyme wasabsent. This would be expected given that the starch-waterreaction is exceedingly slow if amylase is not present (Purveset al., 1992). The experimental results are in agreement withstatements on enzyme action and behaviour (Purves et al.,findings arerelated to theliterature1992; Lehninger, 1975) which indicate that the enzyme’sfindings arerelated to theagreement with the original hypothesis, in that amylase original hypothesisstructure is altered at non-optimal pHs. They are also inactivity is most efficient at pH 7, which is that found in thepig’s gut.19
ReferencesLehninger, A.L. (1975). Biochemistry. Second Edition. NewYork: Worth Publishers Inc.Purves, W.K., Orians, G.H. and Heller, H.C. (1992). Life, theScience of Biology. Massachusetts: Sinauer Assoc.School of Biological Sciences. (1994). Biology 1 LaboratoryNotes, Volume 1. The University of Sydney.20
Other Types of Student WritingThe Literature ReviewThe main purpose of a literature review is to criticallyanalyse a published body of knowledge in a particular area.Depending on your assignment, the publications reviewed caninclude research articles, theoretical papers, case studies, books,other literature reviews and conference proceedings. Thesepublications are summarised, grouped or classified, comparedand evaluated.A literature review can have two forms:1.a stand-alone informative literature review paper assignedin a course, used as part of a student’s training in theresearch processes of their field; and2.a chapter in a thesis or dissertation.Depending on which form of the literature review you undertake,other purposes of the literature review can include: placing each work in the context of the subject underreview, showing how it contributes to an understandingof this subject area; describing the relationship of each work to the othersbeing reviewed; identifying inconsistencies, gaps and contradictions in thefield;21
ensuring researchers do not duplicate work that hasalready been done; pointing the way forward to further research; and placing one’s own work (in the case of theses ordissertations) in the context of existing literature.The focus and perspective of your review and the thesisor position you argue will be determined by what kind of reviewyou are writing. The stand-alone informative review synthesizesand interprets the major trends in the literature and attempts tocritically evaluate this research. The chapter in a thesis ordissertation is written to develop an argument to justify a piece ofresearch. This type of review is selective, only discussingliterature that leads to the research. One way to understand thedifferences between these two types is to read published literaturereviews (access Annual Reviews Online from the University ofGuelph Library system) or the first chapters of theses anddissertations in your own subject area.The stand-alone informative review is the type ofliterature review discussed in this section. An example followswhich illustrates some of the structural features of such a review.References in this sample are formatted according to the journal’sown style, which is a variant of CBE style. This is a guide only;please check with your instructor as to the specific requirementsof your course.Structure of the Review IntroductionIntroductions to literature reviews can vary in length fromone paragraph to several paragraphs, depending on thenature of the topic and the guidelines of the assignment.22
The average length is one to two paragraphs. Use theintroduction to fulfill the following functions. Identify your general topic, the area of concern, issue,question being addressed, establishing the context foryour review. Identify the overall trends in what has been publishedabout the topic: are there conflict
sciences. However, writing is not restricted to the arts and humanities. Language and writing are used by scientists and science students to communicate their findings and explain their research results: it is necessary to convert collected data into sent
