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42: Unknown Bacteria Identification Project Report

  • Page ID
    90588
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    Learning Objectives
    • Write an organized and well formatted scientific report detailing the Unknown Identification Project.
    • Understand expectations of the Unknown Identification Project Report and grading guidelines.

     

    Instructions for Writing Unknown Bacterial Species Identification Project Report

     

    Originality

     

    TurnItIn

    The words in your report must be 100% your own. To make sure that the report is 100% your own, you will submit this report using TurnItIn. TurnItIn compares your report with websites, books, publications, and the work of other students who have submitted their documents to TurnItIn. For your report to be acceptable, the similarity rating between your work and other works will need to be below 20%.

     

    Citing Sources

    You may use outside resources to provide information that will help you to write the report (e.g. information about Gram stains, oxidase test, starch hydrolysis test, etc.), but you must cite the sources of information you used. The text must also be fully in your own words. Do not just change a couple words around. TurnItIn is smarter than this and will flag the text.

     

    Example 42.1

    Example of scientific writing using information from an external source:

    The initial Gram stain was unsuccessful the first time since all of the cells appeared purple, indicating that the decolorization step was too short (Pakpour and Horgan, 2021). As a result, the initial Gram stain was repeated using a decolorization step that was 10 seconds longer than in the previous attempt. This produced a Gram stain where Gram negative rods and Gram positive cocci were apparent.  

    More Information about this Example

    In this example, the authors' last names are Pakpour and Horgan and the work is from 2021. A full reference would then be provided at the end of the report in a "Works Cited" section.

     

    Works Cited Section

    A works cited section is found at the end of a scientific report. It lists the full references for all external resources cited throughout the entire report. There are many different ways to format a Works Cited section. What matters most is:

    • you use the same professional formatting for your references (i.e. consistency) 
    • references are complete (with title, year, author name(s), publisher/journal/book name, URL (if applicable), page numbers/name (if applicable), etc.)
    • references are listed in alphabetical order

     

    Example 42.2

    Works Cited

    Hartline, 2022. Starch Hydrolysis. Microbiology Laboratory Manual. LibreText. Accessed on 10/30/2022 from: 

    https://bio.libretexts.org/Courses/West_Hills_College_-_Lemoore/Microbiology_Laboratory_Manual/17%3A_Starch_Hydrolysis 

     

    Pakpour and Horgan, 2021. Lab 3: Simple, Negative, and Gram Stain. General Microbiology Lab Manual (Pakpour & Horgan). LibreText. Accessed on

    10/29/2022 from: https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/Microbiology_Labs/Book%3A_General_Microbiology_Lab_ Manual_(Pakpour_and_Horgan)/Lab_03%3A_Simple_Negative_and_Gram_Stain

     

    Quoting Sources

    Quoting another author in the sciences is rare. As a result, in this report, quoting another author is not allowed. Take information from texts and put it into your own words and cite the source. Don't just change one or two words (Turn It In will flag this). You need to write your own sentence using the ideas you read. Or even better, synthesize your own ideas and results together with ideas from another source and then cite the source.

    This type of synthesis is shown in the example above discussing the Gram stain. Events and results from the laboratory were synthesized together into the same sentence with the idea in the cited source that the decolorization step was too short since all the cells appeared purple.

     

    Working with Your Partner

    Since you and your partner worked together and will have done the same steps and will have the same results, it may be tempting to share parts of your reports with each other. TurnItIn will recognize the similarities between your reports and flag it as plagiarism.

    You must write your own report without sharing text with your partner. However, you are encouraged to get your partner to proofread your report and give feedback and comments to help improve the report before you submit it. The images in your reports may be the same since you will share the same results and will want to choose the best photos for the report.

     

    Organization of the Report

    The report should be broken into the following sections. Each section should have a bold header with larger font that the text in each section. Do you see how this document is separated into sections with bold headers? This is how your report should look too, except name each section as follows:

    • Introduction
    • Methods
    • Results & Discussion
    • Works Cited
    • Activity Log

     

    Example 42.3
    Introduction

    Introduction text / subsections here.

    Methods

    Methods subsections and text here.

    Results & Discussion

    Results and discussion subsections and text here.

    Works Cited

    Full references here in alphabetical order.

    Activity Log

    Photos of activity log pages here.

     

    Introduction

    An introduction gives important background information to the reader. Don't write this report assuming that your instructor knows all of this information already and therefore you shouldn't include it. Instead, write the report as if you were writing it for a biology student who hasn't taken microbiology yet. Therefore, you will need to:

    • Address the reasons why identifying bacterial species is important.
    • Describe how (generally speaking) identifying bacterial species is done.
    • Describe each of the microbiological tests and microbiological approaches that you used in this project including:
      • how each works
      • what each test tells about the bacteria
      • how you determine the results of a test

     

    Example 42.4

    For example, if you identified your bacteria as Bacillus subtilis and Escherichia coli, you will have different paragraphs or sub-sections in the Introduction on the following topics:

    • Streak plate
    • Gram stain
    • Starch hydrolysis
    • H2S production
    • Oxidase test
    • Lactose fermentation

     

    In the paragraph introducing the Gram stain (for example), you will need to discuss:

    • How the crystal violet stain will remain inside a thick layer of peptidoglycan
    • How the crystal violet stain will be decolorized from a thin layer of peptidoglycan
    • How cells with the thin peptidoglycan layer are stained with a different color
    • The structure of the cell walls of Gram-positive bacteria
    • The structure of the cell walls of Gram-negative bacteria
    • The color Gram positive bacteria appear in the microscope after the Gram stain
    • The color Gram negative bacteria appear in the microscope after the Gram stain

     

    Important

    End the introduction with a paragraph that describes the basic premise and approach of this project and how this approach either resulted in the successful identification of both unknown bacteria, one identification was successful and the other unsuccessful, or that both were not correctly identified. Be sure to name the species you had and what species you identified them as.

    It may seem like this is spoiling the ending of the paper - and it is! This is common among scientific publications to end the Introduction with a paragraph that tells the reader what they can expect to read about in the rest of it.

     

     

    Methods

    Methods will tell the approaches you used to conduct each test. The Methods section does not discuss the concepts of each test, the meaning of each test, or the results of the tests. The Methods section describes what you did with your bacteria in the laboratory for each test and how you did the tests. The Methods is written in paragraph form (do no bulletpoint or number steps - do not copy from laboratory protocals). Separate the Methods section into subsections.

     

    Example 42.5

    Continuing the example from above where you identified your bacteria as Bacillus subtilis and Escherichia coli...

    Methods
    Streak Plate

    Text here about what you did to make your streak plates (e.g. using aseptic technique, using a Bunsen burner and loop, where bacteria were collected from [e.g. original Unknown culture, stock TSA slant, etc.], how the petri plate was streaked in quadrants while flaming loop in between, plate inverted and incubated at 37°C for 48 hours).

    Gram Stain

    Text here about what you did to make bacterial smears and conduct Gram stains.

    Starch Hydrolysis Test

    Text here about what you did to do the starch hydrolysis test.

    H2S Production Test

    Text here about what you did to do the H2S production test.

    Oxidase Test

    Text here about what you did to do the oxidase test.

    Lactose Fermentation Test

    Text here about what you did to do the lactose fermentation test.

     

    Since you are only describing how you did a test (the steps you took in the laboratory to do the tests), each subsection in the Methds may be relatively short. The Methods section should not include any results and is not the place to discuss the theory of each test. It should simply state how each test/component was done.

     

    Example 42.6
    Methods

     

    H2S Production

    To test whether Unknown Bacteria A produces H2S, Unknown Bacteria A was aseptically transferred from the stock TSA slant into a SIM deep using an inoculation needle. This culture was incubated at 37 °C for 48 hours before it was examined to determine test results.

     

     

    Results & Discussion

    Separate the Results & Discussion section into subsections.

     

    Example 42.7

    Continuing the example from above where you identified your bacteria as Bacillus subtilis and Escherichia coli...

    Results & Discussion
    Streak Plate

    Text here about streak plate results and discussion

    Gram Stain

    Text here about Gram stain results and discussion

    Starch Hydrolysis Test

    Text here about starch hydrolysis results and discussion

    H2S Production Test

    Text here about H2S production test results and discussion

    Oxidase Test

    Text here about oxidase test results and discussion

    Lactose Fermentation Test

    Text here about lactose fermentation test results and discussion

    Project Conclusions

    Text here discussing the conclusions of the project.

     

    Important

    Each Results & Discussion subsection should contain both results and discussion:

    • Results: simply tells the observation(s) from each test. 
    • Discussion: interprets observations and the meanings of the results of each test.

     

    Example 42.8

    Result for Gram stain Section: "The initial Gram stain showed a mixture of purple-colored cocci arranged in chains and pink-colored bacilli."

    Discussion for Gram stain Section: "These results indicate that Unknown Culture #4 contains Gram-positive cocci, possibly Streptococci, and Gram-negative rods. The bacteria staining Gram-positive have a thick layer of peptidoglycan in their cell walls and lack an outer membrane. The Gram-negative bacterial species have cell walls with a thin layer of peptidoglycan and an outer membrane."

     

    The Results and the Discussion should be synthesized together in paragraph form in each section.

     

    Example 42.9

    Example of a Gram Stain subsection of the Results & Discussion:

    "The initial Gram stain showed a mixture of purple-colored cocci arranged in chains and pink colored rods. This indicates that Unknown Culture #4 contains Gram-positive cocci, likely Streptococci, and Gram-negative rods. The bacteria staining Gram-positive have a thick layer of peptidoglycan in their cell walls and lack an outer membrane. The Gram-negative bacterial species have cell walls with a thin layer of peptidoglycan and an outer membrane.

    "After these bacteria were isolated using the quadrant streak-plate technique, the subsequent Gram stains showed one isolate appeared as purple cocci and the other isolate were pink bacilli. There was no evidence of pink bacilli with the purple cocci or purple cocci with the pink rods. This indicates that the two species that were examined in the initial Gram stain were successfully isolated and separated into their own cultures. The purple-staining cocci are a Gram positive bacterial species and will hereafter be referred to as "Unknown Bacteria A." The pink-staining rods are a Gram negative bacterial species and designated as "Unknown Bacteria B" in the remainder of this report."

     

    In the example text above, the description would be further supported with images of the initial Gram stain, the Gram stain of Unknown Bacteria A, and the Gram stain of Unknown Bacteria B. These images will require captions to indicate what the image is. Images can be placed as separate figures, each with their own caption, or arranged together as a single figure with a single caption.

     

    Example 42.10

    This is an example of a single photo showing results with its caption:

    Gram-positive-cocci-and-Gram-negative-bacilli (1).jpg

    Figure 1: Results from initial Gram stain of the original Unknown Bacterial Culture showing both species mixed together in this culture.

     

     

    Example 42.11

    This is an example of multiple photos that have been put together as a single figure with one caption:

     

    Gram stain composite figure

    Figure 1: (A) Results from initial Gram stain of the original Unknown Bacterial Culture showing both species mixed together in this culture. (B) Gram stain of isolated unknown bacteria "A." (C) Gram stain of isolated unknown bacteria "B."

     

    Important

    In the Project Conclusions subsection of the Results & Discussion section, include the following:

    • Name the two bacterial species that you determined in your tests were the species in the unknown culture.
    • Give a very brief (1-2 sentences) summary of how you came to the conclusions of the species you identified.
    • Tell if the bacterial species identified were in fact the species that you had in the unknown culture.
    • If there was a misidentification, tell what species you did have and reflect on and discuss sources of error or events during the project that might have led to misidentification.
    • If you successfully identified the bacterial species, reflect on and discuss what likely contributed to your successful identification of the bacterial species.

     

     

    Activity Log

    Take clear photos of the activity log or scan these pages and include them in this section of the report.

     

    Writing Style

     

    Write in Third Person

    Write in the third person. This means that you act as a narrator as if you were outside of the experiment and not involved in the experiment.

    • First person (don't write this way): I examined my Gram stain and saw that the cells were pink.
    • First person (don't write this way): We examined our Gram stain and saw that the cells were pink.
    • Second person (don't write this way): When you examined the Gram stain, you saw that the cells were pink.
    • Third person (write this way): Upon examining the Gram stain, pink cells were observed.

     

    Write in Past Tense

    Write in the past tense.

    • Future tense (don't write this way): A Gram stain will be done.
    • Present tense (don't write this way): A Gram stain is being done.
    • Past tense (write this way): A Gram stain was done.

     

    Proofread

     

    Use Grammar and Spelling Checkers

    Check all of your text for proper grammar and spelling. Make adjustments were necessary.

     

    Write Early & Read Multiple Times Before Submitting

    Complete your report at least a few days before submitting it. Read it a couple times after writing it (including on separate days). Make edits on each reading.

     

    Have a Classmate Proofread and Give Feedback

    Complete your report early, print out a copy or email it to a classmate and ask them to read it over and make notes to help you to improve your report. Make edits that you deem will improve your report as suggested by your classmate.

     

     

    Instructions for Submitting the Report

    Upload a file with your Unknown Identification Project Report in the PROJECT: Unknown Identification Project Report assignment in Canvas. This upload will use TurnItIn.

     

    TurnItIn will:

    • Electronically analyze and review the text in your document to insure your work is original.
    • Compare your work to its student paper repository.
    • Compare your work to current and archived web site content.
    • Compare your work to periodicals, journals, and publications.
    • Create an originality report of your work.
    • Both you and your instructor will be able to see the originality report.

     

    See how to upload your work to this assignment in this video guide:

     

     

    Grading

     

    Low Participation Activity Log Deductions

    • Reports with activity logs that show 20% less work than your partner will receive a 10% deduction.
    • Reports with activity logs that show 40% less work than your partner will receive a 20% deduction.
    • Reports with activity logs that show 50%-70% less work than your partner will receive a 50% deduction. 
    • Reports with activity logs that show 75%-100% less work than your partner will receive an 80% deduction.

     

    Grading Rubric

     

     

    five stars

    Five Stars (100%)

    four stars

    Four Stars   (85%)

    three stars

    Three Stars (70%)

    two stars

    Two Stars (50%)

    One star

    One Star (20%)

    zero stars

    Zero Stars (0%)

    Introduction

    (40%)

    The Introduction section thoroughly and accurately addresses all expected components for the introduction. Excellent writing quality and style. Citations are included as appropriate.

    The Introduction section addresses most of the expected components and most or all of the components are accurate. Writing style demonstrates quality and thoughtful development. Citations are included as appropriate.

    The Introduction section addresses some of the expected components and most/some of the components are accurate. Writing and writing style may be good or may requires some improvement. Citations may or may not be included.

    The Introduction section addresses a few of the expected components and some of the components are accurate. Writing and writing style requires additional development. Citations may or may not be included.

    The Introduction section only slightly addresses the expected components.  Writing and writing style requires additional development. Citations may or may not be included.

    The Introduction section is absent or addresses almost none of the expected components. Writing and writing style requires a lot more development. Citations may or may not be included.

    Methods

    (10%)

    The Methods section thoroughly and accurately addresses all expected components without including text better suited to the introduction or results & discussion sections. Excellent writing quality and style.

    The Methods section addresses most of the expected components and most or all of the components are accurate without including text better suited to the introduction or results & discussion sections. Writing style demonstrates quality and thoughtful development.

    The Methods section addresses some of the expected components and most/some of the components are accurate and may include text that would be better suited to the introduction or results & discussion sections. Writing and writing style requires additional development.

    The Methods section addresses a few of the expected components and some of the components are accurate and may include text that would be better suited to the introduction or results & discussion sections. Writing and writing style requires additional development.

    The Methods section addresses a few of the expected components and some of the components are accurate and may include text that would be better suited to the introduction or results & discussion sections. Writing and writing style requires additional development.

    The Methods section is absent or addresses almost none of the expected components and may include text that would be better suited to the introduction or results & discussion sections. Writing and writing style requires a lot more development.

    Results and Discussion

    (45%)

    The Results and Discussion section thoroughly and accurately addresses all expected components. Quality figures are provided to support results and have captions. Excellent writing quality and style. Citations are included as appropriate. Report conclusions are reflective and complete.

    The Results and Discussion section addresses most of the expected components and most or all of the components are accurate. Figures are provided to support results and may or may not have captions. Writing style demonstrates quality and thoughtful development. Citations are included as appropriate. Report conclusions are reflective and complete.

    The Results and Discussion section addresses some of the expected components and most/some of the components are accurate. Figures are provided to support results and may or may not have captions. Writing and writing style requires additional development. Citations may or may not be included. Report conclusions are included, but may be incomplete, lack thought/ development.

    The Results and Discussion section addresses a few of the expected components and some of the components are accurate. Figures may or may not be provided to support results and may or may not have captions. Writing and writing style requires additional development. Report conclusions may or may not be included and may be incomplete, lack thought/ development.

    The Results and Discussion section does not address most of the expected components. Figures may or may not be provided to support results and may or may not have captions. Writing and writing style requires additional development. Report conclusions may or may not be included and may be incomplete, lack thought/ development.

    The Results and Discussion section is absent or addresses almost none of the expected components. Writing and writing style requires a lot more development. Citations may or may not be included. Report conclusions may or may not be included and may be incomplete, lack thought/ development.

    Works Cited

    (5%)

    The Works Cited section has consistent formatting for all references. References are provided for each citation in the text. Information included is thorough. References are listed in alphabetical order.

    The Works Cited section has consistent formatting for all references. References are provided for each citation in the text. Information included is mostly thorough, but some important information is missing. References are listed in alphabetical order.

    The Works Cited section has mostly consistent formatting for all references. References are provided for most of the citations in the text. Information included is mostly thorough, but some important information is missing. References order may or may not be alphabetical.

    The Works Cited section has inconsistent formatting. References are provided for most/some of the citations in the text. Information included is missing components. References order may or may not be alphabetical.

    The Works Cited section lacks formatting. References are missing or most of the information required for full references are missing. References order may or may not be alphabetical.

    Works Cited section is either missing or is just a list of titles or websites used without any attempt at formatting or organization.

     

     

    Attribution


    This page titled 42: Unknown Bacteria Identification Project Report is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Rosanna Hartline.

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