...Madeline M. Westrick Unknown 2 Unknown Lab Report INTRODUCTION In this study, each student was assigned a different unknown bacterium, with the task of identifying it correctly. Unknown 2 was Streptococcus pyogenes. S. pyogenes is gram-positive cocci that can result in human ailments that are classified as Streptococcal A infections, such as impetigo, cellulitis, erysipelas, and scarlet fever. The allotted testing time given was a total of four laboratory periods, or two weeks total. MATERIALS AND METHODS The unknown bacterial pathogen was presented via a liquid broth suspension in a double-walled glass test tube and on two nutrient agar (NA) plates. Its appearance was creamy yellow in color with sparse growth of medium-sized colonies...
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...Unknown Laboratory Report Sarah Mansfield Biology 203 Professor Lana November 19, 2014 INTRODUCTION Microorganisms are the earliest forms of life and most have thrived since the early birth of the planet. They have evolved into many different forms of life such as animals, humans, and plants. While some microorganisms impact life in a positive way by sustaining life, others cause disease and even death (Nester, et al. 2012). Prokaryotes are one of the earliest organisms to exist, and many of these organisms can thrive in conditions far worse than other living things. For example, they can tolerate extreme temperatures, acidic, or alkaline environments (Foster 1996). Prokaryotic cells do...
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...The Chapter 27 Exam will include questions from the lecture slides on the following topics. Overview: Sexual reproduction – 2 parents, union of gametes to form zygote Dimorphism – sex chromosomes, primary & secondary sex organs, secondary sex characteristic Development – gonadal ridge (becomes the gonad); mesonephric & paramesonephric ducts; fates in each sex; roles of testes determining factor (TDF), testosterone & Müllerian inhibitory factor (MIF) Gonads – descent through inguinal canal (inguinal canal); descent into scrotum (cryptorchidism) Organs & ducts: Scrotum – temperature dependence of spermatogenesis (cremaster muscle, dartos muscle, pampiniform plexus) Seminiferous tubules – germ cells, sustentacular (Sertoli) cells, interstitial (Leydig) cells Ducts – rete testis (“collecting”), epididymis (6 m long, sperm maturation), vas (ductus) deferens & terminal ampulla, ejaculatory duct, urethra Glands (general features of secretions) – seminal vesicles, bulbourethral (Cowper glands), prostate Penis – erectile tissues (corpora spongiosum, corpora cavernosa), lacunae & trabeculae [Note the fascia – this is continuous with the dartos smooth muscle layer in the scrotum.] Puberty: Stage – onset with gonadotropin rise until end of linear growth (fusion of epiphyses) Gonadotropin axis – hypothalamic GnRH, pituitary LH & FSH, sustentacular cell androgen-binding protein & inhibin, interstitial cell testosterone Testosterone...
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...Discussion: The purpose of this experiment is to identify an unknown organism over three weeks by performing lab exercises that were previously performed. The unknown #16 was chosen for this experiment. During the first week, The next step in determining this unknown was to perform the streak plate method for isolation of colonies of a 24-hour period in a 37o C incubator. The unknown organism grew on the media; observed white in color, raised with a smooth margin, shiny colonies on the TSA agar plate. The next step in identifying this unknown #16 was to steak for isolation on plated media; then incubated at 37o C for 24 hours and the stores at 4o C. The plates used for isolation were; Triple Salt Agar (TSA), Mannitol Salt Agar (MSA), Phenyl...
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...purpose of this lab was to identify one unknown Gram positive bacterium and one unknown Gram negative bacterium by observing growth patterns of differential and selective media. As shown in the results section, these tests were performed, allowing for the unknown to be determined by comparing the results of the tests with known bacteria. The Gram positive bacteria tested were Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus salivarius, Enterococcus faecalis, and unknown #2. The results of unknown #2 showed that this bacterium was non-hemolytic, catalase positive, coagulase negative, was able to grow on but not ferment mannitol salt, was sensitive to bacitracin but resistant...
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...ear Dr. Su: After your explanation of the unknowns lab report instructions, I am still left with a few questions concerning what should be the result for the lab the report. Therefore, I was hoping that you could explain to me what must be written in the report to receive a passing grade. My confusion to the assignment is in part due to the fact that my lab is inconclusive. In order to be able to classify the unknown as a certain bacteria I should be able to match its characteristics with different examples according to the different tests, but my sample matches none. I understand that in order to receive a good grade on the lab report the unknown must be correctly identified, therefore, creating more of a complication. During class you...
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...London School of Engineering and Materials Science Laboratory report writing instructions DEN101 - Fluid Mechanics 1 Flow Rate Measurement Experiment A. Student Student Number: 1234567 Version 2.0, 27 November 2010 Template for Word 97-2003 Abstract This document explains what is expected in your Fluids 1 lab report. The sections that should be covered are outlined and a structure you could follow is proposed. Detailed advice on how to edit the report is given. The document concludes with the marking criteria for this lab report. Table of Contents Abstract 2 1. Introduction 3 1.1. Writing 3 1.2. Editing and formatting 3 1.3. Content of the introduction 4 2. Background and theory 4 3. Apparatus 4 4. Test 4 5. Experimental procedure 4 6. Results 5 7. Discussion 5 8. Conclusions 5 9. References 5 10. Appendix A: Marking criteria 6 Introduction Before starting to write a report, you should think about what is your audience. Am I writing for colleagues who want a lot of detail how it is done, or am I writing for my boss who just wants an executive summary as he has no time for details? In general, there is not a single type of audience and we have to make our writing suitable for the detailed read, as well as the fast perusal. To understand what is required from you in this report, please have a look at the marking criteria in the Appendix. 1 Writing To limit...
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...For the Identification of an Unknown Compound lab, the physical properties, along with the IR and the H1 NMR will be used to determine the molecular structure and identity of the unknown compound. For the physical properties, the smell, color, state, solubility and the refractive index will be used. Then, the IR and H1 NMR be obtained using the unknown compound given during the lab. The IR and H1 NMR will play a major role in determining the molecular structure of the compound because the stretches in the IR and the peaks on the H1 NMR with indicate the functional groups present, along with indicating the number of hydrogen present in the molecular structure. Furthermore, the multiplicity in the H1 NMR will indicate where the methyl’s’, methylene’s, and methine’s are located on the structure. Overall, the unknown organic compound, NMR 180, will be identified using the observations of the physical properties and the analysis of the IR and H1 NMR obtained during the lab. Results:...
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...your unknown wisely” were the words that our instructor used when we were picking our unknown bacterial microorganism. Each person was paired with another member of the class, and was expected to work as a team to figure out the unknown that was chosen. Using steps and experiments from the Bergey’s Manual, we were suppose to figure out the unknown and how the bacteria we had chosen was classified and characterized. My hypothesis when first starting the test was that this unknown was going to be something we had already dealt with in class. I thought our unknown would be Escherichia coli. Materials and Methods When we chose our unknown bacterial microorganism, it had the number one on the side. The broth had a one in turbidity on a scale from one (being the lowest) to four (being the highest). To see more clearly in the tube, swirling was used for sediment to be seen. The first experiment we did was testing the unknown to see if it was a gram-negative bacterium or whether it was a gram-positive bacterium. Majority of the bacteria that had been handled with in class fell under gram negative. How to tell whether the bacteria is gram negative or gram positive is by staining the bacteria and watching it change it’s color. If the bacteria turn purple, that would show that the bacteria are gram-positive. If the bacteria turn red, then that would...
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...The molecular lab is a place in which students can perform techniques discussed in lecture. With these techniques one can determine a variety of things within the world of molecular. The main goal for lab this semester was to use different techniques to determine the identity of an unknown plasmid. Early in the semester each student picked an unknown plasmid. Over the course of the next few weeks, the plasmids identity was derived through the results of various techniques. The unknown plasmid selected was plasmid unknown C. Unknown C was subjected to techniques such as DNA isolation, digestions, and gel electrophoreses in order to determine the plasmids identity.The techniques were preformed and the data was collected. The data was analyzed...
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...Discussion Given the data and observation in Table 1 the identity of unknown E may be P.vulgaris because it scored a 31/38 in comparison with P.aeruginosa who had a 15/38 when both were compared to unknown E. This was based on using the Gram stain outcome and the blood agar outcomes to rule out the other species from being considered. Unknown E was a species that came from a plastic urinary catheter in a long-term healthcare facility. These conclusions are supported by literature as Enterobacteriaceae family members are mainly found in the gut flora. 6 Knowing this we can narrow the identity of the unknown to E.coli, K.pneumoniae and P.vulgaris. The result that unknown E could be P.vulgaris was observed in the beginning of the experiment, as its morphology and smell was similar. When the tests were done however, it did not match each other perfectly. This could be for multiple reasons, including the different growing conditions for unknown E and P.vulgaris, while the unknown E grew in a catheter the other was cultured in the lab. This would have had drastic implications on how unknown E would grow to behave as that colony might not be used to working in those conditions. It could have also had to do with the onsite contamination cultures...
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...Unknown compound number one is a ionic compound. For the solubility test, compound number one quickly dissolved in water. Both molecular and ionic compounds are dissolvable but ionic compounds are usually more soluble. For the conductivity test the electrical conductivity was at a rating of 5, meaning that it is a good conductor of electricity. Good conductors of electricity are usually ionic compounds. The next test was the melting point of the compound. This compound did not melt and it started burning after 30 seconds. Ionic compounds have a very high melting point like this compound does. The Last test was hardness, the hardness of unknown number one was easy to crush and it just turned into smaller, finer crystals. From these four test I conclude that unknown compound number one is ionic. Unknown compound number two is a ionic compound. For the solubility test compound number two fully dissolved in water. For the conductivity test the electrical conductivity was at a rating of 3, which could mean that this compound is polar covalent because the rating is between a poor and good electrical conductivity. The next test was the melting point of the compound. This compound did not melt...
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...HOW TO WRITE AN UNKNOWN LAB REPORT IN MICROBIOLOGY GENERAL Unknown reports in microbiology are written in scientific format. Scientific writing is written differently from other types of writing. The results of the exercise or experiment are what are being showcased, not the writing. The purpose of scientific writing is not to entertain, but to inform. The writing should be simple and easy to understand. There is a specific style that must be followed when writing scientific reports. Scientific writing is typically written in the passive voice. The pronouns "I", "We" and "They" are not typically used.. For example, instead of writing "I used a TSA agar plate to isolate my unknown," it is customary to write, "A trypticase soy agar (TSA) plate was used to isolate the unknown." It is also customary to write in the past tense for most of the report. This includes the introduction, the summary, the description of the materials and methods and the results. The present tense is reserved for the conclusions about the results. See the examples given below. Some other general rules that should be followed are: Microbial nomenclature: The name of the bacterium should written and spelled correctly. The name should be italicized or underlined. Italicized is preferred. For example, Staphylococcus aureus. The genus is capitalized but the species is not. After the full genus name is given in the paper, it can be written as S. aureus, but still italicized. This is as long as there in no other...
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...not only an academic understanding of the microscopic world but also a practical understanding of lab techniques and procedures used to identify, control, and manipulate microorganisms. The proper identification of a microorganism is not only important in a microbiology lab but also in the medical, industrial, and pharmaceutical fields. In this lab report, lab techniques and procedures learned during this course were performed to assess each students’ practical knowledge in microbiology. 6In area of fields I mention earlier microbiology is very important to our vaccination and antibiotics we are using, understand that microorganism play a key role in maintaining life on earth, fixing gases and breaking down dead plant and animal matter into simpler substances that are used at the beginning of the food chain 6. Biotechnologists can also exploit the activities of microbes to benefit humans, such as in the production of medicines, enzymes and food. The goal of this lab report is 1) to demonstrate comprehension of the methods and lab techniques learned during the semester 2) to explain the tests performed on each isolated unknown that led to the identification of each unknown 3) and to give a background on the characteristics, pathogenicity and some uses of one of the identified unknowns. II. Introduction In this lab report I will discuss how I came to find my two unknown bacteria. Each bacteria have undergo many different test to eventually identifying both bacteria....
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...IDENTIFICATION OF UNKNOWN BACTERIA It is virtually impossible to identify bacteria based on physical characteristics alone. This is due to the fact that there are only a few basic shapes and physical features commonly seen in the prokaryotic world. Instead, biochemical testing has been used to make bacterial identification down to the “species” level. These schemes are based on creating and matching biochemical profiles of the production of enzymes, acids and gases by isolated pure cultures of a given microorganism. Identification schemes and flow charts can be found in reference texts such as “Bergey’s Manual of Determinative Bacteriology” or “The Prokaryotes”. Each group of students will receive a TSA slant or broth containing a pure culture of an unknown bacterium belonging to the Family Enterobacteriaceae. It is the responsibility of the group to maintain stock cultures of the organism provided. Working stock cultures will be used to inoculate the various biochemical test media over the next several weeks and should be fresh and free from contaminants. A reserve stock culture should be made and after incubation and comparison with the original slant, kept with the original slant in the refrigerator. It is critically important that aseptic techniques are used during transfers and inoculations to prevent contamination of your cultures. If contamination is suspected, you will be able to fall back to your reserve stock. If you fail to maintain a reserve stock...
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