Lab Report: “The Unknown” NAME: Donnise Warren PURPOSE: The purpose of this lab report is for students to be able to identify an unknown bacterium given to us by doing a variety of lab procedures and biochemical lab test to help identify what specific bacteria we have. INTRODUCTION: There are many reasons for knowing the identify of microorganisms. Such as knowing the causative agent of a disease that a patient may acquire, so that you would know how it could be treated, to knowing which microorganisms could be used for making antibiotics or even food. This lab report was done by implementing methods that have been learned throughout this semester in our microbiology lab course which helped identify my unknown bacterium #115. 6/28/2012 The 1st lab procedure performed was the gram stain.
5) Wait 24 hours. 6) Grow a bacterial culture by inoculating the bacteria from each square onto two agars. 7) Use serial dilution to get a countable plate. 8) Compare the number of bacteria on the two agar plates.
Unknown Lab Report: Enterobacter cloacae Jessica Sainvil Professor Cupido Bio 253L1 Thu 9:30-12:30 Due Date: 12/6/12 Unknown#103 Introduction The bacterium Enterobacter cloacae isolated from the given #103 was a Gram-negative Rod. The purpose of this lab was to isolate and identify the genus and species of an unknown bacterium. It is important to identify an unknown microorganism because knowing how the bacteria work and how it is structured means knowing how it can affect humans. Unknown bacteria may also be used clinically many pharmaceutical drugs are based on products made by organisms (Katzung, B.G.2004). In order to identify the unknown organism a series of tests were performed.
To get mass of food burnt, I subtracted the initial mass by the final mass. I then repeated these steps for the other two samples making sure to clean and dry the beaker each time. I got the heat energy gained by multiplying the ΔT by the mass of the water and 4.184 J/g°C. Then I calculated the heat energy per unit mass by taking my heat energy gained and dividing it by the mass of food burnt to get Joules/ g. To get the Cal of the sample I took the J/g and divided it by 4.184 and then divided that answer by 1,000 to get my Calorie. Observations: Marshmallow: I noticed that the marshmallow caught fire pretty quick.
In order to find out which antibiotics work on the bacteria, doing an agar plate test is the best way to get answers. Results; I tested the affect of a series of antibiotics on two ranges of cultures. E.Coli and S.Albus. I used four agar plates. Two for E.Coli and two for S.Albus.
September17.2013 P.4 Environmental Sources Of Bacteria Purpose: We did this lab to find out exactly which conditions would help to grow a bacterium the best. Materials: • Agar • Petri dish • Cotton • Incubator • Tape • Bacteria Procedure: 1. Mark bottom of Petri dish 2. Split petri dish into 4 sections and label the sections 3. Pour hot agar into dish 4.
The visual analysis of the results of the experiment will also be provided in which my qualitative data will be presenting which includes my own evaluation and observations of the experimental results. Quantitative & Qualitative Analysis The tables below show the results obtained by the first experiment in which I tested the effectiveness of TCP on E.coli Bacteria in 2 different petri
Once you have located these items, bring them back to the lab station and set them carefully out of the way. The other instrument needed is a Spectrovis-Plus machine, there are four located in the lab. Lab groups will rotate when they have finished the experiment. The last thing needed to perform this lab is pre filled burets, which are located on either side of the lab room. Now to begin, pour 50 mL of the sodium phosphate buffer solution with a pH of 6.84 into the 150 mL beaker.
BACKGROUND: For these experiments a 96-well plate was used. Each chemical listed would be put into their own well of 2 drops of each chemical unless instructed otherwise. After the chemicals were each dropped into the wells they were stirred with a different toothpick each time (to not cause cross contamination) and then was observed over a white piece of paper and then a black piece of paper. For each reaction I recorded the well number and took detailed notes on the reactions observed. After the first two tests done with BTB I hypothesized that acids would turn BTB yellow and that bases would remain blue.
The differential tests used to identify the unknown cultures were oxidase, catalase, lactose and sucrose fermentation, nitrate reduction, gelatin hydrolysis, starch hydrolysis, manitol salt, MR-VP, citrate, indole, urease, DNase, and coagulase. The tests performed on the unknown bacteria cultures were all used to determine the identity of the bacteria. Each of the tests performed provided some key information about the bacteria in question and how it functions. All of the tests were performed on every culture, however, as some of the tests were used only for gram (+) or gram (-) bacteria, while others were even more specific and identified only for cocci bacteria. The tests performed and what constitutes a positive and negative test are as follows.