Microbiology lab Write a lab summary about Laboratory Ex 7.1: Bacterial Metaboli
ID: 206361 • Letter: M
Question
Microbiology lab
Write a lab summary about Laboratory Ex 7.1: Bacterial Metabolism II and Identification of Unknown.The summary should be one page
Laboratory Ex 7.1: Bacterial Metabolism II and Identification of Unknown (SS2018) Objectives: After completing this lab you should understand: 1. How a variety of physical and metabolic properties of organisms are used to identify unknown organisms. 2. How to use these tests, as well as microscopy and the Gram stain, to identify an unknown bacterial strain. In this exercise, you begin the process of identifying an "unknown" organism that will be assigned to you. It will be provided as a nutrient broth culture; be sure you record the identifying number of this culture. You should first prepare smears of your unknown culture, then inoculate a new set of test media with your unknown. Remember that your unknown is one of the five organisms previously tested (as a known in 6), and that part of your grade is based on correctly identifying it. Therefore, be sure you use good aseptic technique and know how to distinguish positive and negative results for the biochemical tests. After the test media have been inoculated, perform a Gram stain on your unknown; record the Gram stain results on the lab report for Exercise 7. When you are done with your unknown culture, remove the label (put it on your lab report) and discard the culture tube in the back–DO NOT return it to the original rack–each person must have their own culture! If two students use the same culture number, they will both receive a zero for this exercise! Materials per person: 1 thioglycollate-methylene blue deep tube (THIO) 3 phenol red sugar fermentation tubes: 1@ glucose/dextrose, 1@ lactose, and 1@ sucrose 1 iron sulfate deep tube (SIM Tube) (for both H2S and Indole tests) 1 nutrient agar slant (for both catalase AND KOH tests) 1 citrate slant 1 starch agar plate 1 urea broth tube Bunsen burner Inoculating loop and needle Biochemical study guide, printed off from BB (fill in during the lab lecture) Cultures: Unknown bacterium in nutrient broth (record number). One of the five listed in Lab Six!!
Procedure: FIRST: Everyone should get an unknown culture tube, and make two slides of it. While the slides are drying, perform the rest of the lab. Remember the bacteria is already in liquid form, you do NOT need to add water to the slide! Remember this is a repeat of Lab 6. Be sure to check for any notes you made on Lab 6. A. Gram stain of your unknown 1. Perform a Gram stain of your unknown, using your previous instructions. If you wish you may ask a TA if they agree or disagree with what you think your organism is: Gram positive or negative and morphology. Remember that this does NOT mean your Gram stain is correct, since the unknowns are unknown to the TAs as well! REMEMBER: YOU ARE NOT AN EXPERT AT THE GRAM STAIN YET! DO NOT RELY 100% ON YOUR GRAM STAIN RESULTS IN DETERMINING THE IDENTIFICATION OF YOUR UNKNOWN! B. Inoculations of your unknown into the test media. 1. All inoculations will be done with your unknown and you should use good aseptic technique (including sterilizing the needle or loop between inoculations). Remember these inoculations are the same as the ones you did for your known! 2. Using your inoculating needle and good aseptic technique (including sterilizing the needle between inoculations), inoculate the thioglycolate-methylene blue deep tube (THIO), the iron sulfate deep (SIM), and the citrate slant by inserting the needle down the center of the media with your known bacterium. 3. Using your inoculating loop, inoculate the 3 phenol red sugar fermentation tubes, the urea broth tube, the nutrient agar slant (zig-zag the loop over the entire surface of the agar slants), and the citrate slant then gets inoculated a second time by running the loop (with the cloudy bacteria on it) all over the surface of the slant with your unknown. 4. Using your inoculating loop, streak your unknown in a single zig-zag line across the middle of the starch agar plate. 5. Make sure all tubes and plates are appropriately labeled, so you can find them again next week! Incubate all your test tubes in one SHORT row in the “to be incubated” racks. Place your starch plate upside down in the “to be incubated” box for your section. 6. Remove the number from your unknown culture tube and place it on Lab Report 7. Then discard your culture tube in the back in the “used test tubes” rack.
C Secure https:/cancpy.ucccubbcwebda/pid-26678162-dt content rid-66362388 1/ccursc:/2181-1.15810L20310001 552018.pd Laborutory Exercise 8: Bacterial Metabolism II and Identification of 1 15 Laboratory Ex 7.1: Bacterial Metabolism II and Identification of Unknown 552018) Objeetives: After completing this lab you should understand o variety of physical and metabolic properties of organisms are used to identify unknoan organisms. 2. How to use these tsts, as well as microscopy and th ra,toidently an unknown bacterial strain. n this exercise, you begin the process af identifying an "unknown" organism that will he assigned to you. It will be provided as a nutrient broth culture; be sure you record the idetifying number of this culture. You shoald first prepare smears of your unknown culture, then inoculate new set of test media with your unknown. Remember that your unknown is one of the five orpanisns previously testod (as a known in 6), and that part af yourgrade is based on corectly identifying it. Therefore, be sure yuu use good aseptic technique and krow how to distinguish positive and negative results for the biochemical tests Alier the test media have been inoculated performa Gram stain on our unknown; reord the Gram stain resalts on the lab report for Exerise 7 When you are done with your unknown culture, remove the lahel (put it on your lab report) and discard the culture tube in the back DO NOT return it to the original rack-cach person must have their own culture: If two students use the same culture number, they will both receive a zero for this exercise! Materials per person: 1 thioglycollate-methylene blue deep tube (THIO) 3 phenel rd sugar fementation tubes: glucosedextose, lacose, and sxcose 1 iron sulfate deep rube (SIM Tube) for both H S and Indole tests) nutrient aar slafor both catalase AND KOl tests) | cttale slant 1 starch agar plate 1 urea broth tube Bunscn buner nocularing loop and needle Bicehemical study guide, prinledol from BB (till in during the lab cture) Cultures: Unknown bacterium nutrient broth (cord number). One of the five listed in Lab Six!! Ask ma anethingExplanation / Answer
Laboratory Ex 7.1: Bacterial Metabolism II and Identification of Unknown (SS2018)
You will learn to use the properties of organisms to identify unknown organisms and how to use the Gram stain to help you with this.
First prepare smears of your unknown culture, then inoculate a new set of test media with your unknown. Remember that your unknown is one of the five organisms previously tested, perform a Gram stain on your unknown, remove the label (put it on your lab report) and discard the culture tube in the back
Materials per person: 1 thioglycollate-methylene blue deep tube (THIO) 3 phenol red sugar fermentation tubes: 1@ glucose/dextrose, 1@ lactose, and 1@ sucrose 1 iron sulfate deep tube (SIM Tube) (for both H2S and Indole tests) 1 nutrient agar slant (for both catalase AND KOH tests) 1 citrate slant 1 starch agar plate 1 urea broth tube Bunsen burner Inoculating loop and needle Biochemical study guide, printed off from BB (fill in during the lab lecture) Cultures: Unknown bacterium in nutrient broth (record number).
Procedure:
- Get an unknown culture tube, and make two slides of it.
- Gram stain your unknown, you may ask a TA if they agree or disagree with what you think DO NOT RELY 100% ON YOUR GRAM STAIN
- Inoculations of your unknown into the test media:
- Always use good aseptic technique. Inoculate the thioglycolate-methylene blue deep tube (THIO), the iron sulfate deep (SIM), and the citrate slant by inserting the needle down the center of the media with your known bacterium.
- Then using your inoculating loop, inoculate the 3 phenol red sugar fermentation tubes, the urea broth tube, the nutrient agar slant (in zig-zag), and the citrate slant then gets inoculated a second time by running the loop.
- After, streak your unknown in a single zig-zag line across the middle of the starch agar plate. Make sure all tubes and plates are appropriately labeled.
- Incubate all your test tubes in one SHORT row in the “to be incubated” racks. Place your starch plate upside down in the “to be incubated” box for your section.
- Remove the number from your unknown culture tube and place it on Lab Report
- Discard your culture tube in the back in the “used test tubes” rack.