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WGU D311: Task 2 Unknown Lab Manual for Microbiology with
Lab|2025 Update with complete solution
Task 2: Unknown Lab Manual 1
The goal in this Task 2 lab is to identify an unknown that learners might encounter in the real world using the least number of instruments and tools as possible while still replicating the problem-solving purpose of the lab experience. Learners will be provided with lab evidence and will need to determine the next test steps until a final identification is confirmed. This lab will encourage critical thinking, analysis, reasoning, and decision-making that forges connections among complex systems while solving a problem.
Task Instructions:
Welcome to Unknown 1 Lab! Your goal in this lab is to use various laboratory tests to identify an unknown organism. Before proceeding, double check that you have selected the correct group based on the first initial of your last/family name.In a laboratory setting, your time and resources are limited. While the results of several tests are provided in this manual, remember that you will not use every test to make an identification.Instead, use the provided decision tree to choose each next step, narrow down your choices, and identify your unknown organism.In your lab report, you will only be discussing the Gram stain and two additional tests that you selected based on the decision tree and your results. You will be asked to explain your reasoning for each test that you select. Once you have identified your unknown organism, you will use the results of the Kirby-Bauer diffusion test to select an antibiotic for treatment.
Investigation Tools:
Refer to Section 4, Lesson 2 to review the information about Gram staining and to reference the decision tree. As a reminder, the decision tree will guide you in making decisions about which tests to explore along the journey to identify your unknown organism. Save your lab report as a Word document, titled D311 Task 2 Lab Report Last Name. Important Step: In your lab report, indicate which unknown organism number you will identify, or your work will be returned to you without evaluation.
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Lab Directions:
- Identification of your unknown bacterial specimen will begin with the Gram stain.
- Observe the Gram stain results.
Gram Stain Results
- Guided questions: The following questions will help you formulate and complete your lab
report. It is important to document your answers to reference when you write the lab report. Is this organism Gram-positive or Gram-negative? Why did you make this decision? What evidence supports your reasoning? Is this organism's morphology bacillus- or coccus-shaped? What evidence supports your reasoning?
4. Next Step: Next Test
In a laboratory setting, you would not be able to run all available tests on every organism. Your choice for the next test to perform should be intentional, based on the previous test results, and guided by the provided decision tree. You will be asked to explain your reasoning for selecting each test as part of your lab report.
Select the next test:
Endospore stain (p3) Catalase test (p10) Glucose fermentation test (p8) Citrate test (p6) Blood agar growth/ hemolysis(p5) Back to Gram stain results (p2) Capsule stain (p4) Motility test (p12) Lactose fermentation test (p9) Voges- Proskauer test (p7) Coagulase test (p11) Kirby-Bauer results (p13)
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