BIOS 242 Week 3 Lobster OL Bacterial Isolation

Name

Chamberlain University

BIOS-242 Fundamentals of Microbiology

Prof. Name

Date

Learning Objectives

The primary learning objectives of this lab include understanding the importance of bacterial growth when investigating pathological microorganisms. Participants will also learn to apply aseptic techniques to maintain sterile laboratory conditions. Additionally, the lab will guide learners in defining the concept of a single bacterial colony, performing the plate streaking technique for bacterial isolation, and utilizing selective media to aid in the isolation process.

Introduction

Welcome to the Bacterial Isolation virtual simulation lab. The focus of this lab is to explore the contamination of poultry meat by an antibiotic-resistant bacterial strain. The objective is to collect samples of this deadly bacteria from various species. This simulation requires practicing sterile techniques, especially the plate streaking technique, to ensure proper bacterial isolation.

Identifying Ampicillin-Resistant Bacteria

In this lab, you will identify strains of bacteria resistant to ampicillin found in poultry meat. The main task is to collect samples that contain multiple bacterial strains and isolate the ones that are ampicillin-resistant by obtaining single colonies. This allows for further analysis of these strains.

Aseptic Technique

Throughout the simulation, you will be practicing aseptic techniques. These techniques are essential in microbiology to maintain a sterile environment and prevent contamination. The process involves turning on a Bunsen burner and sterilizing your inoculating loop between streaks.

Plate Streaking Technique

A critical part of the lab is the plate streaking technique, used for bacterial isolation. Unlimited agar plates are provided for practicing this technique repeatedly. Immediate results are available, unlike in real-life situations where incubation may take up to 24 hours. Additionally, you will streak a specialized Salmonella Shigella agar to promote the growth of Gram-negative strains. Each strain will exhibit a distinct phenotype on this medium, assisting in the identification of ampicillin-resistant bacteria.

Questions

1. Purpose:

The purpose of this experiment is to gain practical experience in culturing and isolating bacteria. We performed the plate streaking technique to separate and test different bacterial strains, helping us understand the significance of bacterial isolation in microbiological research.

2. Why is proper aseptic technique important in microbiology?

Proper aseptic technique is vital in microbiology to prevent contamination and ensure the integrity of the experiment. It stops unwanted microorganisms from interfering with the cultured bacteria and ensures reliable and accurate results.

3. Why is flaming the inoculating loop or needle before and after each injection important?

Flaming the inoculating loop or needle sterilizes the instrument, removing any bacteria present. It also prevents cross-contamination between different samples, ensuring the purity of the tested cultures. Additionally, waiting for the loop to cool after flame sterilization is crucial to avoid damaging the bacterial culture.

BIOS 242 Week 3 Lobster OL Bacterial Isolation

4. Why is it essential to flame the neck of the tubes immediately after uncapping and before recapping?

Flaming the neck of the tubes is essential to maintain sterility. It prevents any environmental bacteria from contaminating the sample and ensures the integrity of the culture. This step creates a sterile barrier that protects the culture from contamination.

Reflection

During this simulation, I learned about the risks associated with antibiotic-resistant bacteria, particularly in poultry. It emphasized the importance of proper cooking to avoid infections. Additionally, I gained practical knowledge in bacterial isolation and the plate streaking technique, which deepened my understanding of microbiological procedures. I appreciated the opportunity to repeat the experiment, especially when I made mistakes, which helped improve my techniques. However, the occasional freezing of the simulation was frustrating as it interrupted the workflow and extended the time required to complete the assignment.

References

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.).