(Solution) SCIE1046 Activity 3.1 Bacterial Isolation

COURSE  

SCIE1046: Fundamental of Microbiology with Lab

1. About the Lab

Learning Objectives:

  • Understand the importance of bacterial growth for the investigation of pathological microorganisms.
  • Work under aseptic techniques.
  • Understand the concept of a single colony.
  • Perform plate-streaking techniques.
  • Use selective media for isolation purposes.

Estimated Length: 30 to 45 minutes

 

MAKE THE CONNECTION

The background information in section 2 was adapted from the following Microbiology lecture course Tutorials:
4.1.3 Environmental Effects on Microbial Growth
4.1.4 Media Used for Microbial Growth
4.3.5 Drug Resistance

 

2. Background Information

The following background information will be helpful as you prepare for the simulation.

Not all microorganisms cause disease. However, those that do are referred to as pathogens. There are beneficial microorganisms, including bacteria that maintain our digestive tract and those that are used to produce food, treat infections, and treat water.

Bacteria are rather small in size and must be seen with a microscope. However, bacteria grow in colonies, or groups of billions when they have a good nutrition source. When they are in colonies, they can be seen without the use of a microscope. Although a typical bacteria is small, it is about ten times larger than a virus.

Both heat and cold can be effective mechanisms to control microbial growth. Heat kills microbes by denaturing their proteins. Both refrigeration and freezing are methods used to preserve items and prevent microbial growth. This is why morgues are used to store deceased individuals and refrigeration is used to store specimens. It is important to note that cold temperatures do not kill vegetative organisms or spores, they just inhibit growth. Once conditions become ideal again, the microorganisms will begin to grow.

In nature, microbes are constantly evolving in order to overcome the antimicrobial compounds produced by other microorganisms. Human development of antimicrobial drugs and their widespread clinical use have simply provided another selective pressure that promotes further evolution. We often refer to this evolution process as microbe resistance.

2a. Prokaryote Habitats and Functions

Prokaryotes (members of domains Archaea and Bacteria) are diverse and live in varied locations including the human body, air, tap water, food, soil, fresh water, ocean water, extremely salty water, and vents at the bottom of oceans. These varied locations (the places where the organisms live) are habitats. Prokaryotes are often metabolically flexible, which means they are able to switch from one energy source or pathway to another as needed.

 

TERM TO KNOW

This glossary term is important to know and will help you during the Activity.

Habitat

The place where an organism lives.

2b. Environmental Effects on Microbial Growth

You are encouraged to review the complete Microbiology lecture course Tutorial 4.1.3 Environmental Effects on Microbial Growth for background on this topic before you begin the simulation.

2c. Media Used for Microbial Growth

You are encouraged to review the complete Microbiology lecture course Tutorial 4.1.4 Media Used for Microbial Growth for background on this topic before you begin the simulation.

2d. Drug Resistance

You are encouraged to review the complete Microbiology lecture course Tutorial 4.3.5 Drug Resistance for background on this topic before you begin the simulation.

3. Lab Manual

  Lab Manual – Bacterial Isolation

This Lab Manual gives a synopsis of the lab and the theory behind it. You’re encouraged to read or download the manual before launching the lab. This information will also be available during the simulation by selecting the “Theory” tab on the virtual LabPad.

4. Lab Report

This Activity has a Lab Report Touchstone assignment. Before launching the lab, review the Touchstone Assignment with rubric to see how you will be graded. While there, download and review the lab report file and fill it out as you complete the simulation.

IMPORTANT: You must submit the provided lab report file as your Touchstone. Any other submission file or format will be returned ungraded.

5. Launch Lab

You’re ready to begin! Review the helpful navigation tips below. Then click the “Launch Lab” button to start your lab. Be sure to answer all the questions in the simulation because they contribute to your score. Good luck, scientists!

  • Exiting:To exit a lab simulation, press the ESC key on your keyboard. This key returns you to the objective screen for the simulation.
  • Saving:You do not need to complete a simulation in one sitting. Labster saves your progress at predetermined checkpoints upon exit. To see your progress at any time, click on the “Mission” tab of the LabPad.
  • Restarting:You are allowed an unlimited number of restarts for a simulation to improve your quiz score. Sophia and Labster will always store your best score.
  • Just Browsing:You can restart a simulation to have a look around without completing it. The program will still retain your previous (and best) score.

 

HINT

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