Ubiquity of Bacteria
Microbial Diversity and Ubiquity
Microorganisms are microscopic organisms that are so small that that they can only be visualized by the aid of a compound-brightfield microscope. While we generally cannot see individual microorganisms with the naked eye, they are present in virtually every habitat known to man. Microorganisms can be prokaryotic—the bacteria or eukaryotic—the algae, protozoa or fungi. While viruses are acellular they are also studied in the scope of microbiology because they are small and because they infect cells. While most bacterial are unicellular they can also exist in colonial or multicellular forms. In this laboratory exercise you will examine the ubiquity and diversity of various microbes that are present in the environment or inhabit the human body. Most bacteria that inhabit the body are harmless or even beneficial to humans, some bacteria are opportunistic and only become pathogenic when they are present in the wrong place at the wrong time in the potential host. As microorganisms are so omnipresent, the following exercises are designed to help you learn the importance of proper asceptic technique when handling microorganisms.
During the first laboratory exercise you will be examining the examining the presence of bacteria on inanimate surfaces and on or within the human body; furthermore, you will be examining the efficacy of various cleansing agents in reducing the amounts of bacteria associated with these habitats. To this end you will first inoculate a Tryptic Soy Broth (TSB) plate with a sample from the environment. TSB is rich in nutrients and can support the growth of a number of bacteria or fungi; therefore you will be able to isolate microorganisms from your hands or other parts of the body or from the oral cavity, from your benchtop or from other inanimate objects.
With a wax pen label the bottom of a Petri plate containing TSB-agar with your name, date, lab section, and source of the inoculum. It is
Microorganisms are microscopic organisms that are so small that that they can only be visualized by the aid of a compound-brightfield microscope. While we generally cannot see individual microorganisms with the naked eye, they are present in virtually every habitat known to man. Microorganisms can be prokaryotic—the bacteria or eukaryotic—the algae, protozoa or fungi. While viruses are acellular they are also studied in the scope of microbiology because they are small and because they infect cells. While most bacterial are unicellular they can also exist in colonial or multicellular forms. In this laboratory exercise you will examine the ubiquity and diversity of various microbes that are present in the environment or inhabit the human body. Most bacteria that inhabit the body are harmless or even beneficial to humans, some bacteria are opportunistic and only become pathogenic when they are present in the wrong place at the wrong time in the potential host. As microorganisms are so omnipresent, the following exercises are designed to help you learn the importance of proper asceptic technique when handling microorganisms.
During the first laboratory exercise you will be examining the examining the presence of bacteria on inanimate surfaces and on or within the human body; furthermore, you will be examining the efficacy of various cleansing agents in reducing the amounts of bacteria associated with these habitats. To this end you will first inoculate a Tryptic Soy Broth (TSB) plate with a sample from the environment. TSB is rich in nutrients and can support the growth of a number of bacteria or fungi; therefore you will be able to isolate microorganisms from your hands or other parts of the body or from the oral cavity, from your benchtop or from other inanimate objects.
With a wax pen label the bottom of a Petri plate containing TSB-agar with your name, date, lab section, and source of the inoculum. It is