Aseptic Technique 2
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Biological Concepts
Microorganisms and Biotechnology
Use of Aseptic Technique
Introduction
Microorganisms (microbes) such as prokaryotes are the oldest life form that we know. Various forms have been discovered, not only to survive, but to thrive in the most hostile and extreme of environments and have been named extremophiles and various types of microbes are found in every niche of ecology. Due to their resilience and success at sustaining their existence, it has proven to be quite difficult to control their reproduction where they are harmful. (Toole & Toole, 1995).
Some types are symbiotic and are crucial to the survival of other organisms e.g. the dinoflagellates found living amongst the polyps of reef-inhabiting coral. (Dorit, Walker & Barnes, 1991). Others exist in their own right, but are harmless and many are useful e.g. yeast, used in the production of beer and baking or enzymes used in the food industry, which are produced from microorganisms. Pathogens however can cause damage or even bring about death to other organisms and these are the microbes that humans have battled to control over many years with varying degrees of success. (Toole & Toole, 1995)
Microscopic parasites such as Nematodes (roundworms) are diverse. Treatments for such infestations target inhibition of growth or reproduction.
If an area needs to be treated to prevent the infection of another organism disinfectants may be used. They work by inhibiting the growth or destroying the microbes whilst in their vegetative state. Some disinfectants (e.g. alcohols) disrupt the integrity of the lipid content within the membranes of the cells. This eventually leads to the rupture of the cell. Disinfectants that are halogen based (e.g. chlorine) denature the proteins in the cells, thereby killing the microbes. (Toole & Toole, 1995).
Viruses, unlike bacteria, are obligate intracellular parasites that can only reproduce after infecting host cells.
Biological Concepts
Microorganisms and Biotechnology
Use of Aseptic Technique
Introduction
Microorganisms (microbes) such as prokaryotes are the oldest life form that we know. Various forms have been discovered, not only to survive, but to thrive in the most hostile and extreme of environments and have been named extremophiles and various types of microbes are found in every niche of ecology. Due to their resilience and success at sustaining their existence, it has proven to be quite difficult to control their reproduction where they are harmful. (Toole & Toole, 1995).
Some types are symbiotic and are crucial to the survival of other organisms e.g. the dinoflagellates found living amongst the polyps of reef-inhabiting coral. (Dorit, Walker & Barnes, 1991). Others exist in their own right, but are harmless and many are useful e.g. yeast, used in the production of beer and baking or enzymes used in the food industry, which are produced from microorganisms. Pathogens however can cause damage or even bring about death to other organisms and these are the microbes that humans have battled to control over many years with varying degrees of success. (Toole & Toole, 1995)
Microscopic parasites such as Nematodes (roundworms) are diverse. Treatments for such infestations target inhibition of growth or reproduction.
If an area needs to be treated to prevent the infection of another organism disinfectants may be used. They work by inhibiting the growth or destroying the microbes whilst in their vegetative state. Some disinfectants (e.g. alcohols) disrupt the integrity of the lipid content within the membranes of the cells. This eventually leads to the rupture of the cell. Disinfectants that are halogen based (e.g. chlorine) denature the proteins in the cells, thereby killing the microbes. (Toole & Toole, 1995).
Viruses, unlike bacteria, are obligate intracellular parasites that can only reproduce after infecting host cells.