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1. Explain the importance of metabolic diversity to microbes and how that diversity allows different microbial species to colonize such a wide variety of habitats.
Most microbes live in communities and usually rely on metabolic interactions to increase their supply for nutrients and better exploit a given environment. Prokaryotes can be grouped into four categories according to how they obtain energy and carbon. Autotrophs are organism that can make their own food from inorganic sources. Heterotrophs are organisms that require other organisms in order to obtain organic molecules. Photoautotroph uses light as its energy source, and CO2 as its inorganic source of carbon. Photosynthetic prokaryotes, include cyanobacteria, plants, certain protists (algae). Chemoautotroph derives all of its energy from the oxidation of inorganic chemicals. They can make their organic molecules from the inorganic source such as CO2. Photoheterotroph is an organism that derives its energy from light but requires organic compounds in order to build its own organic material. Hemoheterotrophs consumes organic molecules for both energy and organic compounds. Nutritionally, chemoheterotrophs are either saprobes or parasites. Microorganisms colonize by their energy source, a food web or a food chain in ecosystem. Metabolic interactions involve the exchange of metabolic products among microbial species.
I still don't if I did answer all the question. It is hard to explain it.
3. Define and distinguish between the following key terms related to microbial control:
Sterilization – Destruction or removal of all forms of microbial life, including endospores but with the possible exception of prions. Usually done by steam under pressure such as autoclaving, boiling, or a sterilizing gas such as ethylene oxide.
Disinfection- Destruction of vegetative pathogens. May make use of physical and chemical methods such as use of phenol and phenolics, bisphenols, biguanides, halogens particularly chlorine.
Antisepsis- Destruction of vegetative pathogens on living tissue. Treatment is almost always by chemical antimicrobials such as betadine, iodine, toothpaste, mouthwash, etc.
Degerming- Removal of microbes from a limited area, such as the skin around an injection site. Mostly a mechanical removal by an alcohol-soaked swab.
Sanitization- Treatment is intended to lower microbial counts of eating and drinking utensils to safe public levels. May be done with high-temperature washing or by dipping into a chemical disinfectant. For example the use of automatic dishwasher.
Biocide- substance capable of killing microorganisms( usually with certain exceptions such as endospores). A chemical that kills microorganisms and can be synthetic or naturally occurring. A biocide can be a bactericide and/or a fungicide and/or a viricide depending on which type of microorganism(s) it acts on. An agent incorporated in or applied to surfaces of plastics to destroy bacteria, fungi, marine organisms and similar living matter. Some plastics, for example, acrylics, epoxies, phenoxies, nylons, polycarbonate, polyesters, fluorocarbons and polystyrene, are normally resistant to attack by bacteria or fungi. Others, for example, alkyds, phenolics, and urethanes can be affected by growth of these organisms on their surfaces. Even though the resins themselves might be resistant, additives such as plasticizers, stabilizers, fillers and lubricants can serve as media for fungi and bacteria. Examples of biocides are organotins, brominated salicylanilides, mercaptans, quaternary ammonium compounds, mercury compounds, and compounds of copper and arsenic.
Germicide - A germicide is any type of product that is designed to kill germs and bacteria on different types of surfaces. Many household cleaning products are formulated to function as germicides. In addition, there are some personal care products that are designed to help kill germs as part of the process of cleaning the skin. Just about any home or business will have at least a few of these products on hand at any given time. For examples are Quaternary Ammonium Compounds, Phenolics, Chlorine, Aliphatic Alcohols, Peroxides, Inorganic germicides include compounds such as sodium chlorite and potassium persulfate. Sodium chlorite has been used in water disinfection. Potassium persulfate is a new product sold as Virkon S in Europe and North America. Iodine, Aldehydes, Fumigants.
Bacteriocidal - kills bacteria by preventing essential organelles from working or proteins from functioning. Examples are Penicillins & Cephalosporins, Isoniazid, Metronidazole, Polymyxins, Rifampin, Vancomycin, Aminoglycosides, Bacitracin and Quinolones.
Bacteriostatic - prevents bacteria from growing by interfering with protein Synthesis or DNA replication. Examples are Chloramphenicol, Clindamycin, Macrolides, Sulfonamides, Tetracyclines and Timethoprim.
Asepsis- The absence of contamination by unwanted organisms. Aseptic techniques are important in surgery to minimize contamination from the instruments, operating personnel, and the patient.
Bioman,
Thank you so much for helping me.
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